Ee2
Mesograzers
, by feeding on these epiphytes andalgae may be able to buffer some of these negative effects of eutrophication on seagrass As you can see in these figures, when deterrent was added, the amount of grazers decreased , and this wasparticularly true for amphipods , also partly for isopods , whereas gastropods were not affected by the deterrentAnd this removal of grazers translated into an increase in epiphytes and decrease of seagrass when nutrients wereadded. On the other hand, when mesograzers were present, the increase in nutrients did not have negative effectson seagrass, because grazers were able to control the overgrowth of epiphytes .3 General idea- when nutrients are added tothe system algal biomass increasesAnd, that grazers can reduce the amount of these epiphytes. Interestingly, though, they found that the decrease inepiphyte biomass was much more correlated with the diversity of mesograzers (i.e. the number of different speciesof mesograzers that were present), rather than with the total abundance of mesograzers.5 Diversity of grazers is positively correlated with diversity of seagrass even more so with plant diversity promoting higher diversity of planmt gentic diversity promotoes higher diversity of the mesogazer community- positive feedback for resiting eutrophication Relationship of bottom-up and top-down control
Describe the four main challenges to estimating fishing mortality in estuaries.
. Estuaries do not encompass the complete life cycle of many species that inhabit them. b. Most fisheries statistics collection programs do not distinguish between fish of the same species caught in estuaries versus the nearby coastal ocean. c. Estuarine fisheries are typically small-scale in nature making the routine collection of CPUE data too costly. d. Most stock assessment methods require the costly collection of age data for fish caught.
At a very high trophic transfer efficiency of 20% it takes
16,000 units of primary production to support CLICK - 1 unit of production at trophic level 7 (note that the book says this is trophic level 6, but I think the authors got the calculation wrong - sorry for the confusion) At the typical trophic transfer efficiency of 10% so much material and energy is dissipated that CLICK - 16000 units of primary productionCLICK - only supports 1.6 units of production at trophic level 5. But of course no natural food webs are truly linear in this way, and many organisms shortcut the food web by feeding at multiple trophic levels, which reduces their average trophic level. CLICK - Filter feeders in estuaries are a perfect example of this - like menhaden and sardines and oysters and mussels. These organisms are able to feed on very small organisms at very low trophic levels. And that makes them efficient producers and they support strong, stable fisheries like the menhaden fishery on the gulf coast
Oyster bed
1705 dublic bat
Increase atm co2 and ocean co2
30% of the co2 has been release in the atmosphere has been abosphered by ocean c02 reacts with water creating carbobic acid- weak acid, but the protons cause ph water changes more protons - lower ph lower the ph- mor acid, OCEAN ACIDIFICATION a small change in ph can mean a doubling of the amount of hydrogen ion, 15 to 10 .3 point change actually means doubling the concen of protons increase in c02 causes a decrease in conc of carbonate ions
How do direct trophic interactions differe from indirect trophic interactions? give an example of each that you might find in an estuarine food web
A direct trophic interaction between organism pairs or groups of organisms must first be a trophic interaction (i.e., defined by a feeding relationship) and second be a direct interaction, meaning that one group involved in the interaction must directly feed on the other. The relationship between a grazer on phytoplankton and the phytoplankton it consumes is a direct trophic interaction in which the grazer has a negative effect on phytoplankton, and the phytoplankton has a positive effect on the grazer. An indirect trophic interaction is also a trophic interaction, but in this case the feeding by one group on a second group impacts the abundance of a third group. One example is a trophic cascade where a predator feeding on a grazer may have an indirect positive effect on a primary producer, whose biomass may increase when grazing declines due to mortality of grazers caused by the predator.
Esuaries often contain a wide variety of habitat types Discuss some of the consequences of this spatial variability on estuarine food webs
A diversity of habitat types in estuaries can help maintain diversity and stabilize trophic interactions. Trophic interactions can cause large variations in population size and potentially competitive exclusion. For example, a very successful predator could have a strong negative effect on the abundance of its prey. However, the spatial mosaic of habitats in estuaries can stabilize estuarine food webs by providing refuge from predation. Estuarine habitats also may be defined by variations by physical water quality variables such as water temperature, salinity, or dissolved oxygen. Some estuarine species can change their location or depth to use habitats with water quality conditions that their predators or competitors avoid, thereby changing the trophic interactions.
How do flow cycles differ from flow pathways in a food web
A flow pathway or trophic pathway in a food web is a linear sequence of trophic steps from any node in a food web to any other connected node. A flow cycle is a trophic pathway that returns to a node from which it originated, resulting in recycling of matter or energy within the food web. Most flow cycles flow through detritus because trophic pathways through living organisms generally lead to progressively larger organisms.
What is meant by a static food web model? What is an alternative to analyzing a static model and how does it differ?
A static food web model is a representation of the trophic flows in a food web at a particular point in time. A static model can be analyzed to reveal food web structure and other characteristics of the food web (e.g., size or total system throughput, number of trophic levels, importance of cycling). A dynamic food web model describes interactions among organisms in a food web over time and may describe or predict changes in the abundance or biomass of organisms at different nodes of the food web. A dynamic food web model requires additional information about trophic relationships and population dynamics that is not needed to create a static food web model.
What is a trophic guild? Describe several key trophic guids that occur in estuarine food webs
A trophic guild describes a group of organisms who feed in a similar way, either on similar prey (e.g., plankton) or by a similar mechanism (e.g., suspension feeding). A trophic guild can be defined very narrowly (i.e., very specific diet, or very specific feeding mechanism) or alternatively can be defined more broadly. Some very commonly described trophic guilds based on feeding mechanism include suspension feeders, which obtain food by removing small particles from the water and deposit feeders, which ingest sediments and extract nutrition from the organic components present, while egesting mineral sediment and other unusable parts of the sediment. Guilds defined in terms of food type can include planktivores (consumers of plankton), piscivores (consumers of fish) and benthivores (consumers of benthic animals).
For parts of the world, including the Pacific Coast of the US, salmon are an iconic, estuarine-dependent species. How is their future survival threatened by global climate change? (Select all that apply)
A warming climate may increase winter flooding. A warming climate may result in higher stream temperatures. Yes, higher stream temperatures may present a thermal barrier to spawning and migration. Correct Answer A warming climate would reduce spring snowpack. Correct! Rates of ESLR will increase under a regime of global warming Yes, rapid rates of ESLR could result in the loss of crucial estuarine habitat.
Open water changes in metabolites
Advantages• Integrates all P and R (water, sediment, grasses, etc.)• Easy - can do long term observation• Disadvantages• Gas exchange!!! - requires an atmospheric exchange correction• Horizontal advection (problem in estuaries) The advantages of this method is that it is highly integrative, and captures the contributions of water, sediment, grasses, everything. Plus it is rather easy to do.CLICK - The disadvantages are mostly that gas exchanges with the atmosphere. So as oxygen increases during the day you have to account for the fact that some of it is blowing off into the atmosphere, and the rate of that exchange depends on temperature, wind, waves, and several other things. This is complicated and requires expertise. Also, horizontal advection is a problem, particularly in estuaries where the oxygen concentrations in one location is the result of processes that occur upstream of your sensor. So sensor placement is important.
Seagrasses provide many ecosystem services. Define ecosystem service, and list at least five ecosystem services that seagrasses provide.
An ecosystem service is an ecological function from which humans derive some benefit. Seagrass ecosystem services include erosion reduction, habitat provisioning for fisheries, carbon sequestration, ocean acidification mitigation, tourism and recreational fishing, sediment trapping, nutrient retention and recycling, pathogen reduction, non-use and spiritual benefits, and coastal protection.
Under which conditions would you expect to measure net heterotrophy?
An estuary receiving high imports of organic matter from nearby rivers
Stable isotopes
Another way to identify diet is with stable isotopes, and the book is pretty good at explaining how this works. Most elements have rare isotopes that are useful as tracers, and the ratio of those isotopes is generally expressed as a delta value calculated like this. Delta carbon 13 equals the ratio of carbon 13 to carbon 12 in a sample minus the same ratio for a standard and divided by that standard ratio and multiplied by 1000. Please dont memorize this, but instead learn how stable isotopes are used to identify diet.
Describe three ecological impacts of fisheries activities on estuarine systems.
Answers could include overfishing, habitat disturbance/destruction, bycatch mortality of non-target species, alteration of community structure, alteration of trophic dynamics/food webs
With regards to climate change-related observations and predictions, which of the following are we the least certain about right now?
Anthropogenic climate change has and will increase the size and intensity of tropical cyclones Yes. While this is likely true and current research supports this hypothesis, of all the answers here, we still have more to learn about this.
trophic
As you can see in the figures, invasive species on one trophic level tend to have negative effects on the nativecommunities at the same trophic level.As the log ratio is negative when we look at invasive plants on plant communities, or at invasive animals on animalcommunities.However, , on the other hand, these invasive species tend to have positive effects on other trophic levels. Forexample, invasive primary producers have negative effects on the richness, diversity and evenness of native plantcommunities, but have positive effects on native animal communitie
Mangrove Range expansion evidence
Avicennia most cold-tolerant genus worldwide Expanded salt marshes now well document. Change is consitent with poleward extension of temperature threshold conicident with sea-level rise might be complicated by limited on dispearal or other factors salt marsh to mangrove shift- has important application for ecologicla structure function, global change adaptation
OA in pred verus non
Avoid chamber with chemical cue present, larvae. Most time in non-pred cue settled stage avoid pred cures, but not non predator, does not happen in older larvae in acid water. In untreated water they are attracted to both, cant distinguish Similarly, they do not appear to distinguish between cues ofpredators or non-predators, as they spend the same amount of time in each side of the chamber when both chamberscontain some kind of chemical cue. If this impairment of olfactory preferences in settlement-stage larvae translates tohigher mortality as a result of increased predation risk, this could have important consequences for fish populations.4 case for clown fish And since the examples I have provided are mostly for marine fish, since this field of research is still relativelyyoung, here I am providing an example for pink salmon.In this work they examined the effects of acidification during the development of pink salmon in freshwater andfollowing early seawater entry. They observed that acidification decreased the growth of the fish, as well as theyolk-to-tissue conversion, and maximal O2 uptake capacity.In these figures, for example, you can see clearly that after 10 weeks of exposure, with increased CO2concentration, the length, weight and production efficiency of salmon decrease.In this work they also detected alterations in the olfactory responses as we saw before, and changes in anti-predator behavior.6
Pe
Biological production and consumption dominates the carbon cycle- 93% of inputs were due to autochthonous production- 87% of losses were due to respiration in the estuary- Advective inputs and outputs of organic carbon were minor• Fisheries yield- 1% of total organic carbon inputs- 17% of the net ecosystem production So this example is meant to show you how to go about gathering the data you need to close a budget - in this case a carbon budget - for a large and complex estuarine ecosystem
In what way are the management of estuarine fisheries and aquaculture similar?
Both often require complex, interjurisdictional management. The migratory nature of many estuarine fish requires regulations be set by multiple agencies in and outside estuaries. In aquaculture, multiple types of agencies control and regulate different aspects of culture and catches (e.g., water quality, toxicity of product, introduction of non-native species, etc.).
Boundaries and Timescales
Boundaries should be drawn where flow pathways of materials or energy are unidirectional and where feedbacks are weak- Body of an animal- River/estuary boundary- Burial in sediments- Less clear - boundary between estuary and ocean Timescales should be consistent with the dominant processes being examined- Organism Bioenergetic budgets - hours to days- Estuaries - seasonal, annual• Adjust to data availability The body of an animal is a very obvious clear boundary across which material and energy can flow. bound between river an estuary less clear, I think, is the boundary between an estuary and the coastal ocean, particularly because of this feedback problem. Rivers like the Columbia have extensive plumes that can be fairly productive, and strong tides carry plume water back into the estuary, so while there is a clear boundary between rivers and estuaries - there are feedbacks between estuaries and coastal oceans that make it difficult to quantify fluxes in a budget.
Organism efficiencies
C = P + R + U- C = consumption- P = production- R = respiration- U = unassimilation (excretion & egestion)• P / C = Gross growth efficiency• (C - U) / C = Assimilation efficiency• (P + R) / C = Assimilation efficiency• P / (P + R) = Net growth efficiency- Bacteria growth efficiency Diet also important ne uses lipid biomarkers. Lipids are components of cell membranes, and there are thousands of different types. A few examples are diagrammed on the left side of this slide. The diagnostic parts are the hydrophobic regions of the molecules that hold the membranes together. Some lipids are only found in specific organisms. CLICK - For example, diatoms produce a very specific lipid as part of their cell membranes. In this example, cod fish were fed with copepods that were raised on different food sources, and over time CLICK - the cod picked up lipids into their biomass that originated in the phytoplankton. So cod eating copepods that were raised on diatoms picked up the diatom lipid signal in its biomass, CLICK - whereas cod fed on copepods that were raised on flagellates did not get that signal. CLICK - Cod fed a 50:50 mix got a 50:50 signal.
Ecosystems
Calculate (assume Rday = Rnight)• Pg= Gross primary production = total photosynthesis of an ecosystem (per day)= (Pa x hdaylight) + (Rnightx hdarkness)• R = Total respiration in an ecosystem (per day)= RnightX 24 hrs• Pn= Net ecosystem production (per day)= Pg- R= (Pa x hdaylight) + (Rnight x hdarkness) - (Rnight X 24 hrs)= Pa- Rnight• Pg/R = ratio of production to respiration Then if you assume that respiration during the day equals respiration at night you can calculate CLICK - gross primary production over the whole day. CLICK - This is the sum of apparent daytime production Pa, times the hours of daylight...plus CLICK - the nighttime respiration times the hours of darknessCLICK - R is the total daily respiration in the system, or how much organic carbon is oxidized each day, and you can calculate that from the nighttime rate by multiplying by 24 hours. This relies on the assumption that daytime respiration equals nighttime respiration.CLICK - So net ecosystem production, Pn, combines these two equations, and is the difference between gross primary production per day and total respiration per day. Simplifying this equation gives you net daytime production minus nighttime respiration. So what you do is measure these two things and you can calculate Net Ecosystem Production. Or Pg= reflects nutrient pool size• Boosted by allochthonous nutrients• R = reflects organic matter pool size• Boosted by allochthonous organic matter• Pnand Pg/R reflect steady state balance and not pool size. • A very productive estuary can have a negative or positive Pn• Pn will not tell you if a system is oligotrophic or eutrophic Gross primary production is an interesting and useful number. It reflects the nutrient pool in an estuary because more nutrients usually means more production. Production relies on respiration to recycle the nutrients in that nutrient pool, but if an estuary receives a lot of allochthonous nutrients, then gross primary production will be higher.CLICK - Respiration reflects the size of the organic matter pool because if there is more organic matter available for respiration then respiration is usually higher. Respiration relies on production, but if an estuary receives a lot of allochthonous organic matter from a river, then respiration will be higher.CLICK - But net ecosystem production reflects the balance between the two, as does this ratio of gross primary production to respiration. They do not show the total flux or the pool sizes they reflect. So based on Pn you cannot tell whether a system is highly eutrophic or highly oligotrophic, you can only tell if it is net autotrophic or net heterotrophic. For example a very productive estuary could have a negative Pn or a positive Pn.
Cryptic species are ones that
Cannot be identified as separate species by looking at their morphology
Which of the following elements can be used as a tracer of ecosystem metabolism?
Carbon and oxygen
Different types of introduced
Causal- non self-replacing populations Persistance depends on repated introduction Naturalized relf-replacing pop( for several life cycles/years without/despite intervention(eradication) Invasive self-replace pop produced reproductive offspring, often in lveyr large numbers, away from parent/site of introduction Based on biogeographical aspects Does not mention impact
Top-down control in food webs refers to:
Change in abundance of lower trophic level organisms caused by a predator Yes, an effect of grazing or predation by an upper level of organism on lower trophic levels is called top-down control.
Invasive species can affect estuarine ecosystems in each of the following ways except
Change the salinity of the estuary. cannot Can Outcompete native species for food sources Prey on native species that are naïve to the new predator. Alter the entire biodiversity of an ecosystem.
Effects of changin temperature- reproductive
Change time of flowering- does not match with pollinator presence, activity, etc. Effects also seen on secual reproduction of seagras- Can grow vegetativey also sexually In species Posidonia oceanica- warming and reproduction. Does not flower often- via clones. However with warming has seen an increase in number of meadows that have reproductive shots, reproductive response appears to be thus also a response to stress. So what I just showed you is correlation data, but there is a recent paper where they experimentally simulated aheatwave (explain the figure)...What you see that there are negative effects, with a decrase in grwoth, both during the heatwave, but also oncethe heatwaves is over ... so there are carry over effectsAnd they saw that the individuals that were submitted to the heatwave also produced more flowers.Maybe a reason why they were growing less is because they were investing in sexual reproduction rather than onleaf growht.9 Combat- This increase in sexual reproduction can potentially help counteract this mortality caused by warming, due to the very slow growth rate of a species, high mort in early life stages can suffer, therefore recruitment of new indivudals from sexual repoduction may not offset negative effects of warming-induce mort However fruit can float- arrive to short, dispear large distances and can colonize new areas that have not been as effected by sea level rise. - P.oceanica
Which of the following functional trophic groups is quantitatively least important to energy flows in estuarine food webs?
Chemoautotrophs
Constructing food web models
Choose scale (e.g., seagrass bed, whole estuary, etc.)• Choose currency (e.g., Carbon, energy, nitrogen)• Define components (nodes)• magnitude of production• magnitude and composition of diet• fate of production• Allometric relationships• Allometry = relationship of body size to shape, anatomy, physiology, and behavior For example, there is an allometric relationship between CLICK - the body size or mass of an organism at maturity,CLICK - and the rate of biomass production per unit biomass. CLICK - So larger organisms grow more slowly. This is a solid relationship that can be used to fill in the numbers in food webs when you don't really know how quickly one of your organisms grows. You can use this relationship to calculate population and community production if you have information on organism abundances and body sizes. Also, from the rate of production it is an easy calculation to the rate of consumption using an assumed assimilation efficiency.
tens rule in invasive
Classically the 'tens rule' was thought to apply. That is of the number of species that arrive, only 10% make it to thenext phase, and so on....So for instance, of 1,000 species that arrive to a new area, only 10% would be able to actually survive there, of these100 that would be able to survive, only 10% (that is only 10 species), would be able to establish populations, and,only 10% of those (in this example only one species) would be able to actually spread beyond the area ofintroduction and become invasive.10 however its not challenged 10-100%, indicitating tens doesnt applw very well, and we've been underestimating amount
Sea level rise
Climate change- sea level rise 42-98 cm by end of 21st cent. Est are conservative Processes that influence sea level rise Accretion- vertial accumlation of sediment, comp for an increase in sea level rise- incorporate process of upper marashes, such as root growth can increase height of the bottom surface. Subsidence- processes that lower the level of the bottom Shallow- compaction, decompostion,dewatering in upper sediments- up to 10 meters deep- deep compatcion, due to geological processes such as tectonic activity or genosynclinic downwarping Eustatic sea level rise is global caused by changes in volume of flaciers ice caps- by change in density- volume and temperature relationships. Relative sea level rise- long term- absolute verticaul relationship between land and the water surface. Net accretion is the balance between accretion and relative sea level rise, accretion minus shallow subsidence minus deep substrate and minus eustatic sea level rise Relative sea level risen is not uniform of regional and local changes in land movement and klong-term changes in coastal circulation patterns
Algae response to climate
Co2 increase photosynethis however many species hace carbonate calcium thus ocean acidification could impair biomineralization some species respond postively no response some production actually lover under high co2, no consisten effect c3 many dont know meta for but 85% is c3 calcareous algae responded negatively to increased CO2, you can see that theirbiomas is generally lower, why biomineralizes to produce the carbonate skeleton, but not all species respond the same more variation in response in fleshy algae, some did not respond at all some increase biomass and some actually lower biomass 3 out of 5 fleshy algae become reproductive when exposed to high co2. So this experiment provides evidence to support the hypothesis that high CO2 levels will reduce the ability ofcalcareous algae to biomineralizae, and it also shows that CO2 enrichment will either stimulate vegetative growthor population growth (via reproduction) in some fleshy algae.These results suggest that incrased concnetraton of CO2 would favour non-calcifying algae, and this could haveeffects in changing the abundance of different algal species in coral reefs and other systems....13
Rules
Conservation of Mass/Matter- The mass of a closed system will remain constant; matter cannot be created or destroyed although it can be rearranged.- All inputs of matter must be accounted for in storages or outflows of matter• Conservation of Energy- The total amount of energy in an isolated system remains constant but can change from one form of energy to another- All the energy that enters a system is either stored there or flows out• Steady state is assumed in many ecosystem-scale budgets - No net change in storage over the period considered but of course estuaries are kind of the opposite of closed systems, Storage is often burial in accumulating sediments or saltmarsh soils. Outflows include flow to the ocean, loss to the atmosphere - think denitrification, and human harvest of fisheries.
Ecosystem MetabolismEcosystem Controls
Controls on Pn Pn = total daily primary production - total daily respiration• Pn = Pg - R- But, we can't measure Pg because we can't measure the portion of Pg that the phytoplankton respire- We can measure Pa, apparent daytime primary production, which equals Pg minus daytime respiration by the phytoplankton AND the heterotrophs- Since Pa accounts for all daytime respiration, we only have to subtract nighttime respiration (Rn) to calculate Pn- So Pn = Pa - Rn ight, or Photosynthetically Active Radiation PAR is the primary factor controlling Pa. Daytime Respiration is included in this number Pa, which is why it is called net primary production. If respiration varies then Pa varies. CLICK - Water clarity decides how much PAR reaches the primary producersCLICK - Nutrient availabilityCLICK - GrazingCLICK - And temperature also matters! Nighttime Respiration (Rn) Respiration is controlled by temperature because temperature influences all of the molecular machinery. Enzymes tend to catalyze reactions faster under warmer temperatures. But here again the standard deviations are huge, so other factors matter. CLICK - Here are some of the other controlling factors we discussed in earlier lecturesCLICK - The rate of primary production - more production usually equals more respirationCLICK - Organic matter quality or lability is an important factor. Tasty phytoplankton OM is a lot easier to respire than old soil organic matter.CLICK - Abundance of heterotrophic organisms to carry out the respi Calculate Pn ' High light & low temperature water• Pa = 200 mmol O2/m2/day• Rn = 60 mmol O2/m2/day• Pa - Rn = 140 mmol O2/m2/day• Net autotrophic• Low light & high temperature water• Pa = 60 mmol O2/m2/day• Rn = 120 mmol O2/m2/day• Pa - Rn = -80 mmol O2/m2/day• Net heterotrophic!
eutrophication sea marsh loss
Deegan and colleagues conducted an experiment in Plum Island Estuary, Massachusetts, USA, to examine the longterm effects of eutrophication on salt marshes. They manipulated nutrient levels mimicking moderately-to-highlyeutrophic coastal waters by adding nitrogen and phosphorous to the twice-daily flooding tides for nine years (2004-2012) during the growing season (about 120 days, 15 May-15 September), enriching about 30,000m2 of marsh ineach experimental creek (2 creeks which were enriched and 2 creeks paired as controls). hey found that eutrophication increased above-ground leaf biomass and decreased the dense, below-ground biomass of bank-stabilizing roots, which is illustratedhere by the lower root to shoot ratio in the nutrient-enriched treatment (i.e. the green column). Eutrophication alsoincreased microbial decomposition of organic matter. They also observed the Loss of roots and rhizomes (whichbind sediments and provide drainage macropores) and loss of large organic matter particles (which form air pocketsthat can help drain creek banks), and both of which contributed to increasing creekbank water content. The higherpore water pressure in the bank reduced the frictional shear strength of the soil and increased the sliding force byadding weight to the creek bank. The combination of fewer roots and rhizomes, drag by tidal currents on lodgedplants, more decomposed organic matter and higher water content undermined the structural integrity of the creekbank such that the effects of standard physical forces became enhanced. At low water, the weight of the saturatedbank exceeds the cohesive forces holding it together, the top of the bank cracks and creek-bank sections slidedownward by gravitational slumping. Cracks developed over time with nutrient enrichment, and after seven years ofenrichment, there were more (threefold) and longer (4.5-fold) fractures at the top of the bank parallel to the creek(Table 1) and large blocks of low marsh slumped into the creek.10 Therefore- this change in plant abudnace and decomp from eu altered properties of ecosystem, by reducing geomorphic stablity- creek bank collapse and creek bank marsh converted to unveg mud
Which of the following process must be considered to calculate a rate of Relative Sea Level Rise (RSLR) for any given location? (Select all that apply)
Deep Subsidence Correct Answer Shallow subsidence Correct! The decomposition of organic matter in the sediments Yes, the decomposition of organic matter is part of shallow subsidence, which is a part of RSLR. Correct! Eustatic sea level rise Yes, eustatic sea level is the change in the volume of water in the ocean and is a part of RSLR. Correct Answer Tectonic activity
Sea level rise- estuarines
Depends on net balance of accretion relative sea level rise- history shows can persit for long periods of times during rising sea levels when sediment accretion equals or excees the rate of land subsidice plus elsr. Is currently the case in most wetlands The rate of vertical accretion is a function of the inputs of both inorganic and organic material to the soil (Organicmaterial is mostly derived from the growth of plant roots, whereas inorganic material is mostly supplied assediments from either ocean or freshwater sources. However, many coastal areas are suffering a decrease in thenormal input rates of organic and inorganic materials that would contribute to accretion. - Loss of habitat/ wetland plants due to impacts decrease amounts of organix matters that can arrive. As well as human activies like damming rivers, building reservores or habitat alterations that modify y the hydrofranmic regimes- reduce input of sediments Deltatic wetlands are estimated to disapear b/c of the combo of reduced accretion from damaing and increase in relative sea level rise
Trophic interactions
Direct- Competition- Predation or Parasitism- Mutualism- Commensalism- Amensalism• Indirect• 'Beneficial predator' - e.g. Sea Nettle grazing on Ctenophores removes grazing pressure on copepods• Predation on diseased prey• Keystone species - "a relatively low biomass species with a structuring role in their food web" The book gives a couple examples of how predators can actually increase the abundance of their prey. For example, the sea nettle grazes on both ctenophores and copepods, but it is more effective grazer on ctenophores. Ctenophores graze on copepods, so when sea nettles are around in an estuary the copepod populations can actually increase because the seanettles wipe out the ctenophore population. And since the nettles also graze on the copepods, they actually increase their food supply by wiping out the competition and feeding at a lower trophic level. Predators can also benefit their prey communities by selectively grazing on old and diseased organisms. The book did not have any specific examples of this for aquatic systems, but I think you can imagine it. The slow sick fish are the ones that get caught first.CLICK - Keystone species is kind of an old concept, but it applies in most aquatic systems to some extent. It is defined as.... There is rarely a single keystone species but often there are Trophic interactions• Direct- Competition- Predation or Parasitism- Mutualism- Commensalism- Amensalism• Indirect• 'Beneficial predator' - e.g. Sea Nettle grazing on Ctenophores removes grazing pressure on copepods• Predation on diseased prey• Keystone species - "a relatively low biomass species with a structuring role in their food web" several low abundance species that are "keystone-like" organisms that influence the structure of food webs. I think of manatees or sharks, and I see something like this in lakes in the arctic where I work. Some of the lakes are shallow and they freeze to the bottom every winter. If there are no big streams going into or out of these lakes, then they usually do not contain any fish. Lakes without fish have a very different biological community than lakes with fish. Just looking into these fishless lakes you can see big populations of shrimp-like crustaceans and other small things. Those guys are almost totally absent in lakes with fish. So the presence of a predator changes everything in a food web and shifts the biomass remarkably
Mangrove- climate change
Distribution modeling suggests the hypothesis that mangrove-salt marsh ecotones around the world persist near climate-related thresholds, whereby small increases in temperature could lead to large increases in the relative abundanceof one species vs. the other. Steady increase in cover- florida receased decrease after freeze Winter- critial period to survial and affects range expansion capacity Can we predict change? You can see that themangroves exhibit a threshold response to extreme cold, with large reductions in performance at temperatures of9 between -2 and -6C, but these threshold temperatures are different amongst species. Black mangroves were the most freeze tolerant and white mangroves were the least tolerant. You can see that even attemperatures of ca. -8C, black mangroves do not suffer high photoinactivation,, whereas the white mangrove, depicted inthe blue dots, already suffers high levels of photoinactivation at ca -2ºC. These result match the observation that blackmangroves have the most northward distribution in Florida, followed by red mangroves and then white mangroves.9 They estimated that the range limits of mangroves will move northward by ca. 2 to 3 km a year over the next 50years, with an expansion rate for black mangrove of about 3.2 km per year, and of 2.2. to 2.4 km per year for theother two species
Which of these statements are true? (check all that apply)
Ecological extinction due to overfishing / harvesting of species precedes any other impacts that humans have had in the history of wildlife
seminal paper by Jeremy Jackson and colleagues published in Science in 2001
Ecological extinction due to overfishing/harvesting procedes any other impact that humans have had in the history of wildlife or world. Given more in pollution, habitat destruction climate change, etc Harvesting is cosndiered the oldest impact due to this we might have a bias since its after so many exctinction events. And we have likely dramatically changed them in recent ecological history, way before we started studying them. Shifting baselines- consider the systems of normal or pristine, is prob very different that what normal actually is
Compare ecological pyramids and food web networks- how do they differ and how are they similiar
Ecological pyramids are one way of portraying the overall structure of food webs. Ecological pyramids appear as stacks of rectangles where each rectangle represents the aggregate abundance, biomass, or energy flow at an integer trophic level. Pyramids of biomass are interesting because they may be inverted, wherein biomass accumulates in long-lived organisms at high trophic levels. In contrast, pyramids of energy flow are always wider at the bottom. The decrease with each trophic level represents aggregate loss of energy from the food web. Directed graphs or network diagrams illustrate all the nodes in a food web and the connections or trophic flows among them. Network diagrams visualize the most detailed information about a food web and may illustrate the same quantities of energy flows as a pyramid. However, aggregate characteristics of the food web may be less evident.
Eco system provided by salt marshes
Ecosystem processes and functions Ecosystem services Ecosystem service value examples Generates biological productivity and diversity Raw materials and food US$23.06 ha-1 yr-1 net income from livestock grazing UK Attenuates and / or dissipates waves Coastal protection US$8,236 ha-1 reduced hurricane damages, USA Provides sediment stabilization and soil retention in vegetation root structure Erosion control UNAVAILABLE Provides nutrient and pollution uptake, as well as particle retention and deposition Water purification US$785-15,000 acre-1 cost savings over traditional waste treatment Provides suitable reproductive habitat and nursery grounds, sheltered living space Maintenance of fisheries US$6,471 acre-1 and $981 acre-1 value fro recreational fishing for the east and west coasts of Florida, respectively $0.19 - 1.89 acre-1 value product blue crab fishery in Gulf Coast Generates biogeochemical activity, sedimentation, biological productivity Carbon sequestration US$30.5 ha-1 yr-1 Provides unique and aesthetic landscape, suitable for diverse flora and fauna Tourism, recreation, education and research $47.7 person for otter habitat creation and $1.8 person for protecting birds, UK Ecosystem services provide by salt marshes Barbier et al. 2011 WikimediaUSGS And here we have the list for salt marshes. You can see that they also provide us with raw materials and food, coastal protection and erosion control, fisheries, water purification, carbon sequestration and cultural ecosystem services. Economic evaluations for salt marshes are more available than for other estuarine ecosystems. 14 Current decline- 20%- mean estimated level of sea rive 45% max increase by 2% under mean scenario but loss 39% under max For example they estimate a loss of productivity (macrophyte biomass) of about 8% to 28%, loss of this wastetreatment (by nitrogen accumulation in soil, potential denitrification) will also decline. For example, nitrogensequestration in the soil is estimated to decline between 4 and 23% and denitrification is estimated to be lostbetween 4% and 25%16
Food web efficiencies
Ecotrophic efficiency = fraction of production by a trophic group that is used by the next higher level, harvested or exported (i.e., does not become detritus).• Trophic transfer efficiency = fraction of production by a trophic level that results in the production at the next higher trophic level- ~10% "rule of thumb" Here are a couple efficiencies I want you to learn. In fact, this is the first learning outcome of this lecture. These organism efficiencies are averaged among the organisms involved in each trophic transfer to calculate food web efficiencies, which are very important for food web modeling. Ecotrophic efficiency is the fraction of production that is either used by the next higher level, harvested, or exported. In other words it is the fraction of new production at a trophic level that does not become detritus in the next trophic transfer.CLICK - Trophic transfer efficiency is the fraction of production at one level that results in production at the next higher level. This is an important number, and it tends to vary around 10% for most trophic levels in aquatic ecosystems. Please take some time to absorb these concepts of organism and food web efficiencies. If you understand these concepts you will be far on your way to understanding how changes in food webs influences ecosystems. cont So say if in a food web 10% of primary production becomes new pelagic herbivore biomass, 70% goes to herbivore respiration, and 20% goes to detritus, what is the ecotrophic efficiency of primary producers in this food web? CLICK - 80%. What is the trophic transfer efficiency? CLICK - 10%. What organisms benefit when ecotrophic efficiency of primary producers is low? CLICK - Bacteria. What organisms benefit when the ecotrophic efficiency of primary producers is high?CLICK - carnovores. Food web efficiencies matter because they decide how much primary production is converted into higher trophic levels and how much goes to bacteria and to respiration and mineralization. CLICK - At 10% trophic transfer efficiency, you can imagine that every step in a food web drastically reduces the amount of material. This is why very long trophic pathways are rare or not really possible. CLICK - The longest pathway in this diagram has 8 trophic steps, with trophic level resetting to 1 when material becomes detritus. But no organism has an average trophic level much greater than 5 because a substantial amount of material is respired at each trophic level. So even though Large Fish are trophic level 7on this trophic pathway, they also receive material and energy much more efficiently from shorter pathways that brings their average trophic level down a lot.
Which of the following statements is false?
Estuaries contribution to blue carbon sequestration is small relative to their area
temporal trends in estuaries
Estuaries key locations of human settlement- numerous resources This is a review performed by Heike Lozte and colleagues, published in 2006, looking at changes in abundance of differentgroups of plant and animals in twelve different estuarine areas through time, and it is also incorporating this historicalperspective.It separates into different time periods:pre-humans (Pre), a Hunter-gatherer period (HG), an Agricultural period (Agr), the establishment of a market-colonial system(Est), the development of this market-colonial system (Dev), and then two periods of Global market, a 1st one during the 1sthalf of the 20th century (Glo1), and a second one for the 2nd half of the 20th century (Glo2).As you can see, human populations basically starts increasing dramatically about 300 years ago, that is after theestablishment of the market-colonial system.6 Relative abundance of marine mammals, dramaticlaly decreased from established market-colonial period Collapse in present today dramatically altered in 300-150 years 90 depleted of fermely improted species and have destroyed 65 seagrass and wetland habiat
Sea level rise est 2
Estuarine habitat migrate upslope. Wetland-upland transition, here could be conversion of upland areas to wetlands as frequent floodingreaches farther upslope and wetlands "migrate" inland Will be truncated b/c human impact or modification, not allow establishment of plants- Be squeezes between the upper limit established by human act, lower limit det by sea level. can disapear is relative sea level rise keeps rising If wetlands can not keep pace, with rates an increase inundation frequency and duration could lead to a shift in dis or gegatived habitats arocss a wetland, thus many salt marsh plants could change with a change in sal and flooding Expection lower marsh areas unegatived muflats with increase sea level rise, or even subtidal waters in long term. Some potential to escape sea level rise, but loss is restricted because of the transofrmation of lang upslode- so not all could overcome this sea level rise All upland transition, high and mid-marsh habitats projected to be lost by 2100. loss of pickleweed could affect many tidal marsh wildlis epcies- several endangered species
What are the primary causes of catastrophic mortality in estuarine fishes?
Eutrophication, leading to nighttime depletion of oxygen and/or benthic production of b. H2S c. Harmful algal blooms d. Hypersalinity e. Cold or hot spells, particularly effective in shallow estuaries f. Pollution from land-based sources such as agricultural run-off and pesticides
For different areas of the world, climate projections indicate both increases and decreases in freshwater inputs to coastal systems. Increased freshwater inputs can lead to both beneficial and detrimental impacts. Which of the following would generally be considered a detrimental impact? (Select all that apply) Correct!
Excessive nutrient delivery to the coast, leading to eutrophication Yes, coastal eutrophication is already a problem in many coastal regions. The increased runoff may also lead to problems with toxic pollutants. Yes, high levels of heavy metals and organic pollutants are commonly associated with runoff.
Other examples of effect of Ocean acid
Fish effects- behaviours traits, with settlement stage of larvae, channels where they moified ph of the water, response of the fish to different chemical cues, that are likely going to affect settlement, attracting or deterring the fish fish that use anemones as their home co2 verus acidified water, cue = higher timer , even on cures we expect them to avoid. Resposent o anemone- home cue is decreased under scidified water OA is imparing the olfactory discrimination capacity of clownfish. no physical change therefor must effect of transfer chemosensory siginals within neurologicall systems
Ecological functions by mangrove
Generates biological productivity and diversity Raw materials and food US$484-585 ha-1 yr-1 value of collectedproducts ThailandAttenuates and / or dissipates waves and wind energy Coastal protection US$8,966-10,821ha-1 value for stormprotection ThailandProvides sediment stabilization and soil retention invegetation root structureErosion control US$3,679 ha-1 yr-1 annualizedreplacement cost Thailand Provides nutrient and pollution uptake, as well as particleretention and depositionWater purification UNAVAILABLE Provides suitable reproductive habitat and nurserygrounds, sheltered living spaceMaintenance of fisheries US$708-987 ha-1 value increased offshorefishery ThailandGenerates biogeochemical activity, sedimentation,biological productivityCarbon sequestration US$30.5 ha-1 yr-1 Provides unique and aesthetic landscape, suitable fordiverse flora and faunaTourism, recreation,education and research UNAVAILABLE his is the list of ecosystem services provided by mangroves according to the review by Barbier and colleagues.We see that mangroves provide similar ecosystem services that those provided by seagrasses, and interestinglymany more economic evaluations have been obtained, perhaps because being a non-subtidal system, studies areeasier to carry out? Or perhaps because some of the services they provide are greatly and directly used by the localcommunities... I am not sureFor example, for mangroves in Thailand, it has been estimated that one hectare of mangrove forest can provideabout $500 a year in terms of food and raw materials, or a value of about $9,000 in terms of coastal protection.8 Value- fisheries langing postively relat4edx to local abundance of mangrove, produceive area in mangrove- water fringe in nursery mangrove related fiah and crap- 32% of small-scale fisheries Carbon- Main con of carbon sink global aboveground 160 mega grams per hectare, belowground is 16.7 mega carbon- 950 mega grams in ground stoarge 17% of worlds bleu carbon resovoir many areas actually 50%, belowground stocks critical to providing c sinks New habitat different- emissions high, reaching values to 1000 to 3000 grams compared to amazon tropical forest lostt, mangrove habitats implies much larger loss A typical steak and shrimp cocktail dinner would burden the atmosphere with 816 kg CO2.This is approximately the same quantity of GHGs produced by driving a fuel-efficient automobile from Los Angelesto New York City.13
Ecological functions by seagrass
Generating productivity and diverstity, they provide humans with raw mat and food, provide habitat for many species of commerical interest(fish and shellfish) cont to maintenance of fisheries 3-d complex structite that attenuates or disspates wave action- they contribute to costal protection- also enchance the trapping of particules contributes to water clarift Incorprating nut and pollutations seagrass beds further cont to water purification= complex root and rhizome system stablis sediment, enhance soil retenion, and contribute to erosion control. Also generate biological productivity, sediment and biogemical acityies, carbon sequestration Cultural ecosystem servies- providing clean waters for siutable fir diverse fauna and floara, tourism recreation education and research Seagrass high abudance,=more fish, lower - complete loss Seagrass tore between 4-19.9 grams of organic carbon current loss 300 grams per year
How do the climate change impacts of increased storm frequency and magnitude, increased CO2 in the air and water, and ocean warming affect benthic macroalgal communities?
Greater storm frequency and magnitude can result in higher levels of disturbance that decrease macroalgal growth and distribution. Increased CO2 may enhance macroalgal production. Ocean warming (and the greater incidence of marine heatwaves) negatively impacts macroalgal growth and can lead to widespread loss.
Ecosystem MetabolismEcosystem Controls23
Here is the relationship between net ecosystem production and gross primary production for many different estuaries. Nutrient enriched estuaries tend to be net autotrophic with positive Pn, while organic matter enriched estuaries and salt marsh estuaries tend to be net heterotrophic. And the degree to which these systems are net autotrophic or net heterotrophic seems to depend on the gross primary production of the system.So spend some time making sure you understand net ecosystem production - what it means and how to calculate it. This is becoming a very important way to describe the metabolic characteristics of estuaries.
Seagrass certain nut and chem traits
However, if nutrientavailability increases in the environment , this may cause a change in these traits and thus in plant consumptionpatterns.For example, if nitrogen is more available in the water or the sediment, it is incorporated to plant tissues, which willchange the C/N ratio of the leaves, and thus could make the plant more susceptible to consumers as it becomesmore nutritious. Indeed there is a positive correlation between nitrogen content in the leaf and herbivory ratesuffered, as you can see in this figure which is a worldwide review that examined grazing in terrestrial and aquaticsystems in relation to plant nitrogen content. In addition, changes in nutrient availability may also change theproduction of chemical defenses. Indeed, the resource availability hypothesis suggests that when resources are low,plants often invest more in secondary metabolites to protect themselves against consumers, because they cannotafford to lose any of the little biomass they produce. On the other hand, when resources increase and become morereadily available many plants switch from producing so many defenses, and instead they invest in growth. Thus,since nitrogen is a limiting resource for seagrasses, one may expect that under eutrophication seagrasses will reducethe production of chemical defenses, and this could make them more susceptible to being consumed.10
Not all even
I already mentioned that not all areas of the world are going to be equally affected by warming, and there can bestrong regional differences.A work published in 2014 has shown that during the twentieth century, temperate regions along poleward-flowingwestern boundary currents have warmed 2 to 3 times faster than the global mean .In this figure you can see the trend in changes in sea surface temperature recorded from the year 1900 to 2005.The redder areas are regions where there has been an increase of 1 degree Celsius or more during the last 100years.Indeed, you can see that many areas which have western boundary currents, such as Japan, eastern Australia, theEast coast of the US, northern Brazil, or southeastern Africa , have significantly warmed.In addition to the western boundary currents, other oceanographic features also transport tropical water towardstemperate regions. The poleward- flowing Leeuwin current along the coast of western Australia is a prime example.In 2011, a strengthening of this current caused a marine 'heat wave' in which the coastal waters along much ofwest Australia increased by 2-4ºC for approximately two months. The Mediterranean Sea is also a region that haswarmed much faster than the world mean.12 Western boundary currents- expansion of tropical herbivorous fish, into temp areas
Harbor
Impacts of sediment burial on seagrassRoca et al. 2014This is another example of habitat alteration from a human activity; in this case there was a construction of aharbor, which caused an important increase in sediment deposition rates and increase of sediment organic matter.The representation of this event is (highlighted as the grey area in the two figures, where we see the changes inshoot abundance before and after the impact in a bed that was affected vs. a nearby bed that was not.You can see that this burial event caused a strong mortality of seagrass (reducing the population to about 50% ofits initial abundance in the impacted meadow, and, importantly , three years after the sedimentation event,seagrass populations had not recovered, while in a nearby population (the one called control) where thissedimentation had not occurred plant abundance had actually increased after three years.So long lasting effects of a one-time human disturbance.
temperal trends
In 2011 Essl and colleagues conducted a review examining the relationship between metrics that represent human populationand economic growth and introduction of nonnative species in Europe, and assessed whether historical (1900) or contemporarydata (2000) on human activities explained current patterns of introduced species richness.In particular they examined population density, Gross Domestic Product, and Exports across the last century and divided thedata into 50 year units.You can see that there has been an increase in these parameters throughout the last century, and particularly during the last 50years.Then they applied models to see which of those human population variables better explained current patterns of introducedspecies.These figures show the weight of the model fit when using the 1900s socioeconomic data (in grey) vs. the weight when usingthe 2000 data.Interestingly, you can see that for many groups of organisms analyzed, such as vascular plants, bryophytes, fungi, mammals,amphibians, fish and aquatic invertebrates, the current patterns of numbers of nonnative species are better predicted by thehistorical socioeconomic indicators of the 1900s than of the present day indicators (2000).So, current patterns of alien-species richness appear to reflect historical rather than contemporary human activities, indicatingthat there is a substantial historical legacy for patterns of species introductions.Therefore, the consequences of the current high levels of socioeconomic activity on the extent of biological invasions willprobably not be completely realized until several decades into the future, a concept that the authors call the "invasion debt".14
What does balance mean from a quantitaitive food web model perspective
In the context of a food web, "balance" refers to the sum of inputs to each node and the sum of outputs from each node being equal. If the flows at every node are balanced, then the biomass at each node is in steady state, or not changing.
Implications of OA for other calcifying organisms
Increase in co2 leads to increse in co2 in oceans- carbon equilibrium, decreasing ph as well as the conc of carbonate ions. With the decrease in darbone ions, decrease in saturation state or omega, this decrease in the vailabilty of calcul carbonate - effect on organism that use it. Many organisms in est undergo calcification, Planktoniic-corals and bivales Cocclithophores- major calcum carbonate producer in worlds oceans, thirs of total marine caco2 production. strong postive correlation between carbonate ion concentrations in the water and biomass of these species. negative relation between mass and decrease ph or increse co2 This suggests that different species or morphotypes ofone species may be able to adapt and respond differently to present and future increased levels of CO2.4
Eutrophication: Increased nutrient inputs
Increase in nitrogren last 50 years worldwide translate to more nitrogen in estuaries increased are from wastewarer and fertiliziers, so human activities are clearly increasing N contents in estuaries, thus affect estuary chemistry
Budget Analyses - Chesapeake Bay
Is the estuary an efficient trap for organic carbon resulting in organic enrichment of estuarine sediments?• Is physical transport of organic carbon larger or smaller than biological production and losses? to three large boxes, similar to the more detailed box model I showed you earlier for the patuxent river. CLICK - They calculated the salt and water balances to calculate coefficients of exchange between the boxes and CLICK - used data from several sources including their own measurements and measurement made by the EPA to calculate the fluxes into and out of each box. They then summed the fluxes into an overall budget. he budget here is nearly balanced between inputs and outputs. Net ecosystem production is positive, that is the P-R here, which is these two production fluxes on top minus the two respiration fluxes on the bottom. And that is about the same as the inputs from outside the estuary, minus the outputs to the ocean, burial, and fisheries.
What is pristine?
Issue we'e not bringing back the predators that have potentially controlled population ins the past like sharks so converse seatrutles but not conserve sharks- detrimental impacts- mirror of wolves on land This is representedhere conceptually; In a truly pristine setting, for instance, sharks would be abundant, and thus abundance of turtleswould be relatively low, and there would be extensive seagrass meadows harboring large and complex seagrassesthat create complex structure and harbor high biodiversity within them. ith decreasing shark abundance turtlepopulations would increase, and changes would occur in seagrass meadows, losing area and / or suffering areplacement towards less complex, simpler structure, and more palatable species that form more simplifiedecosystems with less associated biodiversity. Finally leading to overgrazing and seagrass meadow loss. So this pattern of shark presence mediating the effects that sea turtles have on seagrass meadows could be notjust an anecdote but potentially quite a general trend; it would be interesting to see if sharks were re-introduced inthese areas, if there would be changes in the seagrass populationsTherefore, healthy populations of both sharks and turtles are likely vital to restoring or maintaining seagrassecosystem structure and function.15
History
Johnstone (1908) N budget for North Sea- More N flowed into the North Sea than was returned in fisheries landings• 1960s - rising awareness of nutrient pollution- led to development of nutrient budgets for lakes- many estuary nutrient budgets published in the 1990s• Net Ecosystem Metabolism• Land-Ocean Interactions in the Coastal Zone (LOICZ)- Effort to describe connection between nutrient pollution and eutrophication in estuarie n other words the nitrogen inputs did not all turn into organic nitrogen in fish biomass hese budgets can tell you a lot about an estuary, including its net ecosystem metabolism began in 1993
Food webs in a spatial mosaic
Just the fact that estuaries are shallow creates two big interacting environments - the pelagic and the benthic - so transfers of material and energy between the two have to be considered in these food webs. Benthos usually consume a significant fraction of total production in estuaries.Suspension feeding organisms like oysters can exert grazing control on plankton. Many fish and estuarine wildlife like birds feed on benthos.Another example of an interacting environment is seagrass beds. CLICK - In tropical estuaries many organisms live in mangroves or are associated with coral reefs, but they migrate to very productive seagrass beds to feed. And then they go back to the mangrove or coral reef.CLICK - In temperate estuaries many fish and birds travel to seagrass beds to feed. Also, many organisms like blue crab use seagrass beds for shelter during juvenile stages.
Consequences of herbivore expsansion
Latitudal gradient of herbivory pressure- much stronger in tropical then temperature, herb is fact critical in maintaining healthy subtidal reefs. High density and abundnace of herbivoreosu fish that consstand forage- needed by coral reefs and needs to be high biodiverstiy On other hand Temperature reefs harbor algal habitats such as kelp forests, herb kepy low, this low is needed to keep levels of health on kelps and algae, provide habitat for many fauna and flora. Therefore if tropical fish, ver voracious expand on theses temperature areas, the pressure would increse on these lands having negatively effects- and loss. See in some areas already Rabbitfish- Japan As well as hebivory fish, some coral species also expaned- depletion of algae they are able to colonize Barren area typical of eastern med sited due to rabbitfish shifts Diverse forest, that is a nursery to barren that can not support diversity As you can see, some species such as dugongs, turtles, parrotfish and rabbitfish are predicted to expand 200 to 400km by the year 2100, whereas others such as the black swam are predicted to maintain their distribution rangewhile the temperate blue weed whiting (Haletta semifasciata) will likely see a major loss on its distribution range.18
Increasing temperatures and more frequent and intense storm events associated with climate change are predicted to be stressful for seagrass populations globally. How might the biological characteristics of a seagrass species affect its response to climate change? Specifically, describe situations in which (a) reproductive strategy, (b) phenotypic plasticity, and (c) sensitivity to environmental stressors affect how a seagrass species responds to climate change.
Long-lived species that reproduce with rhizome elongation rather than seeds or fragmentation (e.g., Posidonia) may be slow to recover after storm events. However, species that reproduce readily by seed may be able to quickly recolonize a disturbed area. (b) Species with greater phenotypic plasticity will be better able to acclimate to stressors associated with climate change. For example, species that can elongate their leaves and stems in response to increased turbidity will be able to withstand more frequent and intense storms. (c) Species that are sensitive to temperature increases (e.g., Zostera) will experience mass mortality events in response to heat waves associated climate change.
What can cause estuarine biomass pyramids to become inverted?
Longer average lifespan of higher trophic level organisms
Which of the following statements identify effects of climate change on estuarine wildlife? (Select all that apply)
Loss of mudflats, beaches, and marsh habitat due to increased erosion. Yes, sea-level rise associated with climate change can lead to increased erosion in estuaries. Correct! Increased nest flooding of tidal marsh breeding species. Yes, sea-level rise associated with climate change can lead to increased nest flooding.
Pullulation
Low-level exposure can impact reproduction, and high-level exposure to mercury damages thecentral nervous systems zooplankton mortality in copepods also bind to sediment, benthic organisms more susceptible to being threatened hat the larval phase of brown and white shrimp were able to detect the presence of a pollutant and avoidit. And while these larvae are attracted to estuarine water, the presence of this chemical inhibited this attractions.In this case, this behavioural effect could have important implications for the distribution of zooplankton inestuaries which are polluted if they find those waters repellent. have shown that generally crustaceans and echinoderms are more sensitive to pollution while annelids andnematodes are more tolerant,Thus pollution may create shifts in community composition and relative abundance of different species. In fact,Capitella capitata is a species that is commonly used as a bioindicator of pollution, as it is very tolerant species.4
Macroalgae can contribute to "blue carbon" sequestration and storage in marine ecosystems. This is considered one type of "nature-based solution" to climate change by removing CO2 from the atmosphere. Describe the ways in which marine algae contribute to long-term carbon storage in the ocean.
Macroalgae have high rates of primary production which removes carbon dioxide from the atmosphere and fixes it in plant biomass. Some of the macroalgal biomass may be exported to deep waters where it is buried for long periods of time (decades to centuries).
What are the major components of bioenergetics budget? How can these components be used to explore trophic efficiencies
Major components of a bioenergetics budget include consumption (C), which accounts for the input of organic matter to a consumer organism, and production (P), respiration (R), and unassimilation (U) which in combination should be equal to consumption (C = P + R + U). Several key trophic efficiencies can be defined as ratios of these components, including gross growth efficiency (GGE = P / C), net growth efficiency (NGE = P / [C-U]) or equivalently (= P / [P+R]), and assimilation efficiency (AE = [C-U] / C). The components of a bioenergetics budget for an organism or group of organisms at a node in a food web do not provide enough information to characterize several important efficiencies of a food web, such as ecotrophic efficiency (EE) or trophic transfer efficiency (TTE). To calculate these, it is also necessary to have information about the food web, such as how much of the production in a node is retained in the food web and transferred to the next higher trophic level.
Which of these statements are true? (check all that apply)
Marine reserves can cause the decrease of seagrasses Marine reserves enhance the export of fish biomass and larvae outside the reserve Sea urchin abundances in marine reserves are lower than outside marine reserves
Which of the following statements regarding the ecosystem services offered by coastalmarshes is true?
Marshes are more important for the storage and retention of water than coral reefs
How do mechanistic methods differ in their development from statistical models
Mechanistic models are developed by creating linked equations that represent specific rates of biological, chemical, and physical processes, while statistical models are developed by generating empirical relationships (e.g., correlations) between observed data (concentrations, abundances, densities)
Effects of changing temperature
Normally a bell-shaped curve in response to an increase in temp. Metabolic rates increase more or less linearly with temperature reaching an optomin of max metabolism. Temperature is too high- indivudual or cell cannot function properly- algae seagrass Negatively affected in two northerly estuaries, estuaries have suffered a decline of the main submerged benthic primary prod. Plausible- rise in sst has negatively affected the abundance of seagrass and ulva. Seagrass2- Biomass change Higher temperatures steady decrease in the leaf biomass of juveniles, temperature may have negative effects, enhancing respiration more then photo. No negative effect or increase on adult though in experiment, higher death in field experiment Higher temperature= higher mortality 50 day experiment not long enough to netect effect. Warming may also enhance plant mort by increasing respiration of microbial communities associated with sediment, potentially enhancing sulfate reduction and thus sulphide toxicty. Intrusion of sulphide into seagrass leaves siginificantly increased with increasing sewater temperatures, thus supporting this idea of additonal negative effects of warming on plant mortality.
Alter and indriect eeffects
Not only filing or drainging of wetlands but construction of channels, dredging of canals, con of dams, diversion and uptake of freshwater For example the construction of dams upstream not onlymodifies the quantity, and timing of freshwater that will arrive to an estuary, but by stopping the flow of water, animportant amount of the sediments that are transported in the river get deposited on the bottom of these dams,so the natural input of sediment that would typically arrive to the estuary can be dramatically reduced. ... so thiscould lead to loss of the estuary. - eeffects on migratory species- life history interferance climate change- hydrodynamics DAMS causing dramatic shortage of freshwater input, which affects soil salinity, increasin igt, decreases the amount of sediment particles that arrive to the delta
riverine dynamics
On the other hand, riverine dynamics can have both positive and negative effects on coastal ocean pH by modifyingthe availability of carbonate ions. For example, agricultural practices in the Mississippi River watershed have, overtime, increased the total flux of carbonate alkalinity (bicarbonate and carbonate ions) from rivers to the ocean,resulting in a slight increase in the water aragonite saturation state. In other regions such as the Gulf of Maine,spring snowmelt waters with relatively lower carbonate ion concentrations reduced the aragonite saturation stateof coastal waters.In this figure you can see the value of omega, ranging from about 0.2 to 2 along the Kennebec river estuary inCasco Bay, Gulf of Maine. You can see that the river has a strong influence in decreasing omega, which reachesvalues close to 0.4 in some areas. coastal upwelling can also enchance acidifcation of eestuarine watersm cold deep water to surface, high conc of co2 and are rich in nuttrients., very shallow sometimes n addition, the CO2 content of upwelled waters is increasing because ofanthropogenic emissions.13
Examples of management approaches to battle declibe
One example is the creation of Marine reserves or Marine Protected Areas (MPAs), which are areas where fishing isprohibited and which allow for this reversal of fish population decrease, enhancing recovery of populations (inaddition to other biodiversity protection interests...) - target larger predatory fish and are generally main harcest species- they do work increase abundance, size, lifespan and reproductive potential also enhances export of biomass/export of larvae outside the map fueling recovery of populations outside the reserves Ecological effects- abundance higher, allowed the recovery of kelp so a clear example of changing abundance of predators through protection- but decreased abundance of herbivous like urchins trophic cascase Ecological effects may take years or decades sometimes herbivorous and predatory both abundance lower abundant of fleshy algae- and sea urchin decrease
What influences the ability of marshes to maintain equilibrium elevation? (Select all that apply)
Organic matter supply elowground biomass Yes, belowground biomass strongly impacts the ability of the marsh to trap sediment and maintain elevation Correct Answer Sediment supply Not temperature- does impact marsh veg
Hypoxia
Oxygen is critical for most marine organism less than 2 mg per lit- arguement for at 5ml anoxia oxgen levels are below detection, typ .2 Very variable in est depending on flow intensity / water stratification, organic matter loads (natural / anthropogenic.......) Forexample, sediments in mangroves are often very anoxic because they accumulate a lot of organic matter (thewrack, which makes them good for "blue" carbon storage). low oxgen predominant feature in parts of the world- human activities and particularly eutrophication high abundance of sulfer in marine waters- under low oxygen conditions bac might use sulfate instead of oxygen to perfomr resp- relasing sulfide into the water They observed that overall, SURVIVAL UNER HYPOXIA IS REDUCED, ON AVERAGE, 30% IN MARINE BENTHICCOMMUNITIES when EXPOSED TO HYDROGEN SULFIDE. NEGATIVE DIRECT EFFECTS OF HYPOXIA (LOW OXYGEN) MAY BE AGGRAVATED BECAUSE HYPOXIA OFTENINDUCES INCREASE IN SULFIDENURSERY HABITATS / HABITATS FOR MANY MOLLUSCS FISHERIES12
What word can be used to describe an estuary where respiration exceeds primary production?
P/R Ratio < 1 Heterotrophy No, autotrophy is the case where primary production exceeds respiration.
Ecosystems (autotrophs+heterotrophs)
Pa = Apparent net daytime production = Pg - Rday(Pg = Gross production by autotrophs)(Rday = Respiration by autotrophs and heterotrophs)• Rnight = Nighttime respiration rate (by autotrophs and heterotrophs) At the ecosystem scale, our measurements combine the activity of autotrophs like diatoms and seagrass with the activity of heterotrophs like bacteria and fish. And we split the measurement into the things we can measure during the day and the things we can measure at night. CLICK - We can measure apparent daytime production, Pa, which is a little like net primary production of autotrophs if it were measured only during the day when they are photosynthesizing, This measurement of apparent daytime production (the a stands for apparent), is the difference between gross primary production by autotrophs during the day and respiration during the day, with that respiration including autotrophic respiration and heterotrophic respiration.CLICK - Respiration during the night also includes both autotroph respiration and heterotrophic respiration. Just like with apparent daytime production you can measure this. You usually make this measurement at night or in the dark, and you assume that gross primary production equals zero and that all you are measuring is respiration. Measurements; Bottle incubations and open water Bottle: Sample water is captured in gastight bottlesCLICK - some are incubated in the dark to measure nighttime respiration.CLICK - you measure the change in oxygen in the bottle over time. CLICK - and that is nighttime respirationCLICK - then you incubate some bottles in the light. you measure the change in oxygen, which is created by photosynthesis and consumed by respiration, and that is apparent daytime production
Autotrophs only
Pautotroph = Pg = Gross primary production of a plant or group of autotrophsBiomass + respiration + released OM• Rautotroph = Respiration of a plant or group of autotrophs• NPP = Net primary production = Pg - Rautotroph• Cannot measure Pg directly Autotrophs produce new carbon and they do three things with that carbon. They grow and produce new biomass, they respire some of it for energy, and they release some of it into the environment. If you add those three things up that is gross primary productionCLICK - the second term is respiration by the autotrophsCLICK - Net primary production or NPP is the difference between gross primary production by autotrophs and respiration by autotrophs. CLICK - The problem here is that gross primary production CANNOT BE MEASURED DIRECTLY. You cannot measure gross primary production because autotrophs respire some of the organic matter that they produce while they grow. But you can measure NET primary production by autotrophs, and when you measure that you are measuring the difference between GPP and autotrophic respiration.
Pe Pat
Pe for Salt- Pe assumed to be zero because it is a conservative constituent• Pe for Oxygen- Balance between production by autotrophs and consumption by heterotrophs• Pe for Inorganic nitrogen- Balance between production by microbial mineralization and consumption by organism growth• Pe for Silica- Balance between production by dissolution of diatom frustules and consumption by diatom growth et production in the surface, and this production was particularly high in the spring and fall when phytoplankton bloomed. And in the bottom boxes they found net consumption of oxygen, and this consumption was particularly high in the summer months following the spring bloom. The way the calculations work is that, by definition Pe for salt -CLICK - the net production of salt and other conservative constituents would be zero and all the points would fall right on this line. Dissolved inorganic nitrogen consumed in the estuary in the winter and spring in both the surface and the bottom layers, but in the summer and fall it is produced in the bottom layers in a big way, presumably by heterotrophs recycling nutrients by respiring detrital organic matter and releasing ammonium Silica produced in bottom year round presumably by dissolution of mineral silica that is sitting in sediments- diatoms bloom sink presumably by dissolution of mineral silica that is sitting in the sediments, but notice how the rate really picks up after the spring bloom, which shows that diatoms in that bloom sink to the sediments and don't just wash out of the estuary.CLICK - Silica is consumed in the surface waters, presumably by growing diatoms, except in mid summer when there is net production in the surface.
Ecosystem Metabolism Terms and Definitions
Pn Net ecosystem production is a number that brings together a lot of information about organic matter production and organic matter respiration in estuaries. Estuaries, or parts of estuaries, with positive net ecosystem production produce more organic matter than they consume. Think of an agricultural field as a system with very positive net ecosystem production. A system with negative net ecosystem production consumes more organic matter than it produces, and in estuaries this is often because of allochthonous organic matter. Think about a wastewater treatment plant as a system with a very negative net ecosystem production.
Which of the following is considered an indirect trophic interaction?
Predator consumes a grazer and its producer food increases Yes, a trophic cascade is considered a form of indirect trophic interaction.
Pteropods (sea butterflies)
Pteropods are ubiquitous holoplanktonic calcifiers that are particularly important for their role in carbon flux andenergy transfer in pelagic ecosystems.They build shells of aragonite, and contribute 20-42% towards global carbonate production , with higherbiomasses in polar areas as well as on the continental shelves and areas of high productivity, such as areas ofupwelling. For example, along the California Current system, which runs along the Pacific coast of north America,the common pteropod Limacina helicina, can attain high abundances (in high latitudes they can reach hundreds tothousands of individuals per cubic meter) and represents a very important prey group for ecologically andeconomically important fishes, bird and whale diets. This is an example of work conducted by Bernarsek andcolleagues who sampled the abundance and state of Limacina helicina along the California current system, fromAlaska to Baja California, Mexico, sampling several coastal and more open ocean areas. As you can see in the map,near the coast, saturation state of aragonite can be very shallow, due to upwelling. The figure on the right showsthe proportion of individuals that show evidence of shell dissolution as a function of the proportion of water in theupper 100m that is undersaturated. As you can see, the higher the proportion of water that has omega valuesbelow 1, the higher the proportion of individuals that suffer dissolution.5 The pictures on the left show the images of shells of the pteropod Limacina helicina sampled during the cruisefrom the previous slide. You can see they show signs of in situ dissolution.The upper picture is from an onshore station, with the entire shell affected by dissolution, and the picture below isfrom the offshore region, with only the protoconch (that is, the first whorl) affected.These field data also correlate with experimental data. On the picture on the right you can see images of Pteropodsgrown in the laboratory under ambient and high Co2 conditions. You can see that only after 6 days of treatment,there are already clear differences between the shells. The one on the left is healthy. On the one on the right youcan see numerous clear bands, which are areas where the shell is dissolving.Please, watch this short video that shows the shape and swimming capacity of a pteropod raised under ambient pHvs another one raised in acidified conditions.6
Which of these is not an ecosystem service provided by seagrasses?
Reduce coastal water temperatures Yes, seagrasses do not reduce coastal water temperatures.
Seagrasses can help mitigate climate change and its effects. List and describe one mechanism by which seagrasses can mitigate climate change on a global scale and one mechanism by which they can mitigate an effect of climate change on a local scale
Seagrasses can sequester carbon, which decreases atmospheric carbon concentrations and, in turn, directly mitigates climate change. They can also increase pH through CO2 drawdown during photosynthesis, which locally mitigates ocean acidification.
Budget Analyses -Narragansett Bay
Rhode island, medium sized. For their historic analysis they assumed that nutrient inputs from human waste, atmospheric deposition, and agriculture were insignificant. nitrogen sources have increased - no kidding I guess. But the key finding is that the main source of nitrogen to the estuary has switched from the ocean to the land. But sources of nitrogen from land and atmosphere have increased so much that they now overwhelm the ocean sources. Phos the same thing\ ost of the phosphorous entered the estuary from the ocean land now the saem equal. Now most nutrients enter estuaries with freshwater and so they are there at the surface and ready for assimilation by phytoplankton. In the past the nutrients were primarily in the bottom layers so benthic primary producers had first crack at it. o be focused at the salt water end rather than the freshwater end like it is today, because primary production at the freshwater end would have been lower than in at the salt water end, and probably a lot lower than it is today. he percent of total nitrogen inputs that is exported from these estuaries, and they showed that the percent of nitrogen that gets exported CLICK - is negatively related to water residence time. So the longer that inputs of nitrogen cyclearound within an estuary through the stages of nutrient assimilation by primary producers, cycling in estuarine food webs, remineralization by microbial food webs, and exchange with sediments, the more likely it is to be buried in sediments or used for denitrification & anammox and converted to to N2 gas. So here is another powerful way to use these nutrient budgets - to provide predictive tools like this to characterize controls on the ways that elements cycle in estuarine ecosystems.
Trophic guilds
Scavengers or detritivores consume nonliving organic matter• Planktivores consume plankton• Benthivores consume benthos• Piscivores consume fish• Suspension feeders use filters to gather and consume plankton and other suspended particles• Deposit feeders ingest sediments and digest bacteria, algae, protozoa, and detritus Here are examples of organisms that fit these trophic guilds...CLICK - The clam worm Alitta succinea is a deposit feeder - this is the new name for this organismCLICK - The Bay Anchovy is a planktivoreCLICK - Atlantic menhaden are suspension feeders as are oysters and mussels, swimming around with their mouths open and feeding with filter-like gills.CLICK - The blue crab is a benthivore.
forces of change: harvesting
Sea was thick with them, and run aground on them- sea trutles Vessels lost their latitude in hazy weather, could be steered by noise of animals swimming For example, we saw in the wildlife lecture how animals like turtles,dugongs or waterfowl can feed on seagrass. Potentially, seagrass systems may have looked very different in thepast if there were such high abundances of these animals. Or for example, if we are thinking of restoring a system,which should our 'recovered' healthy state should be, what we had 5 years ago? 50 years ago? 200 years ago?
Effects on oil spill fauna
Since petroleumhydrocarbons, and PAHs in particular, are known to induce shrimp mortality in laboratory experiments , theyexpected that they would likely see negative effects on shrimp in the more impacted areas, even though theconcentrations in the field were lower than what is considered lethal in laboratory experiments..17 You can see that the two different species of shrimp exhibit different sensitivity., and while growth rates of brownshrimp are significantly lower in the areas with heavy and moderate oil, there is no effect on white shrimp.Brown shrimp may be particularly susceptible to oil-laden sediments because this species is a prodigious burrowerand, while burrowed, would be in close contact with contaminated sediments. White shrimp burrow less thanbrown shrimp . Unlike many fishes, brown shrimp do not appear to avoid oiled habitat, which also increases theirexposure to oilThis negative non lethal effect suggests that energy is likely used to detoxify (mainly via hepatopancreas) and thuscannot be invested in growth, and as you can see, in the treatments in which food was added, the grey columns,growth was higher than where no food was added (white columns).Although it was not significant, the trends suggest that perhaps under lower food availability, white shrimp maysuffer some negative effect of oil pollution.Interestingly, they did not find differences in infaunal prey biomass in the sediment, which is a commonobservation found when there is oil pollution, so it also suggest that these negative effects of the oil are direct viatoxicity rather than by decreasing the food available.18
Estuarine Food WebsTrophic Transfers
Since real organisms feed at multiple trophic levels, they each end up with fractional trophic levels that make it difficult to model and forecast productivity in an estuary. So for example, if a pelagic fish gets CLICK - half of its energy as trophic level 3 and CLICK - half as trophic level 4, CLICK - then it has a fractional trophic level of 3.5. In order to model food webs, feeding is apportion into integer trophic levels. So that fish with a trophic level of 3.5 contribute half theirfeeding to integer trophic level 3 and half to integer trophic level 4. This is a projection of the same food web with numbers indicating transfers of energy. CLICK - The down symbols represent loss of material to respiration and detritus, CLICK - and the up arrows indicate harvest or yield to humans. Most of the flow is confined to the first 5 trophic levels, CLICK - and it drops off drastically after that. CLICK - You can also see that the trophic transfer efficiencies are much higher between the lower trophic levels. It is 10% for the transfer to herbivores, CLICK - but because many organisms are omnivorous and eat at many trophic levels, the calculation makes the trophic transfer from herbivores to primary carnivores very efficient - close to 50%. And the trophic transfer efficiencies remain high for a couple more trophic levels before they drop off at the highest trophic levelsThis type of food web modeling is good for projecting the most efficient trophic levels for harvesting from an ecosystem, although in general it is most efficient to harvest at the lowest possible trophic level.
Basic food web
So in a basic estuarine food web we have several trophic levels CLICK - including herbivores or primary consumers that consume plants - these are trophic level 2. CLICK - Then there are carnivores or secondary consumers that consume herbivores- like zooplankton consuming ciliates, which are trophic level 3, CLICK - but you can see that the trophic levels quickly become blurred, even in this simple diagram because pelagic fish can be trophic level four CLICK - or they can be trophic level three depending on whether they are consuming invertebrate carnivores or pelagic herbivores. To manage this, organisms are given a fractional or average trophic level depending on the balance of their diet.
Enhanced coastal acidifcation
So we've seen that increases in atmospheric CO2 due to the use of fossil fuels and deforestation have led to anincrease in CO2 in the oceans which has led to acidification and a decrease in saturation states.In addition to this global pattern of water carbonation and acidification, coastal and estuarine are particularlyvulnerable to acidifcaiton because there are other processes taking place that further enhance this process.In this table three main factors are enumerated that can modify acidification of coastal waters, including human-driven eutrophication, freshwater inputs and upwelling.10
Climate-driven range expansions
Species senitive to temp may respond to a warmer climate- moving to cooler location at higher lat or elevation. Limited by colder temperatures, may be able to colonize area that are becoming warmer. Shift in dis of species- more temperature is happening in both marine and terrestial systems, Marine is one magnitured faster then on land- average spread of 20km per year Different rates different species, some slower like benthic algae, mosslusk and larval bony fish Invasive species- aquatic plants and invertbrates reach about 50% Mangrove- increbibly sentive to temperature restricted area, therefor erestricted to lat range- However mangrove warming could actually favor range
Does it balance
Stable nitrogen isotope ratios are a little different because when organisms consume organic nitrogen they tend to fractionate it before making new biomass. So what that means is that organisms tend to use the heavier nitrogen isotopes when making new biomass. CLICK - So with each trophic level the nitrogen isotope ratio in the biomass goes CLICK - up by about 3.5. In theory this can be used to tell you where on the trophic scale an organism lies, and it is cool because it averages out omnivorous feeding at different trophic levels. So if you know the nitrogen isotope ratio of the original food source at trophic level 1, you can estimate the average trophic level of the organism you are interested in. So in this diagram CLICK - these organisms are the primary consumers. CLICK - The euphausids are the secondary consumers, CLICK - and these fish are tertiary consumers - roughly trophic level four The first big test of a food web model is whether it balances -CLICK - do all inputs and outputs from each node balance. This is basic mass balance. In ecopath with ecosim, balance is required for every box in the spatially explicit model. CLICK - The second big test is whether every flux is reasonable. CLICK - The third is whether it matches reality.If the answer is no to any of these questions, then you have to figure out what you got wrong in the model. This can be a lot of work, but it is very worth the effort. These kind of models are what allow us to understand how ecosystem changes associated with climate change and other anthropogenic impacts will influence the food webs of estuarine ecosystems.
Macroalgal invasions are widespread in coastal ecosystems. What makes a successful macroalgal invader? What are the most likely ecosystem impacts of marine invasions of macroalgae?
Successful invaders typically have wide tolerance to variable light, temperature, salinity, and nutrient conditions. They also often have chemical or structural defenses against herbivores and are capable of rapid dispersal and growth. Dense accumulations of invasive macroalgae can cause shading of native algal species and seagrass, declines in fish abundance, diversity, and reproduction, and increased incidence of anoxia and hypoxia.
Ecosystem services
Supporting; which are the services necessary for the production of all other ecosystem services: such as soilformation, nutrient cycling, or primary productionAnd then we have provisioning ecosystem services: such as food, fresh water, fuel, fiber, biochemicals, geneticresourcesRegulating ecosystem services, such as air quality, water quality, purification and regulation, human health, wasteprocessing, , climate regulation, regulation of natural hazards (e.g. floods, fires), pollinationAnd cultural ecosystem services, which include aspects such as cultural diversity, spiritual and religious, recreationand ecotourism, aesthetic, inspirational, educational, sense of place, cultural heritage, knowledge systems, socialrelations3 The idea is that certain ecological processes occur in these ecosystems, providing ecological functions, that can bethought of as ecological production, and this production translated into ecosystem goods and services.
What we call introduced species, which is also often called an alien species, nonnative, exotic, non-indigenous,foreign or adventive, is basically the opposite of a native species
That is, a species that is not native to a region, and it has arrived to this new region with some type of humanassistance (whether deliberate or accidental).4
An excess of organic matter via net autotrophy could have which ecosystem impacts?
The excess organic carbon is exported to adjacent estuaries to support heterotrophy there The excess organic carbon is deposited to underlying deeper waters to support hypoxia The excess organic carbon serves as an organic matter source for heterotrophs, contributing to secondary production Yes, net organic matter production via ecosystem metabolism is a potential subsidy for a wide variety of ecosystem processes.
Budget Analyses - Patuxent River EstuaryLearning outcomes
The exchange with the ocean is calculated as the tidal flux - the volume of water that moves into and out of the estuary - verage concentration of the constituent in the ocean and estuary.These equations show a mass balance, right? The inputs and outputs have to balance, and Pe here is the net production of the constituent, which could be negative or positive depending on the fluxes across the boundaries, and VeCe in the middle is the volume of the estuary times the concentration of a constituent. Then data on water flow are used with these equations to calculate coefficients of exchange of dissolved constituents across boundaries. Then these coefficients are multiplied by nutrient concentrations to calculate the physical transport of nutrients across boundaries and between boxes. Derived coefficients for each box for• Oxygen• Dissolved inorganic nitrogen (nitrate, ammonium)• Dissolved silicaCalculated fluxes across each boundary by multiplying by concentrations that they measured Left in each box was value of Pe net production or consumption of that constitutent
Define fisheries bycatch and describe why it is important to characterize.
The incidental catch of non-target species during fishing activities that is either retained or discarded at sea. Bycatch mortality can be a major source of fishing mortality, particularly for endangered/threatened species. Many estuarine fisheries use non-specific gear that results in high bycatch.
Dave
Then his diet leveled out a 1600 grams of food per day. They fed him mackerel. total nitrogen that dave excreted, which stabilized after about 17 days, andCLICK - total chloride that dave excreted, which stabilized after 17 days and bumped up during an experiment when the researchers added sodium chloride to Dave's food. No water stayed healthie
Give an example of a case where dissolved gas exchange can influence the organisms living in an estuary.
There are many examples where dissolved gas exchange can influence the organisms living in an estuary. One example could be within a hypoxic region. In a hypoxic region, excess nutrients can increase algal productivity, and subsequently enhance microbial degradation of organic matter. The excess microbial activity decreases dissolved oxygen within the estuary, and can result in the death of resident organisms, such as fish. Another example could be through the exchange of CO2 from the atmosphere to estuarine waters. As the CO2 dissolves in water, it lowers the pH of the water, and make it difficult for organisms like oysters, corals, and clams to produce calcium carbonate structures like shells.
Estuarine wetlands can respond to sea-level rise in which of the following ways. (Select all that apply)
They can migrate upland as seas rise. Yes, if there are no barriers, such as dikes, to stand in the way. Correct! Habitat switching Yes, freshwater wetlands may convert to saltwater wetlands and saltwater wetlands may convert to mudflats or open water. Correct! They can accrete at a rate that matches the rate of sea level rise, thus maintaining their position. Yes, but this response is limited by sediment availability.
Estuaries have high numbers of introduced and invasive species in comparison to coastal areas because (check all that apply)
They harbour a high diversity of habitats They have a long history of use by humans Given that species introductions are a result of human activities, areas that have a longer history of human use are likely to have more introduced species than more pristine areas
Estuarine Food Webs
This basic format for food web diagrams comes from the Fundamentals of Ecology textbook by Eugene Odum, which is a very influential textbook for ecologists. Inputs to a food web are circles, which this could be organic matter, nutrients, or light, the bullets are primary producers and the hexagons are consumers.
Ecosystems-2
This figure shows gross primary production per day over respiration per day for a bunch of different systems. CLICK - The diagonal is net ecosystem production equal to zero where the ratio of P to R is 1. So very oligotrophic systems like the tropical ocean and nutrient rich eutrophic systems like fish ponds and coral reefs can have similar net ecosystem production. It is the balance. CLICK - Systems that fall above the line are net autotrophic like algae cultures and some shallow lagoons. CLICK - Systems below the line are net heterotrophic including this blackwater river where respiration is enhanced by terrestrial organic matter and production is limited by the water color. Many estuaries fall below the line because of terrestrial inputs of organic matter and because of export of phytoplankton to the coastal ocean. The blue line with the arrows tells the story of a polluted river, but it is similar to the story of a normal river in which CLICK - there is little production in the headwaters where respiration is supported by allochthonous organic matter from land. This system is net heterotrophic. Then as you move downstream the river gets wider and more sunlit and nutrients recycled by respiration upstream support in-river phytoplankton production, and maybeCLICK - there is a phytoplankton bloom in which production exceeds respiration and the system becomes net autotrophic. But then farther downstream the terrestrial organic matter is used up, and production and respiration get into balance and fall on the line.
Summary Pat
This is a summary of the nitrogen budget for the Patuxent River estuary, determined by integrating across all the seasons that they represented in their box model, and they determined that inputs of nitrogen from the middle estuary, including big productive wetlands that surround the estuary - like in this picture here -, were actually greater than inputs from the river. CLICK - See this 3500 is bigger than the 1940 coming in from the river. A lot of the nitrogen that enters this estuary comes from nitrogen fixing organisms, and from small streams that enter the estuary in this part of the watershed.CLICK - And they also found that denitrification and burial are very large numbers, and accounted for almost half of the nitrogen sinks in this estuary. Without a box model of several boxes they would have missed this dynamic because a lot of the nitrogen flux comes in at the middle estuary and then is buried or denitrified in the middle estuary. So this really demonstrated the power of these box model approaches for describing the element budgets of estuaries.
Pattern of marsh loss parallels
This pattern of marsh loss that was detected experimentally in Plum Island Estuary parallels observations foranthropogenically nutrient-enriched marshes worldwide, with creek-edge and bay-edge marsh evolving intomudflats and wider creeks.This figure shows the global relationship between nutrient loading and salt-marsh distribution and loss.In particular, you can see in the map the spatial distribution of the ramping up of anthropogenic nitrogen loading(dissolved inorganic nutrient (DIN) fluxes) from continents to coastal oceans from the pre-industrial period (1800s)to the contemporary period compared to global locations of salt marshes (thw black dots).For the Long Island Sound estuaries, the figure on the right, shows that there has been a substantial loss of lowmarsh, smaller loss of highmarsh and a steady increase in mudflat area over time, and these changes correlate withincreased nutrients from sewage treatment plants and runoff from land.Thus the authors of this work suggests that current nutrient loading rates to many coastal ecosystems haveoverwhelmed the capacity of marshes to remove nitrogen without deleterious effects.12
Ratio of PN
This ratio is low when nutrient inputs are low and organic carbon inputs are high.
Terms
Trophic = feeding or food• Eutrophic & Oligotrophic• Trophic groups share feeding habits and relationships• Trophic transfers are exchanges between trophic groups• Trophic levels indicate the average number of trophic transfers required for food to reach a group- Primary producers are trophic level 1• Omnivores consume more than one type of food, potentially from different trophic levels
What are two common methods used to study the diest of estuarine organisms? list several advantages and disadvantges to each approach
Two common methods to study the diet of estuarine organisms are analysis of stomach or gut contents and analysis of chemical biomarkers such as stable isotopes. Analysis of gut contents, whether visually or using genomic markers, can provide very specific evidence of what was consumed recently by an organism. The data may be relatively easy to interpret, with the drawback that it is not easy to obtain (labor intensive!) and it may not be possible to determine what an organism's feeding habitats are over a longer period of time. Chemical biomarkers provide evidence of which food sources may be consumed and assimilated into biomass over time. However, interpretation of chemical biomarkers can be complicated and may not resolve the relative importance of different diet components if they have similar chemical composition.
Oil spill terrestrial arthopods
Unique characters of BP deepwater allowed for considerable weathering and degradtion of oil. also offshore However arthopods could recover fast due to migration soil exposed for decades arthos who live in plants less likely to come in contact with oil Impacts of oil spill: Oil regularly reaches sediments after a spillOil in anoxic sediments is persistentOil regularly contaminates Zooplankton and benthic invertebratesFish are also contaminated, but to a lesser extentOil contamination decreases the abundance and diversity of benthic communities.22
feeding behavior/plant defence
When they looked at how this nutrient fertilization may have affected plant traits related to feeding behavior, theyfound that indeed there was an increase in the nitrogen content of leaves, which went from 2.02% to 2.24%, butmore interestingly, there was a huge difference in the content on chemical defenses such as phenols, which wasabout for times lower in the plants that had been fertilized with nutrients.Thus, while grazing may benefit seagrasses under eutrophication by buffering negative effects of epiphyteovergrowth, grazing may also have direct negative effects on seagrass under eutrophication by making seagrassleaves more palatable and nutritious to consumers.11
vectors of introduction
Vector; the transport mechanism by which a arrives is what we call the vector the pathway of intruction is the route between the source region of the non-native species and the location where it arrives sailing in 1800- source of intruducted vectors can be deliberate soruces of introduction Main vector; aquaculture- import species from other areas that want to grow for consumption- japanese oyster escap example same with atlantic salamon - competiotion with native species and disease and parasite transfer
How are increased global temperatures, combined with an enhanced hydrologic cycle, forecast to impact phytoplankton community structure and function? (Select all that apply)
Warming will favor cyanobacteria production. Changes to freshwater and nutrient inputs will alter productivity. Yes, changes to the magnitude and seasonal patterns of freshwater and nutrient inputs are forecast to alter patterns in phytoplankton productivity. You Answered Changes to estuarine residence times will alter community composition. Yes, changes to estuarine residence times are forecast to favor different taxonomic groups of phytoplankton.
Explain how gas exchange between the atmosphere and estuarine water can change the pH of water.
When atmospheric CO2 dissolves in water, it forms carbonic acid (H2CO3). Carbonic acid then forms a bicarbonate (HCO3-) and a hydrogen ion (H+), which decreases the pH (i.e., increases the acidity) of the water.
The distribution of mangrove wetlands vs salt marsh wetlands in the intertidal zone around the world is determined by which of the following conditions:
Where the duration/severity of freezing temperature is frequent, mangrove wetlands are replaced by salt marsh vegetation, which correlates well near the 16°C isotherm for the air temperature of the coldest month.
What is a food web and how does it differ from a food chain
Whereas a food chain refers to a linear series of trophic transfers from one group to another, a food web describes a network of trophic transfers. There are several important differences. A food chain has a single trophic pathway whose length and number of integer trophic levels is determined by the number of trophic transfers in the chain. In contrast, there can be many different trophic pathways in a food web and these can differ in their length and number of trophic steps. Depending on the structure of the food web, organisms in a single group can feed at more than one trophic level, resulting in fractional trophic levels (often termed 'trophic positions').
Warming: different negative effects
While warming may have negative effects on species, one may expect that species with wide distribution rangesmay respond differently to global warming depending on where they are growing at, as they could have differentadaptations to local conditions that have made them more competitive in that latitudinal range where they live.For the species that live at the more tropical edge of the distribution one could hypothesize that they may be moresusceptible to a change in temperature if they are already close to their limit. However, these populations may bemore adapted to warmer conditions and thus perhaps could better resist warming. In experient- all three populations suffered decrease in yield in response to heat wave, each different in response during recovery. Northern- yielf of photo decreased, even though was back to natural levels southern- similar normal activity- or non-effected plants Suggest- Lower lat are better adapted to warmer temperatures- thus appear to be more resilient to warming stess, hypothesize that because it is closer their limited distribution range of the species, closer to thermal tolerance level- May have locally adapted Heatwave ches- absent- lower range was not able to withstand. Therefore different plants different responses.
Esturaies are highly invaded systems
Why do we care about species invasions in this class? Well, because estuaries are some of the systems that harbor most numbers ofintroduced and invasive species in the world.You can see in this figure, for example, the number of introduced invertebrates in different coastal and estuarine areas of the world. Andyou can see that, for many of the areas studied, number of introduced species in estuaries (white columns) are double to more than 7 timeshigher than for the coastal areas. The high numbers of introduced species found in estuaries can be a result of several factors:It could just be that because they are areas that we use often and they are relatively easy to sample, so we can study them more and so ahigher sampling effort implies that we detect more species.However, other factors are likely contributing to higher abundances of non-natives found in estuaries.In relation to human activities, estuaries have historically been areas of human settlement. This means that human presence has been largefor a long time in these areas and since introduced species arrive through human activities, estuaries can become hotspots of introductions.The are also environmental factors that are likely contributing to the high numbers of introduced species in estuaries.For example, estuaries harbor a high diversity of habitats; freshwater / brackish / marine), soft sediments, hard substrates, vegetated areas,etc..... This high diversity of habitats likely provides more opportunities for a new species to settle,In addition, since estuaries are often harsh environments, they tend to have lower numbers of native species, decreasing the probability ofcompetition with natives, and also if the new species is a strong competitor, a native species that is surviving in a harsh environment may beeasier to outcompete. Finally, estuaries are often relatively closed systems (since water circulation is limited), which also favors theestablishment of species which may be washed out otherwise in the open coast.8
eutrophication state in US estuaries
You can see that the east and the Gulf coasts of the US has the most impacted estuaries in terms of eutrophication,whereas on the west coast we have more greens and blues but also whites, so there is still not a good knowledge ofeutrophication impacts on the west coast.In addition, many of the estuaries studied have not changed their status since they were studied 10 years before,and reports of improvements or further degradation are not dominant.So you can see that eutrophication is a widespread problem along US estuaries. And, indeed, this loss of seagrass has been associated with this increase in nutrients. The figures on the right showthe changes in abundance of seagrass, macroalgae and phytoplankton (here measures as chla (, and you can seethat with increasing N loads there has been a steady increase in chla and macroalgae and a steady loss of seagrass.These nutrients have enhanced the abundance of macroalgae and phytoplankton, which has been able tooutcompete seagrass for light.6
What are natives
a native species, also often called indigenous,A species is native to a region if it evolved there, or if it evolved elsewhere but arrived in the region by its own means(usually thousands or millions of years ago) through range expansion and without the intentional or accidentalintervention of humans
Container incubations
advantages• Gives you partitioned Rnand Pa• Can experiment (light, nutrients, temp, OM, etc.)• Disadvantages• spatial variability difficult to sample• Bottle effects• Cannot measure all components• Grasses? Benthic respiration These incubation measurements are very powerful because they allow you to partition nighttime respiration and apparent daytime production. They also allow you to mess with the system and experiment with different light levels, nutrient levels, temperature, organic matter, etc. So for example, this is one way to run nutrient limitation experiments. You can add nitrate or phosphate to these incubations and see if they increase production. If the community is not nutrient limited, then production will not increase.CLICK - The disadvantages of this approach are that spatial variability is difficult to sample, so you have to make a lot of measurements. Second, there is the everpresent problem of bottle effects - bottles are different environments than nature, and the organisms can react to that. They grow on the walls, they react to changes in dissolved oxygen, and the simple process of collecting water and putting it in a bottle jostles the organisms, breaks up particles, and just messes with the system. Third, we cannot measure all components of the system in these bottles. What do we do with seagrass production and benthic respiration? Other method The other method is to just measure oxygen in the water continuously during the day and night. So imagine putting an oxygen sensor in the water above a seagrass bed.CLICK - The way this works is that during the day oxygen increases because there is more production than there is respiration, and then at night the opposite happens. So the sum of oxygen flux during the day is apparent or net daytime production Pa, and the sum of oxygen flux at night is nighttime respiration RnCLICK - and it turns out that that equals gross primary production for the whole day minus respiration for the whole day, with one key assumption... That respiration during the night is the same as respiration during the day.
Deliberate introduction
aquarium/ornamental species trade freshwater and marine Most invasice released from an aquairum is green alga-killer algae Nutria- fur farming - no longer revune, freed them into the wild Management- erosion control- introduced in coastal wetalands for erosion control because their dense stem and thick roots and rhizomes. filter and sediment particles Shipping activities- ships use water, soil and rocks for ballast on ons eide and discharged expledded many species can be introduced this way This foulingcommunities and be complex and actually harbor mobile species that inhabit this new community and thus can alsotake a ride to a new environments. canals vectors of transport- enable organism transport between waters they connect- overcome biogeographic allow migrate to water which they were isolated from Suez canal red sea and the Mediterranean sea Arrived along side aquaculture Tsunami drift- accidental introduction like as tsunami debris 104 non native species due to docks being washed ashore
Current atmospheric carbon dioxide concentrations (Select all that apply)
are causing the earth to warm faster than it has in the past 800,000 years. Yes, according to the IPCC, observed increases in atmospheric carbon dioxide concentrations are directly related to observed increases in temperature. exceeds 400 ppm Yes, atmospheric carbon dioxide concentration first exceeded 400 ppm in 2015. are as low as they ever will be in the next 100 years, under the IPCC RCP 8.5 scenario. Yes, the RCP 8.5 is a "worst-case" scenario where carbon dioxide concentration increases to 950 ppm by 2100.
Importance of different vectors
ballast normall requarded as most imporatn vector of aquatic non-native species shipping in veneral is the most prevalent vector aquarium released is the second most important vector aquaculture and shellfish farming also important vector Aquatic invertebrates in US is predominant, 20-30 vector is unknown but it is critical to know for adequate management- successful eradiation is rarely possible stil
Warming effects on hypoxia
by increasing water stratification and thus reducing mixing and ventilation of waters,by modifying ocean circulation patterns that could promote low oxygen waters (e.g. upwelling brings deepwater that is rich in CO2 and lower in Oxygen) .By decreasing oxygen solubility and by increasing respiration rates of organisms (and thus higher use ofoxygen) when enhancing metabolic requirements. mediam lethal concen increaded on average of 16% in warmer water They observed that overall, SURVIVAL UdNER HYPOXIA IS REDUCED, ON AVERAGE 74%SO again, NEGATIVE DIRECT EFFECTS OF HYPOXIA (LOW OXYGEN) MAY BE AGGRAVATED under warmingconditions.13
macroscopic species- bivales
complex life cycle,larvae living in the water column and juveniles settling onto the benthos. metamorphosis is strongly affected by larval exposure to elevated pc02 condtions. 11% size at meta for individuals reares at high pc02 that those in control survial much lower also Therefore, the conditions under which larvae grow have important carry over effects to the next life stage and thus canhave long-term effects for the populations.7 hatchery oyster issues hey realized that they were having many events of high pCO2, low pH, and they were able todetect that larval production was greatly affected by omega value of the water. So ocean acidification was having a8 negative effect on the larvae and thus greatly affecting the hatchery production.In the figure on the left you can see changes through time on many paratmetere at the estuary. On the top you can seechanges in salinity and temperature through time during the spring and summer of 2009 (from approximately May toAugust), which is the typical time when we see upwelling on the PNW. This time period is also when oysters arereproductive and produce the larvae that the hatchery wants to rear and sell. You can see that during this time period,there are some peaks when pH and saturation state largely decrease, and it coincides with this strong upwelling events, asit is correlated with the arrival of this cold, deep, carbon rich watersIF we look at the figure on the right, we see that the production of larvae at the hatchery is negative at omega valueslower than 1.7. Remember that we mentioned previously, that typically it is considered that omega values below 1 implyshell dissolution and above 1 imply calcification, but clearly the pacific oyster larvae need omega values much higher than1 in order to be able to grow and survive. If you look at the figure on the left, you see that there are many time periodsduring the spring summer of 2009 when omega is below 1.7. addition to the direct negative effects that bivalves such as oysters may suffer from OA, which decreases theircapacity to form shells, these organisms may additionally suffer from indirect effects. For instance, Sanford andcolleagues tested whether ocean acidification modifies the susceptibility of native Olympia oysters to predation byan invasive snails, Urosalpinx cinerea, which is the Atlantic oyster drill.As you can see on the figures on the left, which show the size of the oysters and the number of oysters eaten fromthe ambient CO2 treatment (in black) versus the high CO2 treatment (in gray), oysters raised under elevated pCO2were smaller in size and experienced a 20 percent increase in drilling predation than oysters raised at present CO2conditions.In addition, the snails were actually tolerant of elevated CO2 and did not experience any change in their feedingbehavior.Indeed, as you can see on the figure on the right. When snails were offered a choice between the two types ofoysters, they strongly preferred oysters raised under high CO2 levels, whether the snails were eating at ambientCO2 or at high CO2.As you can see in the figure, neither the preference nor the total amount of oysters drilled changed with the waterconditions in which the experiments were conducted.10
N Isotope fractionation
d15N‰ = [(15N/14N)sample / (15N/14N) standard - 1] x 1,000• Thought to occur during amino acid synthesis and mineralization• Heavier isotopes (15N) are preferentially retained because they form bonds of greater energy, and are less likely to undergo chemical reactions• Lighter isotopes (14N) are preferentially lost when amino acids are altered (transamination) and mineralized (deamination) Nitrogen isotopes are different than carbon and sulfur isotopes because they are fractionated as they pass from one organism to the next. CLICK - this is thought to happen during amino acid synthesisCLICK - What happens is heavier isotopes form bonds of greater energy, and so are less likely to undergo chemical reactions, and so tend to get retained in biomass.CLICK - Lighter isotopes are favored for mineralization reactions because they form bonds that are easier to break and reform. So these are preferentially lost. The result is that organisms get heavier in N-15 isotopes as nitrogen moves up trophic levels.
Saturation state
difficult for an organism to build their skeleton, product of calcium and carbonate ion conc, dependents on ks. the apparent solubility, depends on temp sal pressure and the particulare, mineral phase when omega below 1, skeletons made of calcium carbonate are dissolving, above 1 calcification can take place. Argonite and calcite, arg is 50% higher solubility then calcitee Solubility higher at lower temperatures and higher pressures. As you can see, aragonite, being more soluble, has an omega of 1 in shallower waters than calcite, becausesaturation decreases with pressure and temperature, which are typically higher in deeper waters.8 Doney et al. 2009Observed changes in W: decreasingIn this figure we see that in a similar fashion to what we observed for a decrease in carbonate, omega for botharagonite and calcite have been decreasing during the last twenty years approximately, since monitoring of theseparameters started taking place in the surface waters of Hawaii, at the ALOHA station.
Sea otter trophic cascade
e otters predate on crabs, which allows for thepopulatiosn of mesograxers to recoer, and they can feed on the piphytes and, in this way, buffer the negativeimpacts of algal growth on seagrass.5
Scheldt estuary in the Netherlands by Antwerp.
eatern and western This graph shows both measurements and model estimates of gross primary production Pg and net ecosystem production Pn along the salinity gradient of the estuary. These are pretty high rates of gross primary production - between 25 and 50 mmol carbon per meter squared per day CLICK - for both 1994 in blue dots and CLICK - 2003 on the green line, and in fact Pg use to be much higher than this before a massive upgrade to the wastewater treatment plants cut the supply of nitrogen to the estuary. This is a highly eutrophied estuary where you would expect a ton of primary production causing it to be net autotrophicCLICK - but measured and modeled net ecosystem production says the system is actually net heterotrophic at all salinities, and particularly at low salinities, and this is because when they upgraded their sewage treatment plants they did not cut off the massive supply of organic matter to the estuary, so respiration remains very high, causing the estuary to have a very negative net ecosystem production. I think it is possible that it was once net positive, but secondary wastewater treatment changed that.
ecosystem effects invasive
ecossystem enginers Spartina make very successful invading mudflats, become nw ecosystem, densely vegation mat large amount of aboveground biomass produced by invasive trapping sediment, modifying the geomorpholoy of the land change in density and diversity of infanual , resulting from reduction of avaiblity of belowground habitat, from changes in food supply from changes in predation pressure, as well as changes in water and sediment chemistries comb jelly-ballast water
economical benefits of invasive species
european honey bee apis mellifera, pollinator 14.8 billion atlatnic salmon-
trophic cascades
from otters to predatory crabs, tosmall grazers, to algal epiphytes, to seagrass increase in otters recovery of eelgrass, correlation between otter and seagrass abundance trophic; otters ate the crabs that would otherwise feed on mesograzers, thus the high abundance of mesograzer decrease the abundance of epiphytes which would otherwise limite seagrass abundance, favoriing the seagras When there was high abundance of otters, there was much higher abundance of these small mesograzers (becausepredatory crabs were not abundant as they were being eaten by the otters).In addition, these changes in mesograzer abundance due to presence or absence of otters, translated into strongdifferences in algal epiphyte abundance on the seagrassAnd this changes in epiphyte abundance lead to important differences in seagrass abundance.Indeed, where otters are present, seagrass abundance is nearly double than where otters are absent, as grazers arethen highly consumed by crabs, which leads to much higher epiphyte loads that impact the seagrass. However, since nutrient additions are going to change plant traits, this may also modify grazing on the plants., andthis is related to the fact that Plants have different traits that they have evolved to resist consumption. These includenutritional and chemical traits. For example, a lower nutrient content will make a plant less nutritional and thuspotentially less attractive to herbivores. Indeed, seagrasses have a high Carbon to Nitrogen ratio, which means thatcompared to other primary producers such as algae and plankton they are less nutritious and typically lesspreferred. In addition to nutritional quality, plants also often have chemical defenses that make them less palatableor even toxic to consumers. There are many types of chemical defenses, but phenolic acids have been commonlydescribed in algae and plants as defense compounds against herbivores.
Always negative?
habitat formins ecosystem enginers, australian pines in florida beaches- increase habitat suitablity of nesting loggerhead sea turtles by reducing the light that reaches the beaches from nearby urban areas provide additional habitat or food- eelgrass beds invaded high abundances of the introduced red alga- tended to support higher abundance of invertebrrares particularly juvenile states of inviduals also gastropods and bivales making new habitat- attracting new species
seagrass loss
hat show how the loss of seagrass habitat loss leads to the loss ofother species which can be very important ecologically and economically for example, in terms of fisheries, such asscallops or fish. the figure on the left shows differences in fish diversity and abundance in different estuaries and howit relates to seagrass; white columns represent data from where seagrass is absent, grey columns representintermediate values of seagrass density, and black columns represent values where seagrass is abundant. Clearly,values of abundance and richness strongly decrease as seagrass abundance decreases.The figure on the right shows the catches of scallop in Waquioit Bay, for which remember we saw a major loss ofseagrass. Here you can see that, especially at one site, scallop abundance has been steadily decreasing along thesame time that seagrass has been decreasing.So this eutrophication causes a severe loss of seagrass that also translates into the loss of ecologically andeconomically important species.8
changes in sedimentation pattersn
hese changes insedimentation can be very important, further modifying survival of plants by changing burial and erosion rates,causing smothering and also changing light availability by causing turbidity.9 Plant surival, imprantance of connectivity among plants- resist negativ eeffects colonal integration is critical in determinignt the capcity of plants to resit negative effects of buriral When connectivity is broken negative results- when connectivity amongst them is broken clonal connection survial to burial may not occur in burial is very high or large in space- internal transport is spatially limited and if buriral is long term, subsidies from neighbors not enough
Seagrass populations affected?
higher abundance of herbvorous fish translates to increase consumption rates of seagrass. nearly 60% net annual primary producitivity cna be consumed instide mpa harbivores also can change strucutre of canopy)Abundance and size of plant )- cascasding effects for species that use seagrassa as habitats for food or shelter Mpa's can be a double-edged sword
Metabloc rates
linked to temperature, changes in temperature can have effects on individuals in their physiology, growth and reproductive patterns and survival. individual level translate into population effects determine the abundance and distribution of species also interact with other species- with each other as it may change themetabolic requirements, dispersion capacity, etc. of different species in a different manner.3
Chesapeake Bay
his is an organic carbon budget for the chesapeake bay to give you an impression of the important fluxes. Inputs of organic carbon from land and the atmosphere and vascular plants are pretty small compared to CLICK - autochthonous production by algae. Input from the susquehanna R. is locally important in the upper bay, but phytoplankton really rule. Some is exported to the ocean and some is buried. Some is caught with fishing gear, CLICK - but most of it is respired to CO2 in the plankton or in the sediments. This shows average measurements of production and respiration in three regions of the Bay over a three year period.CLICK - In the Upper Bay, inputs of organic matter from the susquehanna river keep the region net heterotrophic. CLICK - Middle Bay the system is mostly balanced over the year, with both production and respiration highest in summer and lowest in winterCLICK - The Lower Bay is net autotrophic for a lot of the spring and summer because of the relatively clear water and the shorter residence time as the newly produced phytoplankton production flows out to the ocean.Note that the lower bay goes heterotrophic at two times during the year. The first follows the massive spring phytoplankton bloom and is caused by the respiration of all that new production. The second is at the end of the season when primary production becomes very low, but there is still plenty of organic matter around to support respiration.
So what happens if the ecotrophic efficiency of pelagic herbivores is 0% and all their biomass goes to detritus?
his would include planktivorous organisms like anchovy and oysters. All the plant and herbivore production would go to detritus and to bacteria. If we assume a trophic transfer efficiency of 10%, this food web becomes rather inefficient at producing larger organisms that humans can harvest. The transfer from trophic level 5 to 6 shrinks by a factor of 5. For example, the american silver perch eats other fish, but it also eats macro and microbenthos, zooplankton, a little plant material, and detritusCLICK - The other point is that a lot of consumers appear to include detritus in their diets, including many of the larger secondary consumers that east mostly fish.
Genetic impacts of invasive eco level
hybridization impact on gnetic level- reproduce with native species and hybridize Direct negative effects on loss of native genetic pools is the hybrid are sterlie- gamates are wasted able to reproduce? may compete with parent species example smooth cordgass-spartina lterniflora native from the eastern coast of NA for erosion control and saltmarsh reclamation as well as aquaculture- hybrized with california cordgrass produce different ypes of hybrids, depending on proportion of genetic material they have from each of the parental species Super hybrids- more vigorous than their parents and are able to outcompete them fifty precent or more of invasive genetic material veyr high biomass, those with seventy and ninety percent of invaisvgenetic material more fit than either of the parents- o and a hundred super hybrids withstand broader ranges of salinity either in the parent species, may give them further competive advantages to colonize areas some even have the ability to self-fertilize- increases their ability to spread
Carbonate chemistry
increase in c02 levels change in ph and the abundance of carbonate ions- ocean acidification
increase in introduction of nonnative species
increase in studying efforts, increase in trades
physical level population
invasions of red alga- native seagrass can hamper water exchange, light penetration nec for photosynthesis, some cases physically obstructing new levels to grow upwards seagrass in terms of length of leavea as well as biomass- causing high mort
Diamondback terrapin
is a species of turtle native to the brackish coastal tidal marshes of the eastern and southern United States, and inBermuda, which it was traditionally used locally as a meat source by the local communitiesIn the 19th century, however, it started being exported as a delicatessen to be sold to restaurants fell out of flavor no longer wanted therefore harvesting no more
oil spill
its CHEMICAL COMPOSITION, andthis will be largely driven by the type of oil and the weathering.When the oil spills, it undergoes changes due to weathering (evaporation, dissolution, emulsification,sedimentation, microbial oxidation and photooxidation).- There are main 4 classes of Hydrocarbons in crude oil , which are SATURATES, AROMATICS, ASPHALTENES, andRESINS.- The polyAROMATIC compounds have a structure that make them highly soluble, and thus can be easilyincorporated into the biota and create problems. In addition to this weathering process determined by the environmental conditions, microbes play a critical roleand in fact MICROBIAL DEGRADATION IS THE MAIN BIOLOGICAL PROCESS BY WHICH oil is degraded in wetlands8 Impact: Depend on type of spill, type of plant and other environmental factors therefore if spill in winter when plant metabolism is slower or plants are domrant- effects lower then in spring/summer Different crudes different effects.
oil spill 2 response of wetland plants
low toxicity if already oil weathered= but coating plant can cause negative effects by preventing photosyntehsis,eca. etc IF OIL PENETRATES into soil and comes into contact with nut absorbing roots and shoot-generating rhizomes oil DEGRAdes slower in anoxic environments, also perpetuated for longer periods CLEANUP strategy- manual removal can cause more harm them good 70 or more % on stem oiled-low surviorship 50$ or less much higher proption of live plant- survive certain amount of oiling 40-0 hardly any 80 coverrage had more then 60 mort And recovery of surviorship goodnews- salt marsh less then 2 years. But oil driven plant death at edges more than double shoreline erosion further driving marsh platform loss
co2- climate mangrove
mangrove c3 plants, more leaf area and overall more biomass, change in chemistry. Under high co2 had lower nitrogen content and, incorporated more carbon. Dilution effect cause they using a lot of nit to grow so they could incorpm more carbon, few months, and many didnt appear to 8 months.
genetic impacts on individual levels
modifying behavior - new species predator native species- prey which negatively impacts their capacity to feed modify vital rates of indivudals such as growth or reproductionn native sea urchins reduced when they feed ont he invasive alga- when they feed on native via competion introduced snail batillaria attramentaria succesfully invaded mudflats in north cali very strong decline of the pop of native mud snail cerithidea overlap in niches- deeding on diatoms introduced snail more efficient at converting limited resource to grow At population level inavisve crab comp, decreased in pop of shore crab, in west coast
community impacts
negative effects on abundance and community structure of macroalgael
Predicting Pn
norganic nutrient flux• Controls Pa (along with light)• e.g., nitrate and ammonium input to an estuary from rivers and coastal ocean.• Organic matter flux• Influences R (makes it higher)• e.g., terrestrial organic matter and river phytoplankton, coastal phytoplankton from ocean Net ecosystem production in estuaries CLICK - is definitely influenced by inputs of inorganic nutrients from river and ocean. CLICK - This is a major factor controlling net daytime production, along with light. CLICK - For example the rate at which new nitrogen flows into an estuary generally correlated with the rate of primary production. CLICK - Net ecosystem production in estuaries is also influenced by organic matter inputs CLICK - which provide extra material for microbes to respire. CLICK - This could include terrestrial organic matter and river phytoplankton, coastal ocean phytoplankton, and probably dozens of other potential sources.
Crustaceans co2
o, if the variable that we are looking at, for example, survival, is the same under thecontrol and the acidified treatment, that means that the ratio of those values is 1, and thus the log is 0. So, if theconfidence interval includes the value 0, it means there is no effect of OA on that process. On the contrary , if theresponse of the variable (for example calcification), is smaller under OA conditions, it means that the ratio is goingto be less than 1, and thus the log of that ratio will be a negative number. In this case, what we are seeing here isthat for the 4 variables examined, survival, calcification growht and reproduction, there are significant negatvieeffects of OA, as the overall mean values are negative and their CI do not include 0.7 Not all species respond equally. Crustaceans respond pos- crust able to maintain a high control of intracellular ph through ion-transport regulation and thus may be able to maintain able to optimize environmental cond. Most ecoskelton of crust covered in biogenic covering- buffer their caco2 structure from direct diss in acid seawater. urthermore, crustaceans moult their shells regularly and have less CaCO3 in their structures and this is in the formof calcite rather than aragonite (which is more soluble). Similarly, OA appears to mainly affect growth negatively incalcareous algae and corals but not echinoderms or other groups. In general, different types of organisms may havedifferent physiological mechanisms to deal with changes in pH (e.g. proton and calcium pumps, development ofprotective membranes, changes in metabolic rates... ), which may explain in part some of the differences inresponses that we see. We also see variations in other types of responses. For example OA seems to negativelyaffect growth of corals and calcareous algae but not in equinoderms or other groups
List three ways in which climate change will likely impact estuarine aquaculture.
ptions include: shifts in species suitable to culture in a given estuary, shifts in abundance and catch of species harvested in a given estuary, higher disease in some areas, increased turbidity due to sea level rise, changes in salinity/DO/circulation patterns, ocean acidification.
economic impact from invasive
public health negative, diseases as well as recreation paralytic shellfish poisoning puffer fish. This was a fish that was introduced to the Mediterraneanfrom the Red Sea, and it bio-concentrates Tetrodotoxin, which is a very potent poison which causes muscle paralysis,and can lead to respiratory arrest. As an example of how an invasive species can have negative aesthetic impacts anddeteriorate recreational activities, I am showing you here the alga Codium fragile subsp. Tomentosoides the so called"dead man's fingers" , it can accumulate in beaches, for example in MA, and it causes negative effects because itsrotting branches on beaches cause very offensive septic-smelling through the release of methane gas.12 more species known to cause economical than ecological damage green crab- aquatic weed
Tomales bay
s a small techtonic estuary on the coast of californiaCLICK - that lies right on top of the san andreas fault line. It has a small watershed and is fairly pristine with very little human impact. alculated gross primary production from their measurements of apparent daily primary production using a correction factor, and they found that most of the production in the estuary is done by phytoplankton, but benthic algae and seagrasses are also very important. This is gross primary production and total respiration measured continuously over 9 years, CLICK - and you can see the seasonal shifts in gross primary production here. Respiration follows the same seasonal pattern, CLICK - but a lot of that respiration is benthic. CLICK - So a lot of the planktonic production gets consumed and respired in the sediments after sinking or after being gathered by filter feeders. And the balance between the two - which they express as net ecosystem respiration s positive all the time with more respiration than production, but varies quite a bit, CLICK and this research group discovered that it varies with the upwelling index on the coast. When upwelling was stronger net ecosystem respiration was higher. Why do you think that is? What does upwelling provide? IT turns out that in years with a lot of upwelling there is a lot of phytoplankton production on the coast, and that phytoplankton gets into tomales bay and boosts respiration and increases net ecosystem respiration. So that is consistent with what we have been talking about. Allochthonous inputs of organic matter boost respiration and decreases net ecosystem production.
invasive
scientists- invasive is an introduced species that sustains self-replacing populations over several life cycles, often in large number at consdierable distances from parents. and or site Managers Us fed regulation executive order 13112 invasive species means and alien species who introduction does or is likely to cause economic of environmental harm or harm to human wealth IUCN introduced species that generates a negative impact on the local ecosystem and species
tropical example of habitat
sea turtle abundance overtime- 20 individuals per hectares- highest sea trutle density every reported- Sea turtles mow the seagrass however here in this habitat they dig in the habitat to remove seagrass and ate rhizomes of plant- stores sugars and starch therefore more nutritious food source therefore turtles destroy seagrass completely leaving gaps- and cant regrow hisemphasizes the need for policy and management approaches that consider the interactions of protected specieswith their habitat. nd so this brings back again the idea of shifting baselines, and how we are protecting areas inorder to somehow bring back ecosystems to a 'pristine state' as they were in the past, and then we encounterunforeseen consequences.
Seagrass and climate change
seagrass may benefit from inrease in c02 levels, photo under higher co2 levels, was between 1.5- 3 times higher under ambient co2 conditions This is a tropical area where there are herbivorous fish, including rabbitfish of the genus Siganus, which you can seein this picture.Interestingly, the authors found that seagrass from the acidified area was more consumed than the seagrassgrowing under ambient CO2 levels.As you can see in the figure, consumption of ambient seagrass is about three times lower than consumption of theseagrass growing under high CO2 The authors found that the content of different phenolic compoundssuch as gallic acid, tannins and folin phenolics, were much lower in the plants growing under high CO2 levels (thewhite columns) in comparison to the plants growing under ambient CO2 (black columns). Thus, the higher CO2availability changes the carbon metabolism of the plants, and in this case it also changes the production ofchemical defense. And this phenomenon is even more interesting because the evidence from terrestrial plants isthat when there is an increase in CO2 availability in the atmosphere, plants actually produce more of thesephenolic compounds (which are carbon-based) and thus become less palatable to consumers, which is theopposite of what we see in this example with seagrasses. So, even though seagrasses could benefit from increasedCO2, as it would enhance their productivity, this work here suggests that they may also suffer higher herbivorypressure, which may counteract or even have overall negative effects on seagrass productivity and abundance. Theresearch on this topic is still relatively new, so there are not that many studies that have considered the effects on11 ncreased CO2 on seagrass herbivory, and we will have to wait a few more years to see if the case that we have seen forQueensland is generalizable to other species and other areas, to assess if there are any overall patterns, and what thelong-term consequences are (e.g. if the balance between increased production is overwhelmed by increased grazing).11
temporal vector trens
ship and ballast increasing over time steadily increase via oyster aqua also(acce in 10 species in 20 years_ fouling increases inearly
Net Ecosystem Production
summation of anabolic and catabolic processes- Anabolic - use energy to synthesize organic matter- photoautotrophy, chemolithoautotrophy- Catabolic - derive biochemical energy from OM decomposition- aerobic and anaerobic respiration• Includes import and export of organic matter• Production stimulated by light and nutrients• Respiration stimulated by temperature and labile organic matter Net ecosystem production is the summation of the anabolic and catabolic processes in an ecosystem. CLICK - Anabolism is carbon fixation and production of new biomass. This is done by photoautotrophs - both the oxygenic types like diatoms and cyanobacteria and seagrass and marsh plants, and the anoxygenic types like purple sulfur bacteria. Anabolic processes are also carried out by chemolithoautotrophs like the nitrifiers and sulfur oxidizers.CLICK - Catabolism is the process of deriving energy from organic matter decomposition. This is done by everyone - heterotrophs respire organic matter for sure, but autotrophs also respire - they create organic carbon that they respire if they need to. CLICK - In ecosystems, calculations of net ecosystem production has to include import and export of organic matter, so advection matters, and I'll explain that in detail.There are lots of controls on Net Ecosystem Production and I'm hoping to break those down for you in this lecture, but at the core, CLICK - production is mainly stimulated by light and nutrients, and CLICK - respiration is stimulated by temperature and lablie organic matter. So these things are not at all independent, right? Production produces the organic matter that matters for respiration, and respiration recycles nutrients that matter for production. So these things are connected.
Marsh alteration and Destruction
the conversion of marshland to upland was undertaken for agriculturalpurposes, but in the past century it has mainly occurred for urban development. construction of storm surge barriers- keep floodwaters of reclaimed marshaldn that has subsdided belwo- and build on it Harvesting of salt marsh hey 67% loss worldiwde wetland Habitat loss is also a big problem in tropical areas. Indeed, a review performed in 2001 showed that in the last 20years at least 35% of mangrove forests have been lost, and these are rates that are higher than the loss of tropicalrainforests or coral reefs.6 he most important human activities that are causing the degradation and disappearance of mangrove forests arethe conversion to create shrimp culture farms and forestry use.7
For the first ten years of the 21st century, the largest fraction of the observed increase in ESLR was due to
the thermal expansion of sea water as the earth and ocean warms.
Warming
warming is occuring in oceans. Regional difference in warming. Not only on sea surface but below as well top 2,000 meters
C02- climate change
we think c02 may favour primary producers that use c02, by increasing substratee, consequently increasing the carbon fixation rates. C. Metabolism driven in effect c4 plants are more efficent at using c02, concentrate co2 in chambers in leaves c3 plants do not have that, co2 directly. from air. Therefore the c4 is alrdy capturing co2 efficently, so not responding increase in co 2 conc in atmosphere Most plants in the world are c3 plants, and these changes in co2 in atmosphere, can have consequences in marshes, may change comp of marshes if c3 plants become more competive as a result of this increase in co2
Budget Analyses case studyGreat Sippewissett Marsh
western shore of Cape Cod he dominant bivalve in this system is the ribbed mussel. The question in this case study was what is the role of filter feeding bivalves in the nitrogen budget of this salt marsh ecosystem? much of the nitrogen they consume through filtration CLICK - is deposited in fecal pellets, - a small amount is committed to growth of bodies and gametes, and the rest - is excreted or used in producing byssal threads for attachment. The model made it clear that fluxes due to dissolved organic nitrogen exchange, mortality, and recruitment were so small scale that they were unimportant in the budget N exchange in the ecosystem seem to be dominated by CLICK - resuspension and sedimentation between the water and the sediments, but CLICK - the magnitude of filtration by mussels account for a large fraction of the difference in this exchange, and long-term burial of nitrogen balances the budget significant contributor to the exchange of materials between sediment and water in this estuary, capturing nearly 10% of the resuspended nitrogen in the estuary, and depositing about half of that material back into the sediments. Here they created a budget for mussels and nested it into an ecosystem box model of the water column, marshwater and sediments, but you could do this for any organism you are interested in.
Plum Island Sound
which is a salt marsh estuary in northern Massachusetts. Measurements of marsh-atmosphere CO2exchange made using chambers indicate the extensive tidal wetlands in the Plum Island system are strongly autotrophic and exhibit a seasonal pattern of carbon uptake from the atmosphere during the growing season (June through October) and moderate carbon loss to the atmosphere in other months. The production of organic matter in tidal marshes is the key process driving carbon sequestration in coastal marsh ecosystems. While much of the carbon fixed into organic matter by GPP is respired by plants and heterotrophs, NEE on an annual basis reflects the net uptake balance of CO2from the atmosphere During marsh flooding, the vertical marsh-atmosphere exchange of carbon is attenuated.). Changes in vertical exchange may reflect actual changes in rates of metabolism; for instance, GPP becomes limited by availability of CO2when plants are submerged, and turbid waters reduce the light available to fuel photosynthesis (Vervuren et al. 2003). However, metabolites may be exchanged directly between the marsh and the flood water, instead of the atmosphere, resulting in an apparent decline in metabolic rate as measured by chambers (Fig. 14.10) and eddy covariance towers (Fig. 14.9).
OM exchanges within estuaries
• Components of estuaries vary in Pn• Positive in surface waters, negative in bottom waters• Positive in salt marsh, negative in water column• Positive within seagrass beds, negative outside seagrass beds• Negative in upper estuary, positive in middle estuary n 2008 Testa and Kemp published a study in which they calculated net ecosystem production in different regions of the Patuxent River estuary and they found this interesting relationship with residence time. First they observed that CLICK - Net ecosystem production was very negative in the upper estuary - likely because turbidity from the river limited production - but it was less negative if the water sat there longer -if the residence time was longer, which probably decreased turbidity so there was more primary production, and decreased the input of organic matter from the river that fuels respiration.CLICK - They also found that Net ecosystem production was positive in the lower estuary because of nutrient input from the river and because it was less turbid, but it was less positive when the water sat there longer - when the residence time was longer - which probably gave more time for production and respiration to become more balanced.
Organism efficiencies
•C = P + R + U- C = consumption- P = production- R = respiration- U = unassimilation (excretion & egestion)• P / C = Gross growth efficiency• (C - U) / C = Assimilation efficiency• (P + R) / C = Assimilation efficiency• P / (P + R) = Net growth efficiency Food webs are all about efficiencies and for the organisms involved, those efficiencies have to do with their rates of consumption and with the rates of things they do with that consumed material. They can use it to produce new biomass, they can respire, and they can excrete and egest some of it. This last term was not part of the equations we used for bacteria because bacteria dont really excrete.CLICK - Gross growth efficiency is the ratio of production to consumption, or the fraction of consumed materials that are put into new biomass.CLICK - Assimilation efficiency is the fraction of food consumed that is not turned into detritus, and that can be calculated a couple ways. Consumption minus unassimilation divided by consumption. CLICK - Or production plus respiration divided by consumptionCLICK- Net growth efficiency refers to only that material that contributes to the organisms metabolism. Production divided by production plus respiration. This same equation is used for bacterial growth efficiency.