Marine Ecology

What is a species?

An interbreeding group of organisms which are unable to generate young, which are themselves reproductively viable, with any other species

Heterotroph

An organism that cannot manufacture its own food and instead obtains its food and energy by taking in organic substances, usually plant or animal matter. All animals, protozoans, fungi, and most bacteriaare heterotrophs. Compare autotroph .

Cold Seeps

Areas that produce lower temperature fluids where natural gas and methane gas seep into the water in the deep ocean. Found in the Gulf of Mexico. Also biodiverse area with chemosynthetic bacteria. Hydrogen sulphide and methane are the energetic molecule. The decomposing remains of dead bodies from falls also produce methane and hydrogen sulphide, prime sources for chemosynthesis. They work as island hop for dispersal.

Evolutionary effects of gear selection

Breeders equation: predicts evolutionary change in a trait

Diel vertical migration, three modes

Nocturnal migration Twilight migration Inverse migration

Primary Production

Primary productivity is the rate at which energy is converted by photosynthetic and chemosynthetic autotrophs to organic substances. no or very low contribution by higher plants Macroalgae show high production cabapilities, shallow coastal waters, inter tidal, normally benthic Microalgae are microscopic (2-200um) organisms colonising all euphotic water, most important group for marine primary production (!) secondary production of zooplankton, nekton and benthos is directly linked to microalgae, their primary food source

redfield ratio, deepwater vs phytoplankton

Redfield ratio: C:N:P = 106:16:01 C N P ratio measured in phytoplankton and deepwater very similiar. not sure what causes what (one theory = when algae (phytoplankton) gets decomposed, all it's parts are again available as nutrients in the deeper water, but this theory is controversial -> it could also be the other way around)

redundancy hypothesis

Redundancy hypothesis entails that the more species are present in an ecological unit, the rate of ecosystem function also increases but up to some point, beyond this point species become redundant and does not have any additional affect to the ecosystem functions, thereby the loss of certain species has no primary effect to the diversity of an ecosystem

Godzilla

Very strong ENSO event is termed as Godzilla El Nino as in 2015-16.

Digestion: Micronutrients

Vitamins and minerals are mentioned as micronutrients, they are required in small amounts

oceanic acidification (OA)

The process by which an increase in ocean CO2 causes more CO2 to be converted to carbonic acid, which lowers the pH of the water.

Trophi

The process of feeding, obtaining nourishment, nutrition

Secondary production

The production of biomass by heterotrophic organisms measured as the increase in biomass over time -> production is a proccess -> biomass is an amount

Definition Ecology

The science describing interactions between organisms and between the organisms and their abiotic environments.

optical remote sensing techniques

- aerial photography - airborne laser bathymetry (LiDAR) - satellite imaging (multispectral & hyperspectral imaging) - underwater photography and video (from AUV/ROV) - underwater hyperspectral imaging (UHI)

Specific metabolic activity of an organism is dependent on...?

...the size of the organism. It decreases rapidly with increasing size! small organisms are responsible for almost all metabolism in the sea. Yea!

What is primary production?

- a rate - mass per area per unit time -difficult to measure bc it varies so much in time/space/ecosystems and there are many definitions of it - exact measurement not possible

Bacteria and Archaea

heterotrophic marine plankton prokaryotes take up dissolved carbon (diameter 0.1-0.6 µm)

Secondary producers

heterotrophs - bacteria - ciliates - copepods - bigger organisms (fish, mammals etc) --> sometimes also called tertiary producers

How to calculate secondary production

input needed: - density for each year class (number/area) - mean individual wheight per year class production (mass) = mean density * increase mean body weight (growth rate)

Morphplogy

a branch of biology that deals with the form and structure of animals and plants

PEG Model Eutrophic

bi-model second peak is less nutritious

Autotrophic

carbon source: inorganic (CO2)

Heterotrophic

carbon source: organic matter

Auxotrophic

carbon/energy source: light/CO2 but with requirements of specific essential components

Mixotrophic

carbon/energy source: light/CO2 or organic matter live as photosynthetic autotrophs in the presence of light, but absorb organic nutrients as heterotrophs in the absence of light

What determines the mixing depth in fall?

during fall, the surface cools down again, and the entire water column eventually becomes fully mixed

Primary production values in different ocean provinces

open, nutrient poor ocean: ca. 50 (g C) / (m^2 yr) coastal waters: 100-150 (g C) / (m^2 yr up-welling coastal areas: ca. 300 (g C) / (m^2 yr

Ecosystem services

the processes by which life-supporting resources such as clean water, timber, fisheries, and agricultural crops are produced = out natural capital

Remote sensing

the science of obtaining information about objects or areas from a distance - non intrusive - can be from both short and long distances - acoustic remote sensing - optical remote sensing

Otolith

"earstones" hard, calcium carbonate structures directly behind the brain of bony fishes - aid fish balance and hearing - different species have different shapes and sizes - can be used for age determination

The multi-dimensional space of eco-clines

# There are always more than one eco-cline exposed to the organisms, but some may be more important than others # The living conditions for a species at any location is 1) the sum determined by all its abiotic factors (eco-clines) and 2) the biological interactions with other species/groups # In other words, the crossroad of all important eco-clines, and the ecological interactions between the species that can compete efficiently at these conditions are decisive # The competitive abilities of the organisms, determining their ecological niches

The establishment of patterns of organisms are driven by

- Eco-Clines; gradients in abiotic factors and - Physiological / ecological characteristics of the organisms

Functional resonse type 2

(cyrtoid) functional response in which the attack rate increases at a decreasing rate with prey density until it becomes constant at satiation. Cyrtoid behavioral responses are typical of predators that specialize on one or a few prey.

Functional response type 1

(linear) response in which the attack rate of the individual consumer increases linearly with prey density but then suddenly reaches a constant value when the consumer is satiated.

Functional response type 3

(sigmoid) functional response in which the attack rate accelerates at first and then decelerates towards satiation. Sigmoid functional responses are typical of generalists which readily switch from one food species to another and/or which concentrate their feeding in areas where certain resources are most abundant.

NF cod

- 400 years old cod fishery in NFL collapsed in early 1990s -> collapse caused by a combination of overfishing and unfortunate climate factors - even after 25 years moratorium stock is still not fully recovered -> recruitment ability reduced due to strongly decimated stock size -> in absence of cod, other species (dogfish, skates) have flourished reasons: - new technology - international fleet - too high quotas - bad monitoring

4 main threads of biodiversity

- Ecological (biomes, ecosystems, habitats..) - Organismal (kingdoms, phyla, species..) - Genetical (populations, individuals, genes, ...) - Physiological (energy source, carbon source, e-acceptor, e-donor, metabolic functions)

Ekman Transport

- Ekman transport is the direct wind driven transport of seawater - Boundary layer process - Steady balance among the wind stress, vertical eddy viscosity & coriolis forces

Biodiversity and ecosystem functioning

- Accordingly, for species-rich ecosystems, many species are according to rivets theory likely to have similar functional role within the ecosystem - Does this imply that some species are redundant, that their extirpation would have no consequences for ecosystem function? - This may in case mean that some key species are more important than others? - Basis for functional biodiversity concept

COP21 Paris Agreement

- At the Paris climate conference (COP21) in December 2015, 195 countries adopted the first-ever universal, legally binding global climate deal - A long-term goal of keeping the increase in global average temperature to well below 2°C above pre-industrial levels; - Limit the increase to 1.5°C, since this would significantly reduce risks and the impacts of climate change; - Need for global emissions to peak as soon as possible, recognising that this will take longer for developing countries; - Undertake rapid reductions thereafter in accordance with the best available science.

Which (3) variables will normally describe the ecological state?

- Biomass, numbers or weight (ecosystem structure) - Growth rate, production (ecosystem function) - Biodiversity, variety of life (taxonomic or functional biodiversity) --> Ecosystem funtion is most important

Dark reaction (part 2 of photosynthesis)

- Calvin cycle in the Stroma - fixes CO2 - forms organic material 4 NADPH + ATP + CO2 -> CH2O + H2O

Side products of aquatic primary production

- Cellulose - Lignin - Food / nutrition - Amino acids - Lipids - Pigments

Which fish species are abundant in Norway and therefore commercially exploited?

- Cod - Herring - Flatfishes - Capelin

Natural Disturbance

- Disturbances act on different scales and with different frequencies. - Natural disturbances, such as ocean-level change, ocean temperatures and ocean currents, usually take place over extended time periods (centuries, millennia). - Other natural phenomena have a shorter time scale (hurricanes and cyclones, pests). - Natural disturbances contribute to the diversity between ecosystems

Adaptations of deep-sea animals II

- Do not do vertical migrations (pressure difference is too high), so they lack swim bladder - Very large mouths and expandable stomachs. - Small in size but bigger than fishes from twilight zone (most energy is devoted to growth, rather than reproduction) - Energy-saving adaptation is accentuated (sluggish, have watery muscles and weak bones) - Presence of pressure-resistant enzymes

Very small organisms are responsible...

...for almost all metabolism in the sea. They rule!

Bycatch discard

- Estimates of "Total landings" are probably grossly underestimated because they don't include bycatch/discards (dumped during the fishery) - Dumping may be due to undersized fish, non-commercial species, or non-legal species in the catches - Dumped bycatch probably amounts to as much as 27% of the total world catch --> serious problem for the productivity of legal species and stocks, for maintenance of the biodiversity, and for the oceans' possibility to feed a growing world population.

River transport of terrestrial discharge

- Estuaries are strongly influenced by the freshwater runoff, and the materials which the rivers carries with them to the sea. - Worldwide, ca 70% of the sediments are contributed by rivers. - Power plants, agricultural discharge, flood debris, size of the precipitation area and estuary decide how strong the sedimentation is.

Adaptations of deep-sea animals III

- Finding a mate is difficult! -> Anglerfish releases pheromones and attaches for the rest of their lives (male parasitism) (Pheromone: a chemical substance produced and released into the environment by an animal, especially a mammal or an insect, affecting the behaviour or physiology of others of its species.) - Many are hemafrodite (Hermaphrodite: organism that has complete or partial reproductive organs and produces gametes normally associated with both male and female sexes.) - Many use their bioluminescence to attract a mate - Some of them aggregate

Factors affecting the GROWTH and REPRODUCTION rate of heterotrophic plankton and nekton

- Food concentration, size and shape, nutritional quality, more? - Taxonomic group or species, their genetic properties - The size of individuals, within and in between species - Physical factors, i.e., temperature, affects all metabolic rates

Methods to study marine systems

- Historically, most studies of the ocean space have been fragmented - "Sampling blindly, in the dark" - Advanced observation and sampling methods are first becoming available in our time, a shift in paradigm - We can bring our senses and perception into the ocean

For herbivore grazing animals, the potential food amount is the double of the primary production. Why?

- If a food amount of 1 unit is available for a population/community (from PP), and if 50% (Ydet) is released as defecation/dead biomass and eaten again ........ - Then the total food amount is the double of the initial food amount, or 2 units (bit more complicated calculation) --> For herbivore grazing animals, the potential food amount is the double of the primary production

Aerobic respiration

- Important metabilic pathway which takes place in heterotrophs - When oxygen is present, organic compunds are oxidized using O2 as an electron acceptor to produce CO2 and ADP - Reverse equation of photosynthesis - Main source to gain energy in heterotroph aerobic bacteria, fungi, algae vascular plants and animals (when glucose is oxidized)

Origin of life

- In the oceans - Alkaline hydrothermal vents may have played a role - Photosynthesis! When Organisms became able to use carbohydrate to produce oxygen

"Species poor ecosystems are expected to be those that are most vulnerable to external forcing factors" (Kaiser et al) -> Challenge this dogma

- Is really the number of species (species richness) that important for ecosystem integrity? - Can species richness alone reflect stability of ecosystems and how they function? - Is species richness really a useful concept for management of marine ecosystems?

PP: who are the actors?

- Mangroves - Seagrass beds - Macroalgae (kelp forests) - Coralline algae (Maerl beds) - Phytoplankton ! (responsible to 40-50% of earths PP)

Marine vs. terrestrial ecology

- Microbes dominate the biological activity in marine ecosystems, e.g. photosynthesis and respiration - Marine organisms live in a 3D world - Marine microbial food chains with more than 5 trophic levels - Macrobes (visible) are far more dominant in terrestrial ecosystems, and food chains are shorter - Soil ecosystems can have similiarities to marine

Adaptions of animals from the deep ocean floor

- Most are deposit feeders (feeding on small pieces of organic matter that have drifted down through the water and settled on the bottom) - Spiky spines (sea urchins), which allows them not to sink in the soft mud - Some species are found in herds to facilitate mating - Deep sea corals (found 2000m in the Norwegian fjord) have large polyps to make sure it catches food - Developed sense of smell and have an expandable gut in some scanvanger amphipod - Gigantism and long life - Some scavenging fishes are larger, muscular and active - Some species only reproduce after finding enough food

Rythers principal food chains (outdated)

...for open ocean, coastal and upwelling regions

Norway / EU fish stock management: issues

- NO / EU do not agree on the management of certain stocks -> regulated seperately - joint management plans lacking or need updates - the EU's landing obligation is being gradually introduced from 2016, but still significant differences between the regulations

Definition productivity

- Net primary production tells us how much energy and organic material is available to the heterotrophic community - Net community production tells us about the balance within the community as a whole i.e. whether the community is growing or declining - The two processes of photosynthesis P and respiration R are out of phase so there can be places and times when and where: R>P or P>R

Adaptations of deep-sea animals

- No need to countershade - Most animals are black but some are also red - Bioluminescence is still found in the upper part of the bathypelagic zone (photophores are usually on the head and sides, rather than ventral part of the body) - Light sensitive eyes are not needed - Some are blind and non- bioluminescent.

future challenges for measuring PP

- Often limited funding for long-term monitoring - Often long-term data sets are not continuous - Comparability is often limited between data sets due to methodological biase

Anthropogenic Disturbance

- Oil spill - Destruction of coral reefs - Eutrophication - Waste - ...

Effects of climate change

- Ozone depletion - Thinning of Glaciers - Permafrost melting - Temperature increase - Sea level increase - Ice free Arctic - Coral bleaching - Changes in precipitation pattern - Extreme events like storms - Drinking Water scarcity - Conflicts of animals with humans

size structuring in marine food webs

- P/B ratio higher in smaller organisms - Most organisms prey on others that are much smaller than their own size - Strong correla-on between body mass and trophic level

Primary production (II)

- Primary production is the starting point of all life in the oceans - Fundamental food source and basis of food webs - When considering production of new biomass, both production and loss processes (eg decay, grazing) need to be considered - Inorganic carbon sources (CO2 or HCO3-) are used to built-up organic matter

Satellite imaging

- Provides continuous stream of imagery - Compared to other RS techniques: less time-consuming, provides better coverage, higher repeatability - One of the major applications is change detection - Spatial resolution (ground sample distance, GSD): from <1 m to >1000 m, depending on sensor and altitude - Higher orbiting altitude: wider swath width, shorter revisit time, lower spatial resolution - Lower orbiting altitude: narrower swath width, longer revisit time, higher spatial resolution - May be used for mapping and monitoring: chl a, total suspended matter (TSM), cDOM, coral reefs, mangrove forests, submerged aquatic vegetation, changes in vegetation cover, sandy bodies etc. - Multispectral and hyperspectral imaging available (swath width: Streifenbreite)

General bioenergetic framework (for secondary producers)

- Resource acquisiton (feeding & assimilation) - Storing energy and nutrients - Maintain vitality & homeostasis, repair broken biochemical machinery, ... - Somatic growth - Reproduction (adults) - Maturation (juveniles) (somatic = adj., "relating to the body, especially as distinct from the mind")

Eutrophication

- Rivers supply plant nutrients (N,P) to the estuaries. - Initiate phytoplankton blooms which may spread over vast distances with ocean currents. - Results in substantial downstream ecosystem disturbances. - Red tide caused by dinoflagellates Karenia, Alexandrium - Shell fish poisoning and need depuration before use

Functional diversity - combining structure and function [Concluding remarks lecture 2]

- Species can be grouped according to their function in the food web/ecosystem, not according to taxonomy/species name - They can then for example be grouped according to their position in the food web - their trophic level, which express their function - Functional diversity may better than species richness reflect the state of the ecosystem - state assessment is the overall goal of management to deduce - The need to determine species names is not that important, their function is more important - Functional diversity is the most relevant basis for implementing ecosystem protection, which will indirectly protect the key species

Ecosystem function

- Species/group activities, their role in ecosystem - Species/group interactions (c.f. interaction mechanisms) - Interaction with abiotic environment

Ecosystem structure

- Species/group richness - Biodiversity of species/group

Mussel watch program

- Started in 1986 - Appoximately 300 sites - Over 150 organic and inorganic contaminants measured. - Polycyclic aromatic hydrocarbons (PAH), Metals - Polychlorinated biphenyls (PCBs) - Pesticides, New contaminants of Emerging Concern (CECs)

How is the issues of biodiversity handled in marine resource management / conservation?

- The abundance of higher taxonomic levels (e.g., phyla and classes) are higher in the ocean than on land - Most marine species are unknown, microscopic species are more dominant - is species richness then a relevant concept? - Regional and globally representative data are scarce - sampling challenges and less research efforts

Is functional biodiversity more useful than species richness for assessment of ecological state in marine ecosystems?

- The concept of Functional Biodiversity works for both known and unknown species - In functional biodiversity, "functional ecological groups" replaces "species" - Species are assigned to a functional group, using relevant criteria for the group

Present fishery status

- The stagnation and decline in global fisheries is due to heavy overexploitation of most species and stocks. - The management of these resources has failed in what has traditionally been their overall goal; to secure maximum sustainable yield (MSY). - Fisheries in principle is a "renewable natural resource", representing important protein source, particularly for poor nations. - The reasons are many... --> high demand --> insufficient biological knowledge --> unwanted side effects of catch regimes --> short term economic gain --> inadequate political mechanisms for control --> lack of a rational overall plan for resource exploitation.

What is deep sea?

- all the water and seabed beneath the edge of the continental shelf (ca. from 200m deep) - largest habitat on the planet --> least known habitat, too - divided in: -> mesopelagic -> bathypelagic -> abyssalpelagic - oxygen minimum zone - seafloor is irregular with trenches, sea mounts and mid-ocean ridges

What drives secondary production?

- animal size - type of animal community - trophic level - transfer efficiency - # of levels in food chain

Fish stock

- annual mortality will be strongly affected by the catch pressure (fishing mortality), which comes on top of natural mortality - for cod stocks: natural mortality ~40% and fishing mortality ~40%. total annual mortality = 80% - the stock may then be left without the possibility of adequate recruitement, and is hence overexploited

Conservation

- attempts to protect and preserve biodiversity - it focuses on both biological and social factors which is needed for successful conservation efforts.

Stoichiometry in primary producers

- autotrophs are considered to be rather flexib in their stoichiometry depending on the nutrient status of the system - p-limitation in autotrophs causes C-accumulation

Factors affecting the harvestable production in upwelling areas

- beside the rate of nutrient input from deep water, the duration of the upwelling events is also important - one observation is that moderate rates of upwelling (moderate supply rates of nutrients) tends to result in large phytoplankton cells and the shortest food webs

Ocean color

- can be used to assess phytoplankton dynamics - is commonly used to estimate chlorophyll a concentration (by using at least multispectral imaging)

Effects of eutrophication on secondary production

- can increase SP through increase in PP - mild periodic hypoxia: --> increased pulse of energy to mobile predators, because benthic animals leave their burrows - sustained hypoxia: --> always negative for predators 7

how diameter of cells influences the DBL?

- cells < 1 um in diameter: molecular diffusion is adequate for the resupply of nutrients - cells > 1 um in diameter: molecular diffusion is a major limiting factor -> mechanisms to change the characteristics of the DBL around the cells are important (e.g. surface structures)

How is the deep ocean?

- cold (-1 - 4 °C) - high pressure (1 atm every 10m) - stable - dark - essentially no productivity (except hydrothermal vents, cold seeps) - sparse life and little food

Phytoplankton (II)

- come in many sizes, shapes and functional groups - in terms of size, they are found among the Pico-, Nano- and Microplankton

Threats to the deep sea

- deep sea fishing - whale hunting - deep sea mining, oil and gas exploration - carbon storage - submarine communication cables

How to assess disturbance

- enormously complex interactions in marine ecosystems, therefore critically important to ask the right question. - Long-term ecological changes strongly influenced by a fluctuating environment, very difficult to sort out importance of single factors among a multitude of (possibly confounding) milieu effects. - Sometimes necessary to do laboratory experiments as a support to time series of climatic or ecological data. - Monitoring time series must be designed so that they have statistical power for detecting trends in a time series.

What is the production potential of the worlds oceans?

- estimates 22 - 2000 million tonnes / year - most estimates between 100 - 200 million tonnes (authorised figure by FAO)

Dinoflagellates

- eucaryotes - on of the largest groups of phytoplankton (but smaller than diatoms) - most dinoflagellates are photosynthetic (autotroph) but a large fraction are mixotrophic (eat prey) --> therefore, their species can either be phyto or zooplankton - cause red tide -> shellfish poisoning

how to measure the secondary production of a cohort?

- examine the growth of individual organisms and population mortality two approaches: - measurement of production of biomass due to growth - measurement of the elimination of biomass due to mortality (all biomass that is lost due to mortality had to be produced in the first place) A species with equivalent growth but a lower mortality rate will reach a higher population biomass maximum and will therefore have a higher production.

Rythers estimated potential for world ocean fisheries?

- first one to come up with a prediction that was close to todays - he predicted 240 mil. tonnes fresh weight of fish produced annually -> off which 100 mil. tonnes harvestable methods: - divided global oceans into three provinces --> each with characteristic PP, food web structure and ecological efficiencies (used a simple trophic-dynamic model combined with vast experience)

Norway / EU fish stock management: more issues (II)

- fishery authorities have not monitored the large increase in WRASSE fishing sufficiently - decline in coastal COD& and SPRAT has not been reacted to adequately - overall control resourced are not utilized well enough - controls too well predictable - follow-ups too weak

Large food falls

- food for scavangers (amphipods, hagfish and brittle stars) - scavengers can feed on carcass in less than 6 months (slow decomposition) - have an adaptation to starve and gorge (=vollfressen) (sporadic event) - some bivalves can eat even wood (i.e. oysters, mussels) - chemosynthetic bacteria support a community (island hops, every 9 to 30 km) - danger of whale hunting

Deep sea bacteria

- grow slowly under cold and high pressure - surface bacteria died

Cod family

- highly successful group of modern, advanced fishes, mostly in the Atlantic. - mostly distributed in the northern temperate climate zone with - those fish species face specific problems related to cyclic, seasonal production conditions. - important events in life must match nature's seasons in order to secure a successful reproduction. --> their so-called match-mismatch model for recruitment

Light reaction (part 1 of photosynthesis)

- in the Thylakoid membrane - converts light into metabolic energy 2 H2O + light -> 4 NADPH + ATP + O2

When does fish spawning usually take place in Norwegian latitudes?

- late winter and early spring (january - april)

how to measure primary production

- look at final product: measure O2 - measure increase in biomass (fixed carbon) - look at factories which fix carbon (measure chlorophyll)

What happens if one functional group of a foodweb is lost?

- loss of functional biodiversity (=problem) - prof: if just one species dissapears not that bad, if the whole group gets extinct its bad

Oxygen minimum zone

- oxygen minimum zone (OMZ) - low oxygen levels due ti bacterial respiration -> below OMZ: most organic matter has already decayed - oxygen at surface is provided by atmospheric diffusion and oxygenic primary production - oxygen to deep layers is supplied by thermohalinecirculation (conveyor belt)

Factors affecting feed intake in filter-feeding zooplankton

- prey size - prey concentration - physical shape of prey - physical-chemical conditions, the physiological constraints of the organism/species

Deep ocean floor

- sediment = soft, fine, thick mud - sediment can be divided in clay (oligotrophic gyres) or biogenic oozes: siliceous oozes or calcareous oozes - Hard substrata is uncommon: hydrothermal vents, sea mount, trench walls and whale bones (important for dispersal of sessile organisms!) Clay = Ton, Ooze = Schlamm

Recovery Rate

- short for small-scale disturbances; from seconds to weeks - recovery rate increases strongly with the geographic and temporal scale Norway example: When the shallow-water fish fauna in coastal waters in South Norway was almost wiped out by an algal bloom some decades ago, it took surprisingly short time (1-2 years) before it was intact again. Therefore, aspects of the mobility of the involved organisms is also part of the picture with respect to re-colonisation.

acoustic remote sensing techniques

- sidescan sonar - echo sounder reflection (single & multi beam) - seismic reflection

Photosynthetic reaction

- specialized, light sensetive pigments (chlorophyll) absorbe light energy which is subsequently transferred to reduce CO2 to organic compounds - CO2 is fixed within the Calvin cycle - First step in teh reduction of CO2 is catalysed by the enzyme RUBISCO - high supply of CO2 at the active site of RUBISCO is needed 6CO2 + 6H20 ---> C6H12O6 + 6O2

Grouping of plankton are made based on

- taxonomy - life cycle, stage - size - physiology -> and their function, functional groups, what they do, what they eat, their trophic role !

What determines the mixing depth in winter?

- temperature is key factor - during winter, the ocean is warmed by the sun to a neglible extent --> the water column has a more or less uniform temperature (no distinct layers), and is therefore fully mixed

decomposition chain

- there are organic and inorganic losses in the food web, mentioned as decomposition - all heterotrophic organisms contribute to decomposition, breakdown of organic matter - inorganic components which are released = mineralization

what are micro electrodes used for?[carbon and oxygen flux measurement]

- these highly sensitive electrodes (pH, CO2, O2, sulphur, nitrogen, etc) can measure MICRO-SCALE FLUXES in photosynthesis and respiration at surfaces such as biofilms and sediments (penetrate very thin layers, cool!) cool for in-situ (in field tests)

Photosynthesis

- use light as energy source (autotrophy) - use CO2 (or HCO3-) ti build up biomass

Physical mechanisms that create upwelling

- wind - coriolis effect - vertical eddy viscosity -> resulting in Ekman Transport

Utermöhl-microscopy [Biomass estimation]

-> used to estimate PP - fixed plankton sample with known water volume is filled in "sedimentation tower" -> all cells and small org will collect at bottom in a counting chamber - this sample is then analyzed by microscope pro: high taxonomic resolution contra: can be time consuming, difficult to count cells <3um

Flow cytometry [Biomass estimation]

-> used to estimate PP particles and cells (sample) are aligned in a high speed water stream passing a powerful laser beam (hole is so small that particles have to pass single wise) -> scattering of laser light is measured while a particle passes species / group identification can be supported by photo imaging pro: extremly fast and accurate, onboard sample analysis possible contra: low taxonomic resolution, usually not suited for large phytoplankton species

Pigment based analyses [Biomass estimation]

-> used to estimate PP pigment quantification (especially chlorophyll a) can be used as a proxy for PP because there is a close relationship between chlorophyll concentration and photosynthesis at any given light intensity. different methods: - spectrophotometry - fluorometry - chromatography pro: fast and accurate contra: low taxonomic resolution

remote sensing [Biomass estimation]

->used to estimate PP sattelites/aircraft/UAV with colour sensors color recording of surface water masses can be allocated to concentrations of certain dissolved constituents such as chlorophyll a and other algal pigment concentrations pro: large-scale estimation, global estimates contra: only measures surface pigment (deep chlorphyll maxima not included), very expensive, scarce funding

Ecological interaction mechanisms

-Predation (plus-minus) -Competition (plus-minus, minus-minus) -Territoriality (plus-minus, minus-minus) -Parasitism (plus-minus) -Commensalisms (plus-no) -Mutualisme (plus-plus)

Rubisco

-The most abundant protein on earth - Performs Carbon Fixation in the Calvin Cycle - Ca 50% of the proteins in planktonic algae

effect of different food chain lengths on transfer efficency

... and therefore effect on secondary production!

number if trophic transfers (n)

1-5 generally fewer steps in nutrient rich waters than in nutrient poor

Effects ocean acidification (OA) on heterotrophs

1. Alterations in calcifying organisms (e.g. coccolithophores, corals, molluscs) 2. Acidification of body fluid (hypercapnia) • Alterations in herbivores due to changes in food quality

What's the difference between Arctic and Antarctic regions in terms of PP?

1. Arctic ocean: nutrients in excess 2. Antarctic ocean: Major nutrients (N, P) are available but micro-nutrients limited Antarctica is a so called "High Nutrients Low Chlorophyll Region" (HNLC)

2 different measures of primary production

1. Carbon and oxygen flux measurements (O2 uptage/realease, CO2 assimilation/release) 2. Biomass ("standing crop") estimations (cell or pigment based estimations) cell based: microscopic analyses, flow cytometry pigment based: remote sensing, spectrophotometry

In which forms does dissolved inorganic carbon occur in seawater?

1. Carbon dioxide (CO2) 2. Carbonic acid (H2CO3) 3. Bicarbonate ions (HCO3^-) 4. Carbonate ions (CO3^2-) The proportions of these forms in seawater are in equilibrium

PP in temperate waters, an overlook

1. Complex seasonal dynamics of light and thermal stratification 2. Distinct seasonality patterns in primary production → Spring and autumn blooms in phytoplankton → Low standing stocks in summer and winter 3. High primary production due to high nutrient availability 4. Ocean colour: brown, olive (dominance of diatoms) 5. High secondary production (high fisheries yield)

Effects ocean acidification (OA) on autotrophs

1. Enhanced phytoplankton growth and primary production processes at high CO₂ conditions 2. Changes in phytoplankton quality (C:N:P) due to a higher availability in CO₂

Major factors for primary production

1. Light availability: only in the euphotic zone, ca 0-200m 2. Nutrients: can be exhausted in the upper water column, but are generally available in the deep ocean 3. Stability: Promotes algal growth in surface waters 4. Mixing: Re-cycling of nutrients from the deep ocean to the uppermost surface layer --> it's the physics of the water body that controls PP!

PP in tropical and subtropical waters, an overlook

1. Permanent thermal stratification due to solar heating of surface waters 2. High irradiance and a high light penetration depth (> 200 m) 3. Reduced mixing to surface water layers leads to lack of nutrients and low primary production (nutrient limitation) 4. Ocean colour: dark blue ('deserts of the oceans') 5. Low secondary production (low fisheries yield) BUT 6. Monsoons can support upwelling (mixing) --> inputs of nutrients and distinct seasonality patterns even in tropical/subtropical reagions 7. Tropical storms can support the mixing of the water column --> input of nutrients from deep layers to surface waters leading to phytoplankton booms

Important groups of phytoplankton

1. Pico-cyanobakteria 2. Diatoms 3. Dinoflagellates 4. Prymnesiophycea 5. Cryptomonads 6. Green algae 7. Silicoflagellates

What is generally to consider when measuring primary production?

1. Primary productivity can vary due to many factors, e.g. depth, time of day, season and region etc. -> heterogeneity in time and space 2. Algal photosynthesis occurs simulatenously with cellular respiration 3. Natural phytoplankton communities are difficult to be completely separated from heterotrophic consumers in the same size fraction - Problems: phytoplankton biomass can be reduced due to predation during incubation experiments; hard to measure gross primary production 4. Each measurement method has its built-in biases (be aware of advantages and disadvantages when planning an experiment

PP in polar waters, an overlook

1. Significant mixing of nutrient-rich deep water with surface waters 2. BUT: Light availability is low due to the short day-length and shallow sun-angles in winter 3. Seasonality: Usually one single peak of primary production when light availability is high enough to support algal growt ==> Primary production in polar waters is restricted to short seasonal windows when light is available

oceanic gyres

1. Surface current loops caused by trade winds and westerlies, acted on by the Coriolis effect 2. Transfer heat from equator to polar regions 3. Conspicuous features of the Atlantic, Pacific, Indian and Southern Oceans 4. Anticyclonic gyres: move in clockwise direction (northern hemisphere) and anticlockwise (southern hemisphere) → tend to deepen the thermocline moving water to the centre of the gyre → low nutrients leading to low primary production 5. Cyclonic gyres: move in anticlockwise direction (northern hemisphere) and clockwise (southern hemisphere) → mixing of the water column from below the thermocline into surface waters → High primary production

Measures to undertake conservation II

1. a broad general perspective 2. a longterm perspective based on the precautionary principle 3. an adaptive management 4. local peculiarities and differences 5. to work in accordance with natural processes and economical capacity 6. to involve all parts in the process 7. support and involvement from the central authorities and local administration 8. a combination of remedies to simplify co-operation between administrative sectors

What is phytoplankton succession influenced by?

1. abiotic conditions: temp, salinity, nutrients, light 2. grazing by micro- and mesozooplankton

Principle methods of food intake

1. active non-selective filtration harvesting of feed particles from the water (most zooplankton, also larger animals) 2. identification of individual feed items, attack and consume (fish and some zooplankton) 3. take up particles by pinocytosis (small protozoan zooplankton) 4. take up molecules (bacteria)

Primary producers: order of magnitude in size (from small to big)

1. bacteria (>1 um) 2. microalgae (light microscope needed LM 400x vergr.) 3. datoms (20-200 um, LM 200x vergr.) 4. phytoplankton (colony made out of single cells, >200um) 5. seagrass / macroalgae (you can pick/see them)

4 growth phases

1. lag 2. exponential 3. stationary 4. senescent

Measures to undertake conservation

1. start with children - conservation depends on attitude of individual person - attitudes are shaped early in life 2. measures to undertake conservation - pursue common society on the need for conservation through awareness programs 3. economic intcentives - usually environmental assets are considered free due to which they are exploited - economic intcentives seek to correct this by setting a price for environmental damage 4. legal protection - marine protected areas, green policies, closed seasons, ban of tourism 5. military force - actively protect environments by regulatory force - prevent illegal fishing or mining - sustainable usage of resources 6. IUCN red list for species - norsk red list of species 7. integrated coastal zone management - ICZM aims for coordinated application of the different policies affecting the coastal zone and related to activities such as nature protection, aquaculture, fishery, agriculture - EU has asked its members to come up with national strategies for coastal zone management

Simplified taxonomix grouping of the main phytoplankton groups (for food chain studies)

4 practical groups (this grouping not size relevant) - Picocyano-bacteria - Diatoms - Dinoflagellates - Small pigmented flagellates

Visible light wavelength

400 - 700 nm = the light that is relevant for PS also called photosynthetically active radiation (PAR)

Ecological transfer efficiency, what is correct?

5 - 35 % depending on source 10 % commonly used if nothing more is known

How many of the world's fishery resources are overexploited?

80% (FAO estimate)

carbon assimilation efficiency II

= A/I = (G+R)/I = (I-F)/I A: Assimilation I: Food intake, consumption, ingestion G: Growth, biomass production R: Respiration F: Defecation, production of faeces, zero for bacteria

gross primary production

= P The total primary production of an ecosystem. (P = Photosynthesis)

net primary production

= P - Ra "net photosynthesis" (P = Photosynthesis, Ra = algal respiration)

Net community production (NCP)

= P - Rc "net ecosystem production" (P = Photosynthesis Rc = Community respiration)

Carbon growth efficiency

= growth yield = G/I = G/(G+R+F) I: Food intake, consumption, ingestion G: Growth, biomass production R: Respiration (only for carbon) F: Defecation, production of faeces, zero for bacteria

Food chain vs Food web schematic

A comparison of a hypothetical marine food chain and web. Both begin with 100 arbitrary units of primary production. In the food web, two carnivores species (A and B) compete for the supply of herbivorous zooplankton. Only half of the herbivores are consumed by each species. Fish do not eat species B, so their principal food supply is less by 50%.

Trophic state

A description of the overall conditions in the ecosystem, including biomass and flows of energy and materials

Gyres are:

A gyre is any large system of circulating ocean currents, particularly those involved with large wind movements. Gyres are caused by the Coriolis effect; planetary vorticity along with horizontal and vertical friction, determine the circulation patterns from the wind stress curl

Diversity indices

A quantitative measure that reflects how many different types (such as species) there are in a dataset (a community), and simultaneously takes into account how evenly the basic entities (such as individuals) are distributed among those types.

Scale of Disturbance

A tight coupling exists between the time- and space scales in which disturbances occur. 1. chemical reactions between sediment particles, viral-, and bacterial processes. 2. minute-scale predation and metre-scale 3. bioturbation 4. tidal cycles

Endocytosis - Phagocytosis

A type of endocytosis in which a cell engulfs large particles or whole cells

Endocytosis - Pinocytosis

A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes.

Diatoms

A unicellular photosynthetic alga with a unique glassy cell wall containing silica; camonbert boxes;

OSPAR

Agreement to reduce pollution flowing into sea from rivers in North-East Atlantic

metabolic theory of ecology

All organisms share common constraint on their metabolic rate, and this governs all ecological processes. -> heterotrophic (need org. substance) processes are more vulnerable to temperature changes than autotrophic (need C) ones! reasons: phenology (timing)

Energetics (on individual level)

Allocation and metabolism of food in zooplankton and higher animals (simpler in bacteria)

Bathypelagic and abyssalpelagic zones

Bathypelagic (1 to 4 km) Abyssalpelagic (4 to 6 km) Hadopelagic (> 6 km to 11 km) - No light at all - The bathypelagic and abyssalpelagic zones 1 to 2°C of temperature and salinity and other chemical property is constant) - Only 5% of food from the surface arrives there - Food and pressure causes the zonation of animals - Ocean bottom is included

Biomagnification

Bioamplification (or biomagnification) refers to an increase in the concentration of a substance as you move up the food chain. This often occurs because the pollutant is persistent, meaning that it cannot be, or is very slowly, broken down by natural processes. These persistent pollutants are transferred up the food chain faster than they are broken down or excreted.

Emiliana huxleyi in Trondheimsfjorden, July 2018

Bloom likely caused ba a combination of: - high light - low silicate - high carbonate saturation -> limiting diatoms - stratification of water masses Emiliana huxleyi = coccolithophore

How can chlorophyll a be measured by satellites?

By using imagers that are at least multispectral, color properties of pixels caused by chl a differences can be identified

Carbon:Nitrogen:Phosphorus

C:N:P ratio 106:16:1 (in healthy, actively growing algal cells)

Climate change definition

Climate change refers to a change of climate that is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and that is in addition to natural climate variability observed over comparable time periods

Emiliania huxley

Coccolithophores; E. huxleyi is the most abundant and widespread coccolithophore. most productive calcifying organism on earth. when water conditions are favourable, E. huxleyi often forms massive blooms in temperate and sub-polar oceans, and in particular at continental margins and shelf seas, sometimes the reflection from the blooms can be picked up by satellites in space.

Multivariate techniques

Combine two or more samples with respect to which degree they contain the same species or different species with variable frequency. They can incorporate both the species identity and abundance/biomass. The graph shows a MDS (multidimensional scaling) plot of fish and benthic societies in the Irish Sea by use of bottom trawl. Closeness on the plot means similarity of species composition and numeric value.

Decomposition

Decomposition, the breakdown of organic material by heterotrophic metabolism as a consequence of respiration, results in the production of inorganic carbon (as CO2 ), nitrogen (as ammonium), and phosphorus (as phosphate); the process is collectively referred to as remineralization (or sometimes simply as mineralization). Decomposition of organic material back into energy and inorganic material is a process to which all heterotrophic organisms contribute, although the microbes play a dominant role.

DSL schematic

Deep Scattering Layer

DSL

Deep Scattering Layer: well-defined horizon in the ocean that reflects sonar; indicates a layer usually consisting of fishes, squid, or other larger zooplankton Sonars were used during the WWII, which dicovered 'false bottoms'. DSL is from 300 - 500m (day) and at surface (night). DSL related to light. Deeper in full moon and even move when clouds pass. Air pockets from swim bladders from migrating fish reflect better the sound wave than watery animals (jelly fish, squid and other twilight animal).

Commercially important fisheries

Demersal (mostly bottom dwelling): - Haddock - Cod - Hake Pelagic (surface dwelling): - Sardine - Anchovy - Herring - Mackerel - Tuna Crustaceans: - Krill - Shrimp - Lobster - Crab Mollusks: - Oyster - Clam - Octopus - Squid

Nitrate respiration

Denitrification process in which denitrifying bacteria reduce nitrate and nitrite to nitrous oxide or dinitrogen gas NO3- > NO2- > NO > N2O > N2

Monod Model

Describes the dependance of growth rate u ("mü") on nutrient concentration

ENSO

El Nino Southern Oscillation, trade winds weaken & warm surface water moves toward South America. Diminished fisheries off South America, drought in western Pacific, increased precipitation in southwestern North America, fewer Atlantic hurricanes.

Milky water is caused by

Emiliania huxley

Primary sources of energy (II)

Energy source: light or redox reactions (breath, fermentation) Electron source (needed for reductions, using NAD+ or NADP+): litho (anorganic) -> i.e. nitrifying bacteria or organo (organic) -> i.e. animals Carbon source: Autotrophy (carbon only from CO2) -> i.e. freen plants Heterotrophy (carbon from organic compounds) -> i.e. animals

Digestion: Major nutrients

Energy yielding foods (carbohydrates and fats) and body building foods (proteins, essential fatty acids). They are required in high amounts.

Effect of climate change (higher temp) on PP

Enhanced grazing by heterotrophs at elevated temperature can have inpact on: 1. total phytoplankton biomass (net PP) 2. timing of phytoplankton blooms 3. dominance of specific, bloom forming species (e.g. inedible or grazing resistant species)

EIA

Environmental Impact Assessment compulsory forehand assessment of nature and possible impact on nature due to a project

Digestion: Enzymes

Enzymes are the most critical element of digestion. They break down complex nutrients in to simpler substances and facilitate their absorption in the intestine

Modeling bioenergetic processes

Feeding and assimilation rates - See separate card Reserve dynamics - Assimilation rate - utilization (catabolism) rate Maintenance rate - Absolute priority - Depends on size of organism Growth costs - Depends on the amount of structural biomass produced Reproduction costs - Depends on the amount of gonads produced

FRM

Fisheries Resource Management • Turtle Exclusion devices (TED) and ban on destructive gears • Population genetics and habitat suitability modelling for breeding ground identification • Soft coral propagation and artificial reefs • Mangrove conservation • Turtle and Sea cucumber conservation • Sea ranching • Prevent Ghost fishing • Programs to create awareness for sustainable fisheries and ecosystem conservation

Food chain vs Food web definition

Food chain: An abstraction describing the network of feeding relationships in a community as a series of links of trophic levels, such as primary producers, herbivores, and primary carnivores Food web: A network describing the feeding interactions of the species between its food and its predators

What determines the rate of energy aquisition (feeding & assimilation rate)?

Food quality - assimilation efficiency Food quantity - size of food items - density of food items Temperature Size of organism - the larger the organism, the higher the the ingestion rate (cells/h) Behavioral stimuli - demand driven feeding - predator presence (if predator around its prey will feed faster)

Chain reaction of a disturbance

From the source, a disturbing event can cause a chain reaction. I.e. soil erosion -> increased river transport of soil, humus, mud -> this may cover benthic habitats and reduce light -> cause coral reef deaths example of reduced light impact in Trondheimsfjord: the recent proliferation of the coronate jellyfish Periphylla periphylla; a non-visual feeder which out-competes visual feeders like fish larvae and fry

Schematic flow of energy and materials in animals

G: Growth, reproduction and mortality R: Respiration, CO2 F: Defecation of undigested food E: Excreted inorganic nutrients I: Feed consumption, feed losses

Gelatinous plankton

Jellyfish Hydromedusa Ctenophora Chaetognats

Yield-per-recruit model

Graphs showing the relation between: - total annual mortality - individual growth rate - total biomass ...in a population. Total biomass (number x weight) is typically largest at an intermediate age (MSY)

Important terms PP

Gross production = P Autotrophic respiration = Ra While community respiration = Rc Net primary production (NPP) = P - Ra -> NPP tells how much energy/organic material is available to the hereotrophic community Net community production (NCP) = P - Rc -> NCP describes the balance of the community (whether it is growing or contracting)

Reward dependent feeding

Just go out to "hunt" when there's sufficient food density

HELCOM

Helsinki Comission -> baltic sea protection / conservation

Different blood pigments that allow the uptake and transport of oxygen in the body

Hemoglobin (in humans and other vertebrates) Hemocyanin (invertebrates: molluscs and arthopods) Hemoerythrin (invertebrates: sipunculids, priapulids and brachiopods)

Protozoa

Heterotrophic marine plankton (nano-/micro zoo plankton); Protozoa is an informal term for SINGLE-CELLED eukaryotes, either free-living or parasitic, which feed on organic matter such as other microorganisms or organic tissues and debris 1. Heterotrophic nano-flagellates. Small (4-8 µm) flagellated cells without pigments, with one or more flagella, small grazers 2. Ciliates - medium sized (20-50 µm), ciliated organisms, most species are heterotrophic grazers, but some are autotrophic or mixotrophic, abundance normally <15 per ml 3. Foraminifera, Radiolaria - Not ecologically important in water masses *** compare Metazoa: multicellular eukaryotic organisms that form the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development. Also micro-meso zooplankton.

Mero-plankton

Heterotrophic plankton but only in larval stages i.e. Crustacean Fish Shellfish Polychaetes and more

Cladocera

Heterotrophic, marine holo-plankton --> Crustaceans "water flies", a dominant group in fresh water, not very common in the sea

Amphipods

Heterotrophic, marine holo-plankton --> Crustaceans large planktonic crustaceans, most important at high latitude

Copepods

Heterotrophic, marine holo-plankton --> Crustaceans many species, different sizes, complex life cycles, cosmopolite with world wide distribution

Krill

Heterotrophic, marine holo-plankton --> Crustaceans some dominate species, large shrimp-like individuals

HNLC regions

High concentrations of macro-nutrients but deficiency in micro-nutrients (Fe, iron limitation in PP) 2. Low PP, ocean colour: blue 3. Low secondary prod. -> low fisheries yield = Antarctic ocean, North Pacific, Equatorial Pacific (Galapagos) Portions of the ocean featuring High Nutrients and Low Chlorophyll. Biological reproduction is low even though surface waters have relatively high concentrations of nutrients (nitrogen and phosphorus compounds)

Evolutionary effects of fishery regimes

Human activity in form of fishing gear selection can lead to changes in biological (and behavioural!) traits of the populations over time.

density dependent or independent?

If r is constant, then population population dynamics are density independent If r depends on population size, then population population dynamics are density dependent (logistic growth). e.g. - Mortality is higher in crowded populations - Growth (production) rates are higher when competition for resources is low, i.e. at low population densitie

Feed uptake vs feed concentration

If the feed concentration (available amount of food) is getting higher, so is the amount of food ingested (R). but only to a certain point. Functional response

Anaerobic respiration

Important when oxygen does not occur in sufficient concentrations (eg marine sediments, oxygen minimum zones) - some organisms (anaerobic heterotroph bacteria and protozoa, not algae or plants) living in O2 deficient zones -> use nitrate and sulphate compounds as electron acceptors Nitrate respiration Suphate respiration

IPCC

Intergovernmental Panel on Climate Change International body for assessing the science related to climate change. The IPCC was set up in 1988 by the World Meteorological Organization (WMO) and United Nations Environment Programme (UNEP) to provide policymakers with regular assessments of the scientific basis of climate change, its impacts and future risks, and options for adaptation and mitigation.

IDH hypothesis

Intermediate Disturbance Hypothesis 1. Low diversity - only opportunistic species 2. High diversity - both opportunistic and climax species 3. Low diversity - only climax species (climax species = late-successional species)

Iron (Fe)

Iron is only required in trace amounts however, it is still a limiting nutrient in certain regions -> HNLC regions: high-nutrient, low-chlorophyll Iron is introduced to the ocean by means of e.g. rivers and winds carrying dust (e.g. Saharan dust) -> these vectors are largely absent in HNLC regons

rivet hypothesis

It is a theory that entails about the conditions of ecosystem wherein a significant loss of a certain species affects the functions and diversity of an ecological community.

normal imaging vs multi/hyperspectral imaging

It's all about spectral resolution - A regular camera measures light at three wavelengths (RGB) - -> The combination of these yield the color we perceive - Multispectral imagers typically measure light at 5-15 wavelengths - Hyperspectral imagers typically measure light at 100-300 wavelengths = more color information, distinguish things in a more percise manner, classify things based on light

What is antarctic krill?

Krill are small crustaceans of the order Euphausiacea Krill are considered an important trophic level connection - near the bottom of the food chain - because they feed on phytoplankton and (to a lesser extent) zooplankton, converting these into a form suitable for many larger animals for which krill make up the largest part of their diets. It is a key species in the Antarctic ecosystem and is, in terms of biomass, probably the most abundant animal species on the planet

Lipids

Lipids are major energy sources for animals, major component of cell membranes, and have many other biological functions.

How does feeding rate depend on food density?

Low food density: - consumers are searching for food most of the time Double the food density: - approx. double the feeding rate High food density: - consumers are processing for food most ot the time Increase food density even more: barely an increase in the feeding rate

best time for harvest II?

MSY in many real marine populations closer to K/3 (theoretically K/2)

Recruitment hypothesis

Many hypotheses have been launched to explain the large natural variation seen in the recruitment to fish stocks 4 most important: - Starvation hypothesis: If there is not enough planktonic food in the sea, larval fish mortality will increase and few, if any, will survive to become adults - Predation hypothesis: Predators, including larger fish and some carnivorous zooplankton, may consume large numbers of both larval and juvenile fish. Heavy predation results in few young surviving to become adults. - Advection hypothesis: Physical oceanographic processes transport young fish away from their nursery areaseto unfavourable environments, where they die - Growth hypothesis: Based on the consequences of fish growth being inhibited by either biotic (e.g. food) or abiotic (e.g. temperature) factors.

Metabolic rate, whale vs bacteria

Metabolic rate ~= 3/r gills and lungs compensate bc they increase surface area

Specific metabolic rate

Metabolism/Biomass ~ Surface/Volume ~ 4*Pi*r^2/(4/3)*Pi*r^3 ~ = 3/r Metabolism/Biomass is the SPECIFIC METABOLIC RATE = 3 / r *r = appox. radius

Microorganisms

Microorganisms are very important functional components of the marine ecosystem most of the PS (PP) is undertaken by phytoplankton, which are microorganisms the majority of the respiration is undertaken by bacteria and other microorganisms

Which oceans are considered mesotrophic?

Most of the oceans, average

Bioenergetics example

Mytilus edulis

Nitrogen

Nitrogen is most commonly the limiting nutrient - crucial for generation of amino acids and protein metabolism - the most common form: NO3^- (nitrate)

NDVI

Normalized Difference Vegetation Index, an example of the utility of high spectral resolution imaging

NEAC

North East Arctic Cod stock - presently a very productive stock -> annual quota tripled during last decade - much larger areas of suitable (warm) nursery habitat for young cod resulted from general warming of Barents Sea -> contrinuting to higher productivity of NEAC

Commercial fish stocks that collapsed in the 20th century

Norwegian Spring Spawning Herring (NSSH) Newfoundland Cod (NF Cod)

NSSH

Norwegian Spring-Spawning Herring stock - collapse of NSSH stock by mid 1960s - strict catch regimes followed -> proper stock management policies to bring back natural stock population of NSSH

Distinction heterotrophs - autotrophs

Not always that easy, i.e. a type of tropical coral reef is heterotroph (eating small animal / fish) but also has the possibility to fix carbon. Many heterotropic organisms also have autotrophic structures still embodied (?)

Hydrothermal vents

Occur in regions of high levels of tectonic activity such as mid-ocean ridges - A rich, flourishing community has been discovered in the last 40 years (oasis of the deep sea) - Hot magma chambers; waters above 100ºC - Primary production is provided by chemosynthesis of extremophile archae and bacteria

Oil spill

Oil in water affects plankton, nekton, (incl. fish), aquaculture, birds and marine mammals Oil on the beaches affects coastlines, marinas, freshwater production and seabirds and other animals that live by the sea. • Gulf of Mexico 2010

Nocturnal migration (diel vertical migration)

One migration cycle per day, normally migration up just after sunset and down at or before sunrise. The most common migration pattern

Measuring Disturbance

One-variable index: - Variation in the sole occurrence of one particular species has often been used to describe the effects of disturbances. (indicator species) - However; this approach does not reveal changes in the very structure of the society which might result from the variation in one or a few species. - In most cases the effects of human activity are not species-specific, but may have very different effects on the various components (functions) of the society.

Inverse migration (diel vertical migration)

Opposite of nocturnal migration, migration to surface waters during the day and down to deeper layers in the night

Phosporus

P may occasionally be limiting - crucial for generation of membranes and energy metabolism - the most common form: HPO4^2- (hydrogen phosphate)

Allometric relationships methods

P/B-ratio depends on size and species ! (P= prodcution, B= biomass) [INTRAspecific] - small individuals grow relatively rapid [INTERspecific] - small species have a relatively low metabolic rate - gestation time of mammals increases with maximum size of a species - length at first reproduction increases with maximum size of a species - von Bertalanffy growth rate decreases with body size

What is the most important plankton group in pelagic systems?

Pelagic ciliates -> dominan in many environments -> difficult to bring into culture Strombidium sp. Strobolidium sp. Strombilidium sp. Entodinium sp.

Primary production: Phytoplankton vs. macroalgae

Phytoplankton productivity is much less than that of microalgae per unit area. But: on a global scale, total phytoplankton productivity is far greater than that of microalgae

Phytoflagellates

Phytoplankton; organism that have flagella (use for vertical migration, can not move against current) and have chlorophyll and are capable of photosynthesis;

Main classification of marine organisms based on their habitat

Plankton - organisms floating passively in water masses Neuston - organisms associated with the ultimate water surface Nekton - organisms swimming actively in water masses Benthos - organisms associated to the bottom/sea bed

Ecolabelling

Product marketing which enables consumers to make milieu choices -> urges industry to take part voluntarily in sustainable developement

P/B of small organisms

Production to biomass ratio - P/B closely related to body size (bc. growth and mortality influence are correlated to body size and influence P/B) - small organisms have a high P/B - large organisms have a small P/B --> also valid within species: young cohort higher P/B than old cohort

Where are the hotspots in global primary production?

Rainforests, boreal forests and continental shelves Terrestrial and aquatic production equal

Oil Exploration

Release of hydrocarbons and drilling mud from drilling platforms affects the surrounding seafloor considerably. The effect is seen as a gradient out from the platform, some places out to 100 meters, but in the North Sea up to 6 km

Tubeworm Riftia

Riftia does not have a mouth or a digestive tract (not filter feeders) Trophosomes (organs) where symbiotic chemosysthetic bacteria grow. It has a plume (gills) for gas exhange and a special hemoglobine for H2O, which avoids toxicity.

Simple trophic-dynamic model to predict production (for a trophic level)

Ryther used this

Tubeworms

Sea animals without a mouth or stomach. Bacteria live inside them and make food that they share.

What are seasonal patterns in the phytoplankton mainly related to?

Seasonal patterns in the phytoplankton are mainly related to changes in light, nutrient, salinity and temperature Dominance of specific species ( so-called 'phytoplankton blooms') at different times of the year

Which oceans are considered eutrophic?

Shallow oceans (near coast) - river run-ins - well mixed (spring / fall)

How to sample the deep sea?

So far, only 1 millionth of the sea floor has been sampled (10 Munkholm islands to total Norway land). Before 1950 - sampling was from oceanographic vessels - Nets, box cores and bottom sleds and trawling. Research submersibles (manned - experiments) Unmanned ROVs (tows or cameras) Underwater televisions and cameras Robotics Acoustics

Which techniques and assessment criteria has been introduced to better include functional diversity:

Taxonomic diversity (D) "The average path length between every pair of individual organisms identified from within a sample" Taxonomic distinctness (D*) "The average path length between every pair of individuals, ignoring those between individuals of the same species"

Suphate respiration

Sulphate, thiosulphate and elemental sulphur are used by sulphur reducing bacteria as electron acceptors - sulphide or hydrogensulphide are produced (Schwefelgeruch) - many of the products of anaerobic respiration are toxic (i.e. H2S)

What determines the metabolic rate of an organism?

Surface of an organism rather than biomass (volume)

John Ryther's 3 provinces

THE OPEN OCEAN - 90 % of ocean surface - PP of 50 g C / m2 * yr - ecological efficiency of 0.1 - 5 trophic steps of the food web (6 trophic levels) COASTAL WATERS - < 180 m depth, including offshore regions of comparable productivity - 9.9 % of ocean surface - PP of 100 g C / m2 * yr - ecological efficiency of 0.15 - 3 trophic steps (4 trophic levels) UPWELLING SYSTEMS - 0.1 % of ocean surface - PP of 300 g C / m2 * yr - ecological efficiency of 0.2 - 2 trophic steps (3 trophic levels)

Bioluminescene

The ability to produce light by a chemical reaction within an organism. - 90% of mesopelagic organisms produces bioluminescence. - They can produce the light themselves or through symbiosis (bacteria) or through photophores (glandular organ) - For a reaction to occur, a species must contain luciferin, a molecule that, when it reacts with oxygen, produces light - Advantages: match the dim light (blue-green) from above (countershading), communicate and attract mates, defense mechanism, use light to see and prey

Damming

The building of the Aswan dam resulted in a temporary decline of Mediterranean fisheries. It is assumed that the reduced transport of phosphorous during dam construction eventually was more than compensated by increased supply from water plants downstream after the building of the dam.

Zonation

The change of organisms over cm to meters, or over larger distances Strong zonation is normal in the littoral zone, weaker in open waters Basis for defining benthic and pelagic zones

Example of model prediction (simple trophic-dynamic model to predict production)

The diagram shows probable effects of energy transfer within an ecosystem. 10'000 * 1 would be productivity for no trophic change (=PP) One unit of mass is added to the 5th trophic level (humans) for every 500'000 units of equivalent radiant energy input available to the producers (algae). This value is based on a 2% efficiency of transfer of radiant energy by algae and 10% efficiency at all feeding levels.

PS- and detritus-based food chain

The dual food chain, showing the two starting bases: photosynthesis (the green ellipse) and organic detritus (the red ellipse). The detritus-based food chain can start from bacteria (capable of consuming both POM and DOM) or other organisms (consuming POM). Arrows from "metabolism" boxes to the detritus pool represent excretion, exudation, and sloppy feeding

Life cycle of marine fish

The eggs may be pelagic or benthic, while the early development stages (larvae and youngs) often have a pelagic stage during which they depend on food in the free water masses.

Equilibrium of dissolved inorganic carbon in sea water

The equilibrium in the system is primarily governed by acidity (pH), temperature and salinity pH 8.1 to 8.3 -> 90% inorganic carbon occurs as HCO3^- - some algae can use HCO3^- directly by converting it into CO2

Why is the timing of fish hatching and the spring bloom of planktonic prey organisms important?

The freshly hatched larvae depend on the planktonic algae as prey if they are hatching too early or late --> mismatch

Trophic level

The group of organisms which feed on the same food items, have the same feeding habits

Why is the ocean blue?

The ocean is blue because water absorbs colors in the red part of the light spectrum. Like a filter, this leaves behind colors in the blue part of the light spectrum for us to see. The ocean may also take on green, red, or other hues as light bounces off of floating sediments and particles in the water. Most of the ocean, however, is completely dark. Hardly any light penetrates deeper than 200 m, and no light penetrates deeper than 1000 m.

Trophic transfer

The transfer of materials and energy from one trophic level to levels above

Mesopelagic zone

Twilight zone - it lies below the photic and above the aphotic zone (ca. 200-1000 m) - starts where only 1% if incident light reaches (dim light but not enough for PS) - feeding depends on the organix material that is produced on the surface layers of the ocean and sinks to the deep - life much less abundant

Measuring secondary production

Two components: 1. Somatic production: tissue; muscle, brain, etc. Includes body parts lost and regenerated 2. Gonad production: Reproductve tissue: eggs and sperm

Twilight migration (diel vertical migration)

Two migration cycles per day, normally migration up just after sunset, down during the night, up again just before sunrise, and down during the early day

Hypothesis testing

Type I error: To conclude with difference (reject H0, accept HA) when there in fact is no difference. Type II error: To conclude with no difference (accept H0) when there in fact is a difference. [the null hypothesis at test (H0)is usually that there is no difference between groups, and the alternative hypothesis (HA) is that there is a difference]

UNFCCC

United Nations Framework Convention on Climate Change - international environmental treaty negotiated at the Earth Summit in Rio de Janeiro from 3 to 14 June 1992, then entered into force on 21 March 1994. - focuses to stabilize greenhouse gas concentrations in the atmosphere at a level that will prevent dangerous human interference with the climate system.

Greenhouse gases

Water vapour Carbon dioxide Methane Nitrous oxides CFCs

Oxygen concentrations

Water: 10 ml O2/L Air: 210 ml O2/L oxygen needed in heterotropic aerobic organisms (i.e. animals) to oxidize glucose

Handling time

When "preparing" the food, you're not looking for more food. (When Spongebob is milking the jellyfish, he can't catch more)

Norwegian Sea has a strong seasonality, how does it look like?

Winter <20 [mg C/m2 d] Spring 300-500 --> dominance of diatoms Summer 200-350 --> dominance of coccolithophorids, dinoflagellates and other flagellates Autumn <250

Is biodiversity a meaningful term for microorganisms?

Yes, biodiversity is a meaningful term for microorganisms! But.... Results for microbes and macrobes cannot easily be compared - The species-term is not very relevant for microbes, only the function-term, whereas species and higher taxa is most commonly used for macrobes - There are traditionally fewer scientists working with microbe than macrobe diversity at universities and research institutions, so far

Are PP processes fluctuating?

Yes, constantely because they are governed by light, nutrients and water column properties because satellites have short revisit times (1-3 days), they are good for monitoring large scale dynamic systems like the ocean

Holo-plankton

Zooplankton (heterotroph) that spend their entire lives as plankton i.e. Virus Bacteria and Archaea Protozoa (Copepods, Krill, Cladocera, Amphipods) Gelatinous pl. (jellyfish) and more

What controls secondary production?

[BOTTOM UP CONTROL] secondary production is controlled by primary production [TOP DOWN CONTROL] primary production is controlled by grazing (i.e. secondary production)

Bioconcentration

[Bioaccumulation] occurs within an organism, where a concentration of a substance builds up in the tissues and is absorbed faster than it is removed. Bioaccumulation often occurs in two ways, simultaneously: - by eating contaminated food - by absorption directly from water. --> second case is specifically referred to as [bioconcentration]. --> Eg. Mussel watch program

Adaptations of twilight animals

[ZOOPLANKTON] - some migrate and conserve energy to foray (=Streifzug), others are filter feeders [FISH] - small size - large mouth and pointed teeth - unspecialized diet [MIGRATING FISH] - strong muscles and a swim bladder filled with fat or gas (non migrators: conserve energy/flabby muscles, lost swim bladder, soft bones) - large and sensitive eyes - camouflage (transparent or reddish color), reduced silhouette and bioluminescene - well developed gills, hemoglobin or inactive in oxygen minimum zones

Cohort

a cohort is a group of animals of the same species, identfied by a common characteristic, which are studied over a period of time

Keeling Curve

a graph which plots the ongoing change in concentration of carbon dioxide in Earth's atmosphere since 1958

diffusive boundary layer (DBL)

a layer surrounding each cell or surface in water which restricts molecular diffusion (of nutrients into the cell) - the thickness of DBL is critical for the rate of nutrient diffusion - a large surfacearea to volume ratio (SA) enhances diffusion in small cells

Morphospecies

a taxonomic species based wholly on morphological differences from related species

Marine snow

aggregated detritus particles

carbon assimilation efficiency I

another important ecological term (besides carbon growth efficiency) -> defines the digestibility of the food Assimilation (A) = G + R = I - F The assimilated food is the food taken up in the intestine, incorporated in tissues I: Food intake, consumption, ingestion G: Growth, biomass production R: Respiration F: Defecation, production of faeces, zero for bacteria

Disturbance definition

any time-limited event which tears up existing ecosystems, societies or population structures and changes resources, substrate availability or the physical environment. boradly divided into natural and anthropogenic.

Examples for primary producers

aquatic (benthos): 1. Algae (micro- & macroalgae) 2. Seed plants (seagrass) 3. Bacteria (e.g. cyanobact) aquatic (pelagic): 1. Algae (microalgae) 2. Bacteria (e.g. cyanobact) --> here no macroalgae / seagrass because it's too deep terrestrial: multicellular organisms (e.g. vascular plants)

What determines the mixing depth in spring?

as spring progresses towards summer, the sea surface is increasingly warmed by the sun - warm water is less dense than cold water, consequently a warm surface layer forms - the warm surface layer is separated from the cold deeper water by a thermocline - little water exchange occurs between the warm surface layer and the cold deeper water, which means that the thermocline effectively determines the phytoplankton mixing depth - layer formation caused by temperature differences is termed "thermal stratification"

Phytoplankton

autotrophic prokaryotic or eukaryotic algae that live near the water surface where there is sufficient light to support photosynthesis. Among the more important groups are the diatoms, cyanobacteria, dinoflagellates and coccolithophores.

Bacterioplankton

bacteria and archaea, which play an important role in remineralising organic material down the water column (note that prokaryotic phytoplankton are also bacterioplankton).

Standing stock

biomass present in an ecosystem at a given time

Osteichthyes

bony fish, diverse taxonomic group. - many bony fish have pelagic (planktonic) eggs --> after developement from egg to larvae they may become nektonic - in some species, the juveniles settle on the bottom --> also the adults of the species show a demersal or semi-demersal life (e.g. cod)

micronutrients in the ocean

boron (B), copper (Cu), iron (Fe), manganese (Mn), chlorine (Cl), molybdenum (Mo), zinc (Zn), silicate (Si) - elements are used in very small amounts exceptions: - (Si) can function as a macronutrients (i.e. for diatoms, radiolarians, slicoflagellates) ->can be limiting element (i.e. end of diatom spring bloom) - (Fe) can be a limiting microelement (HNLC regions)

MSC

certified sustainable seafood fish are caught at levels that allow fish populations and the ecosystems on which they depend to remain healthy and productive for the future

Norway / EU fish stock management: mooore issues (III)

cooperation bad no practical control cooperation only few exchanges of statistics, quotas and controls too little emphasis on the management of coastal fish stocks

World's upwelling regions (Ryther, production)

covers 0.1 % of the ocean surface typical annual production: plants 300 [g C / m2] fish 36 [g C / m2] transport of deep-water to surface --> high nutrient supply to surface waters --> even though upwelling areas account for only 0.1 % of ocean surface, they support 50 % of the world's fish production

World's Coastal Regions (Ryther, production)

covers 10 % of ocean surface typical annual production: plants 100 [g C / m2] fish 0.34 [g C / m2] variable transport of deep water to the surface --> low or high nutrient supply to surface waters, variable

World's Open-Ocean Regions (Ryther, production)

covers 89 % of the ocean surface typical annual production: plants 50 [g C / m2] fish 0.0005 [g C / m2] low / very low transport of deep-water to surface --> low nutrient supply to surface waters

morphospecies species concept

defined by morphological characteristics; individuals that share many morphological features are considered one species

Red tides are caused by

dinoflagellate blooms

Discrete vs continuous population dynamics

discrete: - follow pop over time intervals - often used when reproduction or mortality is nearly a discrete event continuous: - follow a pop continuousely - often used when reproduction is more or less a continuous event

groups based on carbon/energy sources

energy source / carbon source -> type (example) [AUTOTROPHS] light / CO2 -> Photoautotroph (most phytoplankton, plants [=oxygenic], green bacteria, purple bacteria [=anoxygenic]) chemical / CO2 -> Chemoautotroph (iron-oxidizing bacteria) [HETEROTROPHS] light / organic compounds -> Photoheterotroph (green bacteria, purple nonsulfur bacteria) organic compounds / organic compounds -> Chemoheterotroph (fermentative bacteria, animals, fungi, bacteria) *** mixotrophic: light/CO2 or organic matter (some phytoplankton) auxotrophic: light/CO2, but with requirments of specific essential components

Eco-clines are:

examples: #Light #Nutricline - changes in nutrients #Pycnocline - oxygen #Thermocline - temperature #Halocline - salinity

EEZ

exclusive economic zone; an area of coastal water and seabed within a certain distance of a country's coastline, to which the country claims exclusive rights for fishing, drilling, and other economic activities. normally 200 nautical miles

Experimental design

experiments must be planned so that the data obtained are suitable for the relevant statistical procedures and tests

Stock assessment

factors which increase the total biomass of a stock are - recruitment (# offspring) - individual growth rates - natural and fishing mortality reduce the total biomass --> in overexploited stocks, the fishing mortality is too high relative to recruitment and growth

Gonad

female or male reproductive organ that produces sex cells and hormones; ovary or testis

two stages of decomposition

first step: - takes place outside bacterial cells

What influences PP?

for phytoplankton - light - inorganic nutrient supply - physical properties of the water column -> these factors also apply to e.g. kelp forests and seagrass beds, but the latter plays a less important role

Physical properties of the water column

for phytoplankton, the physical properties of the water column are also very important for productivity (besides light and nutrients) Water column properties can, however, be considered a secondary factor as they in terms of primary production strictly relate to light and nutrient exposure two terms are key: Compensation depth Critical depth

Michaelis-Menten model

function of 'nutrient uptake rate' (v) with 'nutrient concentration' (S) (Vmax = maximum uptake rate; Km= half saturation constant)

Mycoplankton

fungi and fungus-like organisms, which, like bacterioplankton, are also significant in remineralisation and nutrient cycling

Ocean Productivity

great areas of the ocean are still considered as biological deserts (between euphotic zone and deep sea) - metabolism of the deep ocean is primarily supported by the transport of organic material out ot the euphotic zone - ca 90% of open ocean respiration occurs in the epipelagic zones (0-200 m)

HABs

harmful algal blooms - some algal species are toxic - these species ma form HABs under certain conditions -> nutrients -> temperature -> wind / water mixing - mostly dinoflagellates - HABs are frequently called "red tides" due to their appearance

How do you distinguish between high light- and low light-acclimated cells?

high light acclimated cells are highly capable of acclimating to changing light conditions "real time" - alterning concentrations of light harvesting pigments - production of photo-protective pigments - stacking of pigments low light acclimated cells can not acclimate that well

What does RUBISCO need to function?

high supply of CO2 carbon concentrating mechanisms (CCMs) maintain a high CO2 level inside the cells where RUBISCO is situated

Grouping of zooplankton based on life cycle

holoplankton -> permanent plankton meroplankton -> temporary plankton, one or few states resides in the water masses, normally larval stages

Holling Type 2 functional response

how feeding rate depends on food density

growth efficiency

important term in resource oriented research and management, for example in models for prediction of fish production (i.e. trophic yield on organism level) For carbon: I = G + R + F For N and P: I = G + E + F I: Food intake, consumption, ingestion G: Growth, biomass production R: Respiration (only for carbon) F: Defecation, production of faeces, zero for bacteria E: Excretion (not for carbon, for all other elements)

Nutrients supply for marine plants (schematic)

in addition to carbon, plants need to take up other elements in order to synthetize macromolecules (e.g. proteins, nucleic acids)

nutrients and PP

in addition to light, photosynthetic organisms require certain essential nutrients for growth Carbon, oxygen and hydrogen (rarely an issue) Nitrogen, Phosphorus (usually the limiting factor) Sulphur Silicon, Iron (limiting under special circumstances)

How does light penetrate water?

in clear water, blue light penetrates deepest in water containing a lot of colored dissolved organic matter (cDOM), which strongly absorbs blue light, bluegreen-green light penetrates deepest

Secondary production =

increase in reserves + somatic biomass + gonads

Mixotrophy

interface between autotrophy and heterotrophy - mixotrophs can switch from photosynthesis (autotrophy) to an uptake of particulate organic matter (heterotrophy) - many phytoplankton species have shown to be able to ingest particulate organic matter to meet part of their nutritional requirements - some marine organisms (e.g. molluscs, ciliates) retain chloroplasts which they ingested when grazing on photosynthetic organisms -> the chloroplast is then used as an additional energy source --> example: the ciliate Mesodinium rubrum

Biogeography

is the study of the distribution of species and ecosystems in geographic space and through geological time Phyto-Geography = the branch of biogeography that studies the distribution of plants Zoo-Geography = the branch that studies distribution of animals

Blob

is unusal warming over large extend with great strength and enivronmental impact. -> more a local phenomenon

Thermal stratification

layer formation caused by temperature differences (in the ocean)

Light and PP

light = most important factor for Photosynthesis and PP light determines both the rate and the extent of photosynthetic activity

Hypoxic

low oxygen

Biomass quantity of the main heterotrophic plankton groups in Norwegian coastal waters, May to October?

main heterotrophic plankton groups in Norwegian coastal waters: 1) Copepods 2) Bacteria 3) Ciliates 4) Heterotrophic flages (

Urocordata

make nets, like spider catch small food down to bacteria size often, but not in high densities

Seasonal succession of phytoplankton species

many species are in the watercolumn for just a specific, short time. in the other time they sink to bottom (and wait until better conditions for them) or they rest somehow (=not visibal in the water column)

MSY

maximum sustainable yield (MSY) = maximum long term yield (MLY) carrying capacity and replacement lines for fishing pressure the growth rate is at maximum at K/2!

Best time for harvest?

maximum sustainable yield: -> the size of a natural population at which it produces a maximum rate of increase, typically at half the carrying capacity. -> the maximum level at which a natural resource can be routinely exploited without long-term depletion. -> aims to maintain the population size at the point of maximum growth rate by harvesting the individuals that would normally be added to the population, allowing the population to continue to be productive indefinitely. -> under the assumption of logistic growth, resource limitation does not constrain individuals' reproductive rates when populations are small, but because there are few individuals, the overall yield is small. -> at intermediate population densities, also represented by half the carrying capacity, individuals are able to breed to their maximum rate. At this point, called the maximum sustainable yield, there is a surplus of individuals that can be harvested because growth of the population is at its maximum point due to the large number of reproducing individuals.

14C tracer method [carbon and oxygen flux measurement]

measuring carbon assimilation in phytoplankton with a tracer molecule -> used to estimate PP pro: straight forward and direct measure contra: gross and net pp can not be clearly distinguished use of radioisotopes requires special procedures

Winkler Method [carbon and oxygen flux measurement]

measuring dissolved oxygen (DO) in the water -> used for PP estimation -indirect measurement -very common in the past pro: highly accurate even at low DO concentrations contra: prone to human error, time consuming, not suitable for field

18O tracer method [carbon and oxygen flux measurement]

measuring gross oxygen production -> used to estimate PP 18O is added as tracer not very commonly used yet pro: allows quantifying light dependent oxygen cycling, applicable also in oligotrophic waters contra: very expensive

Where does metabolism of marine systems happen?

metabolism: the chemical processes that occur within a living organism in order to maintain life. Most metabolism of marine systems is associated to organisms <1 µm Very little happens in size classes >10 µm - Almost all metabolism occurs in pico-plankton (<2µm) - Some in nano-plankton (2-20 µm) - Little in larger plankton - Next to nothing in nekton and larger animals, e.g., vertebrates and mammals

What is the best rate / duration of upwelling combination for optimal production?

moderate rates of upwelling for long duration (8months or longer) provide the ultimate co,bination for large fisheries the highet rates of upwelling remove plakton, or fishfood from surface waters plankton becomes diluted, food is reduced ->intermediate rates become optimal with intermediate upwelling rates, phytoplankton also become bigger, why so is difficult to understand

Discharge of contaminants

most important contaminants: - radionucleotides and organic compounds from energy plants and the industry -> PCB (polychlorated biphenyls), shown to reduce hatchability in bird eggs, while toxic mercury accumulates in bird's feathers. - heavy metals generally accumulate and have toxic effects high up in the food chain (top predators like fish, birds, polar bear), while fat-soluble dioxins have toxic effects e.g. through mother's milk in mammals. - different flame-inhibitors ("Brandschutzmittel") are shown to give hormonal disturbances in fishes, and may lead to disturbances in sexual expression ("gender benders"). - radioactive compounds from nuclear plants have leaked to the sea and led by ocean currents long distances in the East Atlantic. -> Leakages from the English nuclear plant Sellafield have been traced in plant- and animal tissues even in the inner parts of Norwegian fjords Currents of the ocean make contaminants very mobile. i.e. dioxins have reached alarming concentrations in polar mammals.

Phanerozoic (Phanerozoikum)

nicht auswendig lernen!

primary inorganic nutrients that are needed (macronutrients)

nitrogen (N), phosphorous (P), potassium (K), calcium (Ca), magnesium (Mg), sulphur (S)

Why is the availability of carbon in a plankton / nekton community higher than the primary production?

organic cycling - dead organic matter can be taken up in the food chain several times before it is respired some parts of the carbon uptaken will be "lost" through shit or death before respiration will mineralize it

Benthos

organisms associated to the bottom/sea bed

Neuston

organisms associated with the ultimate water surface

Plankton

organisms floating passively in water masses

Nekton

organisms swimming actively in water masses

What is a functional ecological group?

organisms that have similar functions in the ecosystem are assigned to the same functional group i.e. thise that eat same food, have similiar size, eaten by same predators the simplest functional group = the species assigned to a trophic level in a food chain

what is tactical phytoplankton?

phytoplankton may adjust their behavior to exploit the environmental conditions as efficiently as possible -> when nutrients are limited in the surface layer and light is plentiful it may for instance be beneficial to be situated as close as possible to the nutrient-rich deep waters phytoplankton can "decide" where they want to be. The bottom layer in the picture shows the best combination of ligh and nutrient availability

How is light harvested by photoautotrophs?

pigments terrestrial plants rely on two pigments for light harvesting: chlorophyll a and b --> this gives good absorption of blue and red wavelengths the pigment composition of algae (e.g. phytoplankton) is much more diverse! --> this is likely an evolutionary adaption to aquatic environments, where light is a scarce resource (beneficial to be able to use more of the visible light spectrum 400-700 nm, especially bluegreen wavelengths which penetrate deepest when the water contains cDOM)

match-mismatch hypothesis

principal for starvation-hypothesis the idea that population regulation in many fish is determined in the early juvenile stages by food supplies, so that if eggs hatch at the same time that food is abundant, many will survive, but if eggs hatch when food is scarce, many will die

How to calculate P/B (for a 1 year time period)

production / mean population mass

Trophic yield (Yt)

production at trophic level i+1 / production at trophic level i

Yield

production rate the yield is the amount of the product which may be removed from the ecosystem so that it is capable of recovering in one year

P/B

production to biomass ratio production/standing stock = how much biomass is produced by the standing stock of biomass e.g. kg of salmon biomass produced per kg of salmon present per year kg / kg. yr -> kg streichen -> 1/yr => 1 kg per year both P and P/B are growth rates!

Allometric relationships

relationship of body size to shape, anatomy, physiology and finally behaviour -> used to estimate/calculate secondary production, when there are no recognizable cohorts

Yield: relative vs absolute meaning

relative meaning: e.g. amount of biomass produced per amount of food given absolute meaning: e.g. amount of biomass harvested this year

SST

sea surface temperature

Silicon

silicon is crucial for certain phytoplankton groups - particularly diatoms -> diatoms are responsible for nearly 50% of the marine PP -> they generate frustules - or cell walls- of silica -> typically bloom during spring when nutrients (including silicon) are abundant due to mixing of the water column during winter

PEG Model Oligotrophic

single algae boom

Zooplankton

small protozoans or metazoans (e.g. crustaceans and other animals) that feed on other plankton. Some of the eggs and larvae of larger nektonic animals, such as fish, crustaceans, and annelids, are included here.

Secondary production consists of two components. Which ones?

somatic production -> production of tissues (i.e. muscle, brain, skin, shell etc) gonad production -> reproductive tissue (i.e. sperm, eggI somatic production more interesting because it represents the quantity of matter and energy that is available as food for the next trophic level (i.e. natural predators, human consumption)

Selective feeding

some prey organisms are preferred over others

Plankton vs Nekton; what decides?

somethimes hard to draw a line.. example. are jellyfish plankton? they swim, but also float with water currents -> yes, jellyfish are classified as zooplankton

Bioenergetics

study of the transformation and transduction of energy in living organisms

Proxies

substitute recorders for past climate conditions (non instrument) - pollens - foraminifera - tree rings - corals - ice core - sediment cores

Heritability

the ability of a trait to be passed down from one generation to the next

Functional biodiversity

the biological and chemical processes such as energy flow and matter recycling needed for the survival of species, communities, and ecosystems Structural functionality of ecosystem

Critical depth (physical properties of water column)

the depth where the daily photosynthetic carbon production in the overlying water column equals the column's daily respiratory carbon losses (net production = 0) - mixing depth shallower than the critical depth: net phytoplankton growth - mixing depth deeper than the critical depth: net phytoplankton reduction

Compensation depth (physical properties of water column)

the depth where the photosynthetic rate equals the resiration rate (also the bottom of the euphotic zone)

Ecosystem biodiversity: function vs components

the function of an ecosystem is more important than the components

Biological pump

transport of organic carbon and nutrients from the surface ocean to the deep ocean which are then upwelled to the surface remove CO2 from atmosphere to marine sediments

Yt

trophic yield, efficiency of trophic transfer 5-20 % for carbon in marine pelagic systems (10 %) 30-40 % for N and P Lowest values in nutrient poor (oligotrophic) open ocean, highest in nutrient rich coastal waters

UHI

underwater hyperspectral imaging for even higher resolution than from sattelites, airplanes

Trophic-dynamic model

used to predict theoretical production on given trophic level trophic transfer: The transfer of materials and energy from one trophic level to levels above

Heteroptrophic marine mero-plankton

very diverse Larval stages of: - Crustaceans - Fish - Shellfish - Polychaeta - more

Dynamic energy budget model

very important! general framework for any secondary producer (dissipation = "Verschwendung")

nLW

water-leaving radiance. means the measured color of an algae

Euphotic zone

where light is sufficient for PS to occur approx. 0-200 meter depth

Why do eukaryotic microorganisms bloom / have high seasonality?

winter -> many nutrients spring -> + sun = bloom watercolor changes

North Sea Fisheries

ÖRESUND and KATTEGAT - long history - since 1932, almost total ban on towed fishing gears in the Öresund but not in the Kattegat - both the Öresund and the Kattegat show strong vertical stratification with a brackish upper water layer, and a heavy, oceanic water layer underneath - areas show typical seasonality in terms of thermal regime - the productivity of the ecosystem is fairly high due to the inflow of nutrients and beneficial temperature conditions - fish community similar to those in the rest of the North Sea - most commercial demersal fish stocks are recognized as commercially extinct except for sole and plaice

Phytoplankton overview

• Photosynthetic organisms in the plankton show a high variability in size and forms • Prokaryotic microorganisms: cyanobacteria, prochlorophytes → contribute to a high percentage to the primary production in open oceans (but still under-investigated so far) • Eukaryotic microorganisms: diatoms, phytoflagellates → bloom formation, high seasonality e.g. in temperate oceans

upwelling regions

→ high primary production due to an upwelling of cold, nutrient-rich deep water → ocean colour: brown, olive (dominance of diatoms) → high secondary production (high fisheries yield) → several coastal regions are characterized by an introduction of cold, nutrient-rich deep water to the surface

Where are most upwelling regions located and what are the effects of upwelling?

→ west coasts of continents → ocean colour: brown, olive (dominance of diatoms) → high secondary production (high fisheries yield)