Eco Final

Gamma Diversity

"geographic-scale species diversity" = total number of different species in all ecosystems

CE will be higher in what type of ecosystems (independent of primary production rate)

-Ecosystems dominated by nutrient-rich plants that have few structural tissues. -Thus, ecosystems whose plant biomass turns over QUICKLY (e.g., algal ecosystems) will have higher consumption efficiencies than ecosystems whose biomass turns over slowly (e.g., forests)

2 hypotheses that drive species richness (aka alpha diversity)

1. Alpha diversity is determined by gamma diversity. Each time space in a site opens up, it may be settled by any colonist arriving from the regional species pool, the size of which is determined by rates of speciation and extinction. 2. Alpha diversity is determined by local species interactions. Competition for space and other resources, predator/prey dynamics, etc., drive alpha diversity by determining which species can survive at any given site and whether or not a new species can successfully colonize it.

Tolerance

1. Any species arriving on site can establish 2. Other early successional species are Reduced 3. Late succesional species are Unaffected

Inhibition

1. Any species arriving on site can establish 2. Other early successional species are Reduced 3. Late successional are Prevented until existing individuals die, opening space

5 Ecological determinants of biodiversity

1. Area available 2. Temperature 3. Rainfall 4. Immigration/extinction rates 5. Competition 6. Presence/rates of disturbances

Disturbance

1. Discrete event in time that disrupts 2. Ecosystem, community, or population structure 3. Changes resources, substrate availability, or the physical environment

Extinction rate of island

1. Extinction rates increase with more species on island (approaches the number of species in the mainland species pool) 2. Extinction increases with smaller islands (inverse)

3 models of succession after disturbance

1. Facilitation 2. Inhibition 3. Tolerance

Why is studying phylogeography useful? (4)

1. Help identify shared signals of historical events (such as stream captures, glacial cycles and marine transgressions) that contributed to population divergence and speciation in multiple groups. 2. Enhance knowledge of how speciation happens and the assembly of community structure 3. Identify geographic areas of high genetic diversity 4. Identify evolutionary processes which can be included for conservation planning on regional scales

Fundamental evidence for climate change

1. Higher air and sea temperatures near the surface of the Earth. 2. Higher land temperature 3. Cryosphere (snow and ice) melting. Glaciers and permafrost melting 4. Changing precipitation patterns 5. Rising sea levels 6. Ratio of oxygen isotopes in ice cores 7. Variations in tree rings (thicker = faster growth)

Immigration rates to island

1. Immigration rates decline with more species on the island 2. Distance from mainland decreases immigration rate

3 ways disturbances alter community structure

1. Kill organisms 2. Altering resource availability 3. Alter geography

R* rule (3)

1. Level of a limiting resource at equilibrium R* 2. Theoretically over the long run, in a constant environment, the species with the lowest R* will competitively out compete the others 3. In uniform environment a single species should dominate

Factors that limit secondary production

1. NPP (amount of energy available for plants) 2. Ability to find food/food availability

NPP (of ecosystem and individual plant) (4)

1. Net Primary productivity = Difference between the rate at which energy is captured during photosynthesis and the rate at which energy is lost as heat. 2. The rate at which the plant stores energy as biomass 3. NPP (ecosystem) = GPP - Ra 4. NPP (plant) = (m2 - m1) / (t2-t1) = above-ground biomass density at times 1 and 2

Competitive exclusion assumptions (2)

1. No 2 species can coexist in exactly the same ecological niche. 2. If 2 species are using exactly the same resources, one of them is expected to win the competition and to drive the other species to extinction in that location

Technique for measuring NPP of aquatic ecosystems (7)

1. O2 levels are measured at the beginning and end of exposure to light and dark bottles at conditions (light, temperature) of interest 2. Light bottle represents NEP as the O2 produced by photosynthesis is reduced by the amount consumed by respiration 3. Dark bottle represents O2 consumed by respiration (Re) since no photosynthesis can take place 4. Re (daily ecosystem respiration) = (Initial Dissolved Oxygen) - (dark bottle Dissolved Oxygen after 24 hours) 6. NEP (net ecosystem production) = (light bottle Dissolved Oxygen after 24 hours) - (initial Dissolved Oxygen) 7. GPP = Re + NEP

Facilitation

1. Only early successional species can establish 2. Other early successional species are Reduced 3. Late successional are Enhanced

Things that make species accumulation curves inaccurate (3)

1. Sampling error 2. Rare species 3. Too small of area size

Abstract rules for constructing Eltonian biomass pyramid (things that matter)

1. Small, numerous organism as primary producer, eaten by larger less numerous things= inverted because less biomass on bottom 2. Large, sparse organism as primary producer, eaten by smaller more numerous things = Regular because more biomass on bottom

Problems with using only above ground mass to measure NPP (2)

1. Tends to underestimate NPP because biomass in below-ground structures (such as roots) is ignored 2. Biomass lost when plants die or are eaten by other organisms is ignored, because roots and dead or eaten parts are often too difficult to measure.

Why do terrestrial ecosystems have lower trophic efficiencies than aquatic ecosystems? (2 reasons)

1. Terrestrial herbivores have lower consumption efficiencies than their aquatic counterparts. 2. Endothermy in terrestrial ecosystems is less efficient than exothermy in aquatic ecosystems

Island bio-geography predictions (3)

1. The Area effect is stronger on more distant islands 2. The distance effect is stronger for small islands (true for log species number not always for absolute species number) 3. Area effect is reduced for far islands if there are stepping stones

GPP

1. The rate at which solar energy is captured for photosynthesis 2. GPP = Ra + NPP

Island biogeography problems/exceptions (4)

1. Very small islands 2. Does not take evolution into account 3. Assumes every community is at equilibrium (they're not) 4. Not all species are equal

2 Historical determinants of biodiversity

1. Vicariance event - Speciation occurs at the same time as the geologic event and in the same location as the ancestor population because of altered gene flow, etc. 2. Geological event (asteroid impact, mountain range formation, glaciation, continent movement) that results in change of amount of resources available to any particular species

NEP

1.Net ecosystem production 2. NEP = GPP - (Ra+ Rh)

How much has atmospheric CO2 changed over last 150 years?

280 ppm to 380 ppm

How much (in ppm) has atmospheric CO2 increased in last 400,000 years?

280-380 ppm

X vs. Y have 5 of the same species. X has 2 unique species, Y has 2 unique species, Beta diversity is ?

4 (2 from X + 2 from Y)

Resource partitioning

A concept that relates the evolutionary changes in specific resources utilized by species with similar niches, which may or may not refer to the specific selection pressures generated by previous or ongoing interspecific competition. Examples would be species of warblers with similar sizes, shapes, and beak sizes feeding on insects from different parts of the same species of tree

Emergent property (definition)

A property unique to a particular level of organization, which cannot be deduced from simply looking at other levels of organization. Higher scales of organization containing smaller scales (e.g., community containing populations), and smaller scales of organization affecting higher scales of organization.

Succession progresses towards?

A stable climax community; however, because communities are open and affected by external forces, including disturbance, they are rarely (never) in equilibrium

Ghost of competition past

A theory by Connell that attempts to explain the apparent co-evolutionary divergence between two species which may in the past have competed for similar resources, resulting in their present observed character displacement.

Island biogeography assumptions (4)

A. Immigration rate (I) is a function of distance (D) from source area B. Immigration rate (I) decreases as the number of species present (S) increases C. Extinction rate (E) increases as the number of species increases D. E is increases on smaller islands

What limits primary production in aquatic systems? (when compensation depth is low, aka in a lake where light is the same at all depths)

Abundance of nutrients (Nitrogen, Phosphorous, Iron, Silica) because of ability/need to make DNA and do photosynthesis

Invasive species

Alien, exotic, non-native nonindigenous species outside of its natural range; a species that humans have placed into an ecosystem or community in which it does not naturally occur whose introduction causes or is likely to cause economic or environmental harm

Tragedy of the commons

Any commonly owned resource that may be publicly used is susceptible to the tragedy of overuse. Each man is locked into a system that compels him to increase his herd without limit - in a world that is limited. Ruin is the destination toward which all men rush, each pursuing his own interest in a society that believes in the freedom of the commons.

Assimilation equation

Assimilation = Ingestion - Egestion

Ra

Autotrophic Respiration - Conversion/cost of energy it takes to break down glucose (aerobic respiration) conducted by autotrophic organisms, primarily plants, algae, and other photosynthetic organisms

Why is NPP so critical?

Because part of NPP goes to detrital food chain, part goes to grazer/secondary production. It is the max energy that can be used by ecosystem

Intraspecific

Belonging or referring to some ecological variable "Between" the same species

Conspecific

Belonging to the same species

Regulating ecosystem services

Benefits derived from the regulation of ecosystem processes, including water purification, flood control, disease regulation, and crop pollination. - Growing forests that help offset fossil fuel combustion by removing CO2 from atmosphere

If you were to track how the concentration of CO2 in an actively growing forest changes over the course of 24 hours, when would you expect concentrations to rise? When would you expect them to decrease?

CO2 will decrease during the day and increase at night.

N2 and O2 are transparent to both long and short wavelengths, but greenhouse cases like ____, ____ and ____ absorb ________ radiation that is radiated by earths surface and spew it into all directions where it raises the average surface temperature.

CO2, CH4, and H2O, absorb the longwave radiation

How do disturbances like fire help maintain habitat diversity?

Creating patches with distinct characteristics, prevent one type of species from dominating and stopping other types of species from growing

Primary production

Creation of new biomass from inorganic molecules

Albedo

Degree that a planet reflects radiation. 0= dark; 1 = bright

Interference competition

Direct competition, occurs when competing individuals (usually of the same species) directly interact in an attempt to reduce the other's access to resources. A classic example of interference is fighting over food, water, space, or mates.

Cultural ecosystem services example

Ecology students often venture out into local ecosystems to conduct experiments and learn about the natural world

Supporting ecosystem services

Ecosystem processes necessary for the production of all other ecosystem services and include primary production, nutrient cycling, and soil formation - Crop rotation, seed dispersal, etc.

Energy _________ through the ecosystem, matter ____________ through ecosystem

Energy flows Matter cycles

Evenness

Evenness is a measure of the relative abundance of the different species making up the richness of an area.

Interspecific

Existing or occurring between different species

Island equilibrium model explained in words

For any island of area Am and distance from the source area D, immigration rate and extinction rates will approach equality such that I = E, and the number of species on the island approaches a constant S^. There will be a finite turnover rate (T)

Keeping in mind the concept of species turnover, how do you think Erwin used his data on beetle species richness to extrapolate an estimate of tropical arthropod diversity?

He estimated proportion of beetles were specialists. (# of beetle specialists X estimated total number of tropical tree species) = Approximate number of species of beetles.

Rh

Heterotrophic respiration - how much energy or carbon is used for heterotroph metabolism

Allelopathy

Interference competition involving secondary metabolites produced by plants, algae, bacteria, and fungi that inhibits the growth, survival or development of another Ex) Tree of Heaven

Inverted Eltonian biomass pyramid

Inverted: Aquatic ecosystems, primary producer is numerous small algae, eaten by numerous plankton, eaten by less numerous fish = less biomass on bottom than top

How much has global temperature increased in last 400,000 years?

Its varied by about 1 deg C

Allelopathy examples

Juglans nigra, Tree of Heaven

How is NPP measured in oceans/aquatic ecosystems

Measured O2 production in a pair of similar bottles, one transparent (Light Bottle) and the other opaque (Dark Bottle)

If two islands are the same size, the near island will have ________ species at equilibrium. Why?

More Because, for any given number of species on the island, immigration rates will be higher on the near island than on the far island

Herbivores grow most efficiently when the ratios of (C)arbon to (N)itrogen and to (P)hosphorus in their food are ?

Most similar to the C:N and C:P ratios of their own tissues.

What can you conclude if CO2 in the air around a plant is accumulating over time (that is, net CO2 is increasing)?

NPP is negative (i.e. GPP < R) If net CO2 is increasing, then respiration rates are higher than gross primary production rates, which means NPP is negative

Secondary Production

New biomass created from existing organic matter/molecules, as when heterotrophs build new tissue out of the food that they eat, which is expressed as a rate

Why does low signal to noise ratio make things harder to detect?

Noise = variability (i.e "noise" in the data) Trends = signal

Seasonal variation in CO2 concentrations should be greater in the _________ Hemisphere because its land area is greater than the __________ Hemisphere's, peaking in ____ or _____

Northern > Southern, peaking in April or May

Coexistence

Populations of several species that utilize the same limiting resources manage to persist within the same locality

Production effieciency of herbivore equation =

Production of Herbivore / Assimilation of herbivore

Provisioning ecosystem services

Provisioning services include ecosystem goods that are directly consumed by people, including food, fresh water, timber, fiber, medicines - Growing specific trees to cut down

Re

Re (ecosystem respiration) = Ra + Rh

Regular Eltonian biomass pyramid

Regular/fat on bottom: very few massive trees are primary producer, primary herbivore is small numerous insects, insects eaten by larger less numerous birds

Succession

Repeatable change in community composition through time following a disturbance

Trophic Level size/length of chain

Resource availability often determines the abundance of individuals in each trophic level. Similarly, resource abundance often determines food chain length.

What limits terrestrial primary production small scales? at large ones?

Small: Nutrients and light availability Large: Temperature and Precipitation

Phylogeography

Spatial and temporal distribution of gene sequences in populations of a single species, or among closely related species.

Allopatric speciation

Speciation that occurs due to geographical separation

Sympatric Speciation

Speciation that occurs when one part of the species/population tries out a new niche (such as apple flies trying out a new type of apple)

Endemic

Species found exclusively in localized area in the world

Sankey diagram illustrates

Sum of the widths of arrows flowing into plants equals the sum of the widths of arrows flowing out.

How can tragedy of commons explain pollution?

The commons is the broader environment, and the rational actor is the polluter. Polluters choose to pollute because the cost of not polluting tend to be high and incurred by the individual polluter, while the cost of polluting is typically borne by society as a whole

Alpha Diversity

The diversity within a particular area or ecosystem, and is usually expressed by the number of species (i.e., species richness) in that ecosystem

Emergent property are based on

The fact that all scales of organization possess properties that are unique to that scale and that cannot be deduced from properties of other included scales. For example, the nature and strength of interactions among two species of meadow mice cannot be fully explained even with the most sophisticated models of their population dynamics. Thus, many interactions at the community level are emergent properties of communities.

Richness

The number of species per sample is a measure of richness. The more species present in a sample, the 'richer' the sample.

Detection

The process of demonstrating that climate has changed in some defined statistical sense, without providing a reason for that change

Attribution

The process of establishing the most likely causes for the detected change with some defined level of confidence based on what we know happens (ie. you change the chemical composition of the atmosphere, shyt goes down)

Evenness example

The sample from the first field consists of 300 daisies, 335 dandelions and 365 buttercups. The sample from the second field comprises 20 daisies, 49 dandelions and 931 buttercups (see the table below). Both samples have the same richness (3 species) and the same total number of individuals (1000). However, the first sample has more evenness than the second. This is because the total number of individuals in the sample is quite evenly distributed between the three species. In the second sample, most of the individuals are buttercups, with only a few daisies and dandelions present. Sample 2 is therefore considered to be less diverse than sample 1.

Phenology

The seasonal timing of animal and plant life history events, such as reproduction, dispersal, hibernation/dormancy, etc.

Beta Diversity

The total number of species that are unique to each of the ecosystems being compared (aka species turnover)

Wilson and Macarthur

Theory of island biogeography

Effect of warming climate on Generalists

They do fine, they eat flowers that bloom earlier and survive

What kinds of areas would have highest beta diversity?

Two adjacent areas that are very different, such as those that have large differences in elevation, temperature, precipitiation - (microclimates on a mountain) will have species that turnover quickly = high beta diversity

Allopatry

Two organisms, or two populations, or two distinct varieties of species or taxa living in different geographic areas separated by some ecological barrier

Sympatry

Two organisms, populations, or two distinct varieties of species or taxa, coexisting with one another in the same relative geographic area/habitat

How is phylogeography studied?

Uiparentally inherited genetic markers Mitochondrial or chloroplast DNA sequences, and as such they track the genealogical history of either the maternal or paternal line; in plants this is the pollen (male) or seed (female) parent.

What's happening to current biodiversity

World is witnessing a decline in biodiversity which may be greater in magnitude than even previous mass-extinction events

Because the earth's average surface temperature is so high, the Earth's surface radiates more energy as _________ radiation than it absorbs as incoming ________ radiation

long-wave; short-wave