Distribution and Abundance of species is dictated by two factors

The vagaries of history

and

Interactions among organisms and their environments

1) W/ physical environment

2) Direct

3) Reciprocal interactions

4) Indirect (cascades, etc)

How interactions (among spp, & between spp and their environment) shape spp through selection and adapt.

and

Consequences of the resulting evolutionary processes to populations, communities, an ecosystems

Sea otter-> urchin -> kelp.

Kelp can develop phlorotannins. These can concentrate in a smaller trophic chain which makes it an evolutionary arms race. 

1) +/- interactions generally result in the evolution of defense and resistance (Red queen effect)

2) Geographic mosaic of coevolution

Fretwell theory: Even #: plants limited by herbivores

Odd#: Herbivores limited by predators

Ex) sea otter->urchin->kelp

1) Habitat

2) Production
3) Flow

1) Many more linkages among species than species themselves

2) Complexity increasingly dominated by indirect pathways as species number grows

1) Direct observation

2) Stomach contents

3) Other measures (fatty acids)

Herbivores eat plants, the world is green, and fossil fuels accumulate over the history of the earth from plants.

Therefore herbivores are not food limited and must be limited by something else. (predators)

How do you define community?

(4 ways)

1) By conspicuous species (corals, redwoods, kelps,..)

2) By Taxa (insects, mammals,...)

3) By Guilds (a group of spp using common resource)

4) By functional groups (subset that functions in similar ways- e.g. sucking insects; large mammal predators)

Trophic status and variation in interaction strength (Strength of the role of the spp on another spp)

Int strength always described in terms of 'consumer-prey' interactions.

Most int's are weak interactions, few are strong.

Numerical dominants, keystone spp, and ecosystem engineers.

Numerical dominants-> Redwood forest

Keystone spp-> high per capita int str

Ecosystem engineers-> exerts impact by changing the physical environment of the system

When spp. filters break down

and

There has to be a mass extinction in the recipient biota

When people break down spp. filters.

ex) ballast water dumping

Clements -> everything works together

Gleason -> everything independent.

Facilitation: early spp. facilitates the colonization of later spp.

Tolerance: no interaction between early and later spp.

Inhibition: Every spp. provides negative interactions to the next.

there are three patterns:

1) extinction, 2) evolution 3) movement

Latitudinal patterns are dramatic, spp. diversity gradients around latitude changes. There are three theories of why this is:

time theory: tropics are older

competition:

climatic stability: climate in tropics is stable

productivity: tropics are more productive

Through richness or evenness.

Richness is the enumeration of spp.

Evenness  is the relative abundance of individuals across spp.

the fact that many spp. are unknown, therefore comparisons of samples are unfair. 

plot of S v. N

How do you measure spp. diversity?

Explain the following variables:

S

Ni

N

Pi

Rarefaction curves measure spp. richness

Shannon Wiener index measures evenness

S=CA^z measures spp are relationships

Rarefaction technique: interpolate spp. diversity along rarefaction curve

Asymtotic technique: extrapolate diversity along rarefaction curve, with respect to the asymptote.

This equation shows the spp. diversity with respect to = the relationship of space and area. 

S= # of spp.

C= a constant

A= area

Z= rate of increasing diversity as area increases.  

Define the following variables wrt island biogeography:

P, S, λs, μs, ds/dt, I, E,Pi

P= # of spp. on the mainland

S= # of spp. on island

λs= Immigration

μs= Extinction

ds/dt= λs-μs

I= maximum immigration rate

E= maximum extinction rate

1) intermediate disturbance

2) Keystone predation

3) Niche Packing

4) Neutral

Highest spp. diversity in moderate disturbance density.

(middle of prabola of spp. diversity and disturbance density)

CAT CRAP GEL

Constancy

Amplitude

Trajectory stability

Cyclical stability

Resilience

Alternate stable states

Persistance

Global stability

Elasticity

Local Stability

Explain resiliance

If transition vector field is linear (if there is only one place for the forces to push) it is globally stable

If the transition vector field is non linear, (if it has multiplicity of stable states and there exists a "break point" where if it's pushed over, the the system will find a different stable position

Graphically if they function which describes this is continuous (passes the vertical line test) than it is a globally stable system.

If the function which describes this isn't continuous, than the system has multiple stable states.

1) It's the ultimate source of all energy

2)Variation in NPP can be an indication of ecosystem health

3) NPP is associated with the global carbon cycle.

4) Correlates pretty well with biomass

5) Correlates well w/ leaf area index

Terrestrial

Plant harvest before and after growing season (doesnt  take into account herb/detrit losses)

CO2 uptake or variation in CO2 concentration use C14

Remote sensing (NDVI) Measure greenness by sattelite

Aquatic

Photosynth & respiration in H20 samples/radio isotopes

Remote sensing- reflected light of green

never temperature

Water inhibits NPP

estimated to be 105 petagrams of C per year

54% of C taken up by terrestrail plants, 46% by oceans

Avg rate of NPP/year = 426g/cm^2/yr

Hydrothermal vents are fissures in the planets surface from which geothermically heated water issuse.

These occur where tectonic plates are moving apart.

2nd important pathway of production fixation of carbon by a chemically activated pathway.

Sulfur+CO2+O2+H20-> Sulphate & Carbohydrates

1) NPP

2) Trophic Status

3) Transfer efficiency

Terrestrial: Pyramid,

Aquatic: Inverted Pyramid

This is because the life cycles of trophic levels are inverse to generation times.

Comprised of 3 major components:

Consumption efficiency, assimilation efficiency, production efficiency : larger bodied > smaller bodied

Energy @ TL(x+1)/ Energy @ TL(x)

Endotherms < Ectotherms

Large bodied< small bodied
Herbivores < Carnivores

Phsyical transport

 and

Biological transport

isotopic ratio in sample of interest compared to some broadly accepted standard.

Standard of "N": atmosheric N

Standard of "C" : ?

The history of ecology through time.

World is fundamentally a product of the past

data on distribution and abundance are more limited

and

Can't perturb the past to study the response

Modern human records: hunting/trapping records, papers

Geological records: fossils, ice cores, sediment profiles, etc

Materials left by aboriginal peoples: middens, etc