1. Individual

2. Population

3. Community

4. Ecosystem

* looking @ one organism

* generalize to include entire species

* how do the get what they need?

* where do they get what they need?

* groups of individuals of the same species

*where are the?

*how many are there - past, present, future?

*reproduction rate, age structure

*interrelated populations

*ex: plants & animals combined = community

* which species are there? which species are together?

* ex: ponderosa pine and douglas firs

* how do they interact

*ex: ponderosa creates shade for doug firs

* community and abiotic factors (energy, nutrients, etc)

* flows and cycles of abiotic factors

* plant and environment interactions

* individual develpmental change that enhances physiological function

* ability to acclimate = an adaptation

* curve which shows how well a plant does with varying temp, water etc

* varies between species and indiv

* can function under adverse conditions (w/in plant)

ex: needle-leaf evergreens tolerate cold weather -> not a lot of surface area on needles, tough, don't freeze

* action to prevent adverse conditions

ex: deciduous trees drop leaves to avoid damaged leaf tissue in cold weather

* prevent dehydration

* closing stomata

* biomass allocation (keep below ground, rooty)

* rapid life cycle

* dormancy (trees and shrubs)

* face toward or away from the sun

* change in reflectance (albedo)

* heat generation (skunk cabbage)

* where individuals within the population are located

*depends on habitat availabilty

* resource concentration

* proximity to parents

* # of individuals that die at a given age

* survivorship curve = a graph of mortality

* type I - most survive

*type II

* type III - live fast, die young

* how many of each age in the population?

* can infer history of mortality and natality

*easy for trees vea dendrochronology

* births > deaths

* some fraction of population = born in given time period

* as pop increases so do # of births

* starts slowly and increases rapidly to infinity

* r=(births/carrying capacity) - (deaths/carrying capacity)

*P =Poe^(r*t)

*Po = starting pop, t = time, r=above rate, e = 2.71828

* starts out like geometric growth

* slows as it approaches a limit

* limit = carrying capacity = maximum stable population for a given environment (K)

*either birth rate goes down or death rate goes up until they are equal

*density dependent birth/death rate

* exponential growth until a key resource is depleted (like food) then die off

*can lead to extinction of the population

*deer example

*initial rapid growth

*population goes above K but density-dependet factors bring it back down (like logistic growth)

* delay between population increase and effet of limiting factors -> oscillation

* approaches K

* sustained oscillation

* delay between population increase and density-dependent factors influence

ex: predator and prey relationships

* sunlight heat water (climate)

* nutrients (soils)

* competition - limits resources

* stress - lower birth rates, raises death rates

*predation - increases with density

* parasites - lower BR, raise DR

how much energy, nutrients etc used to produce and raise offspring

includes nutrients provided to young/time to care for young etc

* type III (high mortality) reproduces early and often

* type I (low mortality) reproduces later and less often

* repeated disturbance keeps pop low (below k)

* early reproductive maturity

* high reproductive investment

*type III

* stable climate allows pop to grow to k

* r reduced as density increases

late reproductive maturity

* low reproductive investment

* high competition

*type I

* "holistic" "closed communities"

* strong species associations and interactions

* composition changes abruptly

*relationships between species determine composition

* "open communities"
* community composition changes gradually as environment changes (soils, moisture, temp etc)

* the environment determines composition

* too low = good for competitors

* too high = good for colonizers

* medium = both do ok

*medium resource availability = highest diversity

* too low = few species can tolerate

* high = favors competitors

* floods/tidal waves

* lava/ volcanic ash

* avalance

*rockslide

*glaciers

*winds, tornadoes, hurricanes

*fire

*drought

*disease

*humans

following a disturbance

parts of previous community are still there (100s of years)

following a minor disturbance

(10s of years)

N2 in atmosphere -> nitrates and ammonium in soil ->water and plants ->animals -> detritus ->n2 in atmosphere

water-> lakes and algae -> eutraphication = overgrowth of algae due to excess nitrogen runoff

n2 in atmosphere -> chemical fertilizers -> soil -> water and plants -> excess runs off into lakes

CO2 in Atmosphere -> plants -> animals -> detritus -> CO2 in Atmosphere and Fossil fuels

combustion of fossil fuels -> CO2 in atmosphere

the accumulation of energy in plant biomass

GPP - Respiration

climatic constraints

soil type

soil texture

specific plant specis

NPP ->growth incriment -> detritus and detrivores -> other detrivores and detritus

npp -> herbivores -> detritus and carnivors -> other carnivores, detritus, and detrivores -> other detrivores and detritus

warm, wet, tropical rain forest

tropical seasonal forests

scrub

warm/hot, dry

more scrub

desert

tropical savanna

midlatitude broadleaf/mixed forest

temperate rainforest

mediterranean shrubland

Climate = continental, dramatic seasonal change in daylenth, cP airmasses and midlatitude cyclones, p=pet, low temps, short growing season, Dfb, Dwb, Dwc, Dfd, Dwd

Soils = thin, acidic, few nutrients

Compositon = spruce-fir dominant canopy, some paper birch, aspen, esp after fire, grades into tundra

Disturbance = moderate fire frequency

Ecosystem = Npp @ 800g/m^2/year

Climate =  high altitude, cold temps, short growing season, orographic precip and cyclonic storms, "highland climates"

Soils = thin

Composition = varies w/ elevation -> different zones varying temp and moisture

Disturbance = *Fire*

Histonic Fire regime by zone, lower montane: high frequency low severity, upper montane: variable frequency/variable severity, subalpine: low frequency, high severity

Avalanches

Disease (beetles and budworms)

Logging