how it is adapted to the environment

ex) physiological, evolutionary, behavioral ecology

How are resources being used and being put back into the environment

ex) energy flow, chemical cycling

Research on the distribution and abundance of species; how species interact with each other and the environment

Helps understand how problems first occured

Develop conservation and management plans to limit or repair damage to the ecosystem from human actions

The information that can help people solve the practical problems

• ecology provides scientific understanding of living things and their environment
• environmentalism is more about conservation and preservation of life on Earth

Rachel Carson

• wrote the Silent Spring in 1962

non living things that affect the environment

ex) climate, soil type, periodic disturbances, etc.

living things that affect the environment

ex) competitors, predators, pathogens, etc.

long term weather patterns

temperature, precipitation, sunlight, wind

• temp and water are the major influence

• the tilt of the earth on its axis
• spring and fall equinoxes
• extent of seasonal variation increases with latitude

• near the equator
• more direct sun
• no change in day length

• less direct sun
• large seasonal changes in day length

the region where we know life exists

extends several kilometers into the atmosphere and at least 3000 meters below earth's surface

A type of ecosystem that covers broad regions

• major terrestrial or aquatic life zones
• assemblages of various types of organism in specific climates
• characterized by vegetation types in terrestrial biomes
• characterized by the physical environment in aquatic biomes

largest part of the biosphere

• lakes
• streams and rivers
• wetlands
• estuaries
• intertidal zones
• pelagic zone
• coral reefs
• deep sea benthos

O2 goes down, nutrients come up

essential for survival and growth of aquatic organisms

nutrient poor, O2 rich

good

nutrient rich, O2 poor

bad, tends to be green

open blue water

extends to greater depths than coastal marine waters

seafloor below the surface waters of coastal and pelagic zones

no sunlight

continuously cold and high water pressure

• cover 22% of the earth's surface
• most important characteristic is vegetation
• 9 major groups

1. tropical forest
2. savanna
3. desert
4. chaparral
5. temperate deciduous forest
6. temperate grassland
7. coniferous forest
8. tundra
9. polar and mountain ice

• equatorial regions
• rain and dry forests
• warm year round with little variation
• vertically layered
• intense competion for light
• emergent trees, canopy, subcanopy, shrub and herb layer, epiphytes
• population growth
• agricultural development

• near 30 N and 30 S
• <30 cm rain a year
• temp is variable
• low, widely scattered vegetation
• cacti, deep rooted shrubs, herbs that grow during moist periods
• reduction of biodiversity

• equatorial regions
• seasonal rainfall (30-50 cm/year)
• dry season up to 9 months
• warm year round
• trees are thorny, small leaves, adapted to dry conditions
• fire adapted
• grasses and forbs
• earliest humans lived in savannas

• midlatitude coastal regions
• precipitation is highly seasonal, rainy winters, long dry summers
• average seasonal temps
• shrubs and small trees, grasses and herbs
• high plant diversity
• adaption to drought and fire
• heavily developed

• temperate zone
• South Africa, Hungary, Argentina, Uruguay, Russia, North America
• precipitation highly seasonal
• dry winters and wet summers
• grasses and forbs, large mammals
• prime agricultural land

• midlatitude in Northern Hemisphere
• precipitation, 70-200 cm/year
• cold winter, hot and humid summer
• vertical layers, understory trees, shrubs layer, herbaceous layer
• mainly deciduous trees

• Northern North America and Eurasia
• largest terrestrial biome on Earth
• precipitation 30-70 cm/year
• cold long winters
• cone bearing trees, cone shape plants
• old growth

• expansive areas of the Artic
• 20% of Earth's land surface
• precipitation averages 20-60 cm/year
• long cold winters and short cool summers
• mosses, grasses, forbs, dwarf shrubs, lichens
• climate change, mineral and oil extraction

the study of populations in relation to their environment

explores how biotic and abiotic factors influence population density, distribution, size, and age structure

• size(N)
• density
• dispersion
• genetic characteristics
• demography(change in N through time)

number of individuals per unit area or volume

determining the density of a population is extremely difficult

sampling methods:

1. random sampling of a subpopulation
2. mark recapture

not a static property

• additions-birth, immigration
• deletions-death, emigration

pattern of spacing among individuals within the boundaries of the population

1. clumped
2. uniform
3. random

individuals aggregate in patches

influenced by resource availability and behavior

ex) wolves

MOST COMMON

individuals are evenly spaces

influenced by social interactions such as territoriality

ex) penguins

the position of each individual is independent of other individuals

ex) flowers and plants

study of vital statistics of populations and how they change over time

population ecology focuses on processes

3 tools to measure:

1. life tables
2. survivorship curves
3. reproductive tables

ΔN/Δt= B+I-M-E

B=births

I=immigration

M=mortality

E=emigration

N=size

t=time

The heart of population ecology

an age specific summary of the survival pattern of a population

follow the fate of a cohort

the traits that affect an organism's schedule of reproduction and survival make up its life history

3 basic variables:

1. when reproduction begins
2. how often reproduced
3. how many offspring produced

adaptive, presumably derived from natural selection

characteristics that influence population growth:

• age to maturity

J-shaped curve

typical of populations introduced to new/unfilled environments

keeps growing past carrying capacity

(r)

birth rate-death rate

r>0 population growth

r<0 population decline

effects steepness of growth curve

maximum growth rate for a population

dN/dt=rmaxN

varies among species

influenced by:

• age of reproduction
• # of young per reproductive effort
• time between production of young
• survival of young

the "real world"

limit to number of individuals that can occupy a habitat

begins exponentially, but levels off around carrying capacity

s shaped curve

exponential growth

max reproductive success

often in disturbed habitats

below carrying capacity

"Big Bang"

pioneer species

ex) rabbits, oysters

near carrying capacity

longer life span

older growth

strong competition among individuals

less offspring

ex) humans, oak trees

now 6.8 billion

7.8 to 10.8 billion by 2050

began to slow in the 1960s

one way to calculate K

summarizes land/water area available to each nation to

-produce all resources is consumes

-absorb wastes generated

-food

malnutrition and famine is common

-space

few limits on how closely humans can be together

-nonrenewable resources

metals, water, capacity of earth to absorb wastes