Ecology

Ch2 Sec 3

Page 39-42

Ecology links Life Science & Earth Science

Ecology is the study of the complex relationships between living things and their nonliving, or abiotic, environment

Ecosystems A community of organisms and the

environment that the organisms inhabit is an ecosystem

From the Greek oikos—eco– Means house

Distribution of Ecoystems

Ecosystems haveABIOTIC COMPONENTS BIOTIC COMPONENTS

Sunlight Primary producers

Temperature Herbivores

Precipitation Carnivores

Water or moisture Omnivores

Soil or water chemistry (e.g., P, NH4+) Detritivores

etc. etc.

Elements Producers—produce their own

food– Plants

Consumers—get their energy from eating other organisms

Some consumers get their energy breaking down dead organisms—decomposers

Healthy systems have a balance of producers, consumers, and decomposers

Balancing Forces in Ecosystems

Organisms use matter and energy Because those amounts are limited so

is the number of organisms

The largest population that an environment can support at any given time is called the carrying capacity

Ecological Responses to Change Events such as forest fires can disrupt

ecosystems Often organisms move elsewhere if

other land is available and return when the area has recovered

Succession Primary—entrance of life to a formerly

lifeless area—after a lava flow, after a glacier

Secondary—reentry of life after a disaster

Climax community—when the ecosystem reaches a point of equilibrium

Primary Succession

Secondary Succession

Climax Community Occurs after many years when the

ecosystem reaches maturity and populations remain relatively constant.

Energy transfer The ultimate source of energy is the

sun Plants capture energy by a chemical

process known as photosynthesis This energy then flows through the

ecosystem through the plants

Energy pyramidEnergy is changed in

a series of chemical reactions

The amount of energy decreases in each transfer as some is lost

Food web A diagram that

shows the feeding relationship among organisms in an environment

Human Stewardship Changes in

ecosystems can affect the ability of an area to sustain a human population

Ecological balances can be affected by human activity

Check out these sites Food web info

http://www.vtaide.com/png/foodchains.htm

Extension Extensions are information as to

where to find extra material about an interesting subject.

If you find a topic you are very interested in, consider doing extra credit research over the topic.