chapter 3

Community Ecology

Climate greatly affects the distribution of organisms in the biosphere, creating distinct biological communities.

Species adapt to changes in biotic and abiotic factors, which leads to greater biodiversity.

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• Species in the same community interact in many different ways.

• For example, competition can occur among organisms for the same resources in the community.

• Succession describes the gradual change in the type of plants in a community.

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• The distribution of living things is limited by the environmental conditions in different areas of Earth.

• The distribution of life in the biosphere depends on abiotic factors like average temperature and precipitation (the climate).

• Climate is affected by location on Earth.

• Where abiotic factors are similar, similar ecosystems exist with similar organisms.

• Biomes are major ecosystems with similar abiotic conditions containing similar organisms.

3.1

VOCABULARYclimate

latitude

elevation

climatograph

biome

tundra

permafrost

boreal forest

canopy

temperate deciduous

forest

understorey

temperate rainforests

grassland

savannas

tropical rainforests

deserts

polar ice

Factors affecting Abiotic Conditions

•Climate•Latitude & Elevation

See Fig 5 & 6 p. 52-53 In Textbook

Biomes ProjectsSee your Biomes Projects Handout for details. These are due June 8th!!!! You are responsible for teaching the class about your Biome. The class will have sharts to fill in while watching your presentations

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•Tropical Rainforest•Temperate Rainforest•Tundra•Deciduous Forest•Boreal Forest•Taiga•Savannah•Grassland•Desert

3.2

VOCABULARY

adaptation

natural selection

mimicry

coevolution

biodiversity

primary

productivity

extinction

extirpation

keystone species

• When faced with a change in the biotic or abiotic conditions in an ecosystem, a population will adapt to the changes, leave the area, or die out.• An adaptation is any genetic trait that

improves an organism’s chance of surviving and reproducing.

• Natural selection is a process that favours the survival of organisms with traits that make them better adapted to the environment, while eliminating organisms that are poorly adapted.

• Predation is a strong force in natural selection.

• The variety of organisms and the variation among them within a given ecosystem or biome is called biodiversity, which varies from one location to another as a function of abiotic factors.

3.3

VOCABULARY

niche

competition

interspecific

competition

intraspecific

competition

resource

partitioning

adaptive radiation

proliferation

foreign species

ecological

succession

pioneer species

primary succession

climax community

secondary

succession

• Competition can occur between different species in the community or between individuals of the same species.

• Foreign species may be introduced to ecosystems and out-compete native species.

• Succession is a process of gradual change in the types of plants that represent the structure of a community.

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Key Ideas

• The biosphere contains distinct biological communities.

• Species adapt to changes in environmental conditions and to other organisms.

• Species in communities interact in many different ways.

• Succession is an indication of change in an ecosystem.

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