Chapter 4: Ecology

Ecology

Study of the interaction between living things and between organisms and their environment

Biosphere

Part of the planet containing living organisms

Ecosystem

A group of clearly distinguished organisms that interact with their environment as a unit

Habitat

The place where a plant or animal lives

Population

All the members of the same species living in an area

Community

All the different populations in an area

Abiotic factors

Non living factors

Biotic factors

Living factors

Climatic factors

Refers to weather over a long period of time

Eda factors

Producers

Organisms that carry out photosynthesis

Flora

All the plants in the ecosystem

Consumers

Organisms that take in food from another organism

Fauna

All the animals in an ecosystem

Decomposers

Organisms that feed off dead organic matter

Detritus feeders

Organisms that feed on small pieces of dead organic matter

Food chain

A sequence of organisms in which each one is eaten by the next member in the chain

Trophic level

A feeding stage in a food chain

Food web

Consists of two or more interlinked food chains

Pyramid of numbers

Represents the number of organism at each trophic level in a food chain

Niche of an organism

The functional role it plays in the community

Nutrient recycling

The way in which elements are exchanged between the living and non living components of an ecosystem

Nitrogen fixation

Conversion of nitrogen gas into ammonia, ammonium or nitrate

Nitrification

Conversion of ammonia and ammonium compounds to nitrite and then to nitrate

Denitrification

Conversion of nitrates into nitrogen gas

Pollution

Any harmful addition to the environment

Pollutant

Harmful additions to the environment

Conservation

Wise management of existing resources in ecosystems, in order to maintain habitats and species

Eutrophication

Addition of nutrients to fresh water

Environment

All the external factors that influence an organism