A non-living, physical factor that may influence an organism or ecosystem; for example, temperature, sunlight, pH, salinity, precipitation.
Biochemical Oxygen Demand (BOD)
A measure of the amount of dissolve oxygen required to break down the organic material in a given volume of water through aerobic biological activity.
Capable of being broken down by natural biological processes; for example, the activities of decompose organisms.
The amount of biological or living diversity per unit area. It includes the concepts of species diversity, habitat diversity and genetic diversity.
The mass of organic material in organisms or ecosystems, usually per unit area. Sometimes the term "dry weight biomass" is used where mass is measured after the removal of water. Water is not organic material and inorganic material is usually relatively insignificant in terms of mass.
A collection of ecosystems sharing similar climatic conditions; for example, tundra, tropical rainforest, desert.