Ecosystems & Biodiversity

Biodiversity is the variety of species and ecosystems on earth and the ecological processes of which they are a part. Can be further categorised as ecosystem diversity, species diversity and genetic diversity.

Ecosystem diversity: Is the variation in habitats, living communities and ecological processes in the living world.

The variety of genetic characteristics involved in the genetic makeup of a species.

Used to find out how common or rare a species is in a defined area. They are thrown randomly within the area to be investigated OR another form of randomised sampling is used e.g. systematic, stratified, simple.

Density is the number of individuals of the same species present per unit area or unit volume (e.g. m2). The average is calculated from the samples collected in a given area.

Frequency in sampling is the proportion/number of quadrats that each species occurs in.

Percentage cover is the measure of the amount of cover of a particular species in a quadrat.

A transect is a line across a community of organisms. It can be as simple as a string or rope placed in a line on the ground. The string is marked off in measured distance intervals, and the species at each point are marked and noted. Quadrats are usually placed at these intervals.

Transects are usually carried out to provide information on the distribution of a species in the community. The number or organisms of each species can be observed and recorded at specific regular intervals along a transect, using a quadrat.

A biotic index/biodiversity index is a scale showing the quality of an environment based on types of organisms which inhabit it.

Simpson’s biodiversity index, Trent biotic index and Lincoln index

Simpson’s Biodiversity Index is a measure of diversity which considers the number of species present, plus the relative abundance of each species.

The Lincoln Index is a method of estimating population sizes of individual animal species in a particular area using capture-mark-recapture.

Banding: a visible coded metal or plastic loop attached around part of the organism. Tagging: a visible coded metal or plastic tag inserted into or onto the organism. Painting: A code painted onto the surface of an organism. Surgical Implantation: A microchip inserted into the organism; read by an electronic reader. Hair clipping: A distinctive area of fur trimmed on a small mammal.

Biodiversity is the variety of species and ecosystems on earth and the ecological processes of which they are a part. Can be further categorised as ecosystem diversity, species diversity and genetic diversity.

Ecosystem diversity: Is the variation in habitats, living communities and ecological processes in the living world.

Is the variety of genetic characteristics involved in the genetic makeup of a species.

To find out how common or rare a species is in a defined area. They are thrown randomly within the area to be investigated OR another form of randomised sampling is used e.g. systematic, stratified, simple.

Density is the number of individuals of the same species present per unit area or unit volume (e.g. m2). The average is calculated from the samples collected in a given area.

Frequency in sampling is the proportion/number of quadrats that each species occurs in.

Percentage cover is the measure of the amount of cover of a particular species in a quadrat.

A transect is a line across a community of organisms. It can be as simple as a string or rope placed in a line on the ground. The string is marked off in measured distance intervals, and the species at each point are marked and noted. Quadrats are usually placed at these intervals.

This is particularly appropriate where environmental factors might change e.g. along an environmental gradient or where one ecosystem transitions to another. Transects are usually carried out to provide information on the distribution of a species in the community.

A biotic index/biodiversity index is a scale showing the quality of an environment based on types of organisms which inhabit it.