A pooter is used to collect small insects.

It works by sucking air containing the insects into a plastic container via a tube.

1. Record whether the species is present in each quadrat
2. Divide the number of times the species is found by the total number of samples
3. Multiply this value by 100

For example, if you placed a quadrat 10 times and found dandelion plants in 6 samples, then the species frequency for dandelions is: $\frac{6}{10}$x 100 = 60%  

We can minimise the effect of chance in random sampling by using a large sample size and analysing the data collected.

The best way to prevent sampling bias is to eliminate any human involvement in choosing the samples by carrying out random sampling. This involves taking measurements of individuals selected randomly from the population of organisms that is being investigated.

Random sampling is important to ensure the samples are representative of the whole area.

High genetic biodiversity allows for better adaptation to a changing environment and resistance to disease.

1. Species diversity - the number of different species and the number of individuals of each species
2. Genetic diversity - the variation in alleles within a population of a species
3. Habitat diversity - the number of different habitats

Density is measured by counting the number of individuals in a 1 m² quadrat.

Percentage cover is an estimate by eye of the area within a quadrat that a particular plant species covers.

A community is the living organisms of all species found in a particular ecosystem at a particular time

A habitat is the place where a species lives within an ecosystem

A niche is the role of an organism in an ecosystem, including its interactions and its method of obtaining energy

An ecosystem is a relatively self-contained, interacting community of organisms and their environment