Quadrat: is a tool used in ecology for sampling purposes, so that populations of species can be compared. Eg, a quadrat is placed on ground at random to count the vegetation within the sample taken.
Recap: All ecosystems are made up of a population which form a community + the habitat.
Calculating the pop size of an organisms using "quadrates" - It is important in the design method to add all the individual organisms in the habitat & to separate the land into two different areas. Often labeled "A" & "B." Eg: In a sand dune. Area marked A would be in the grazed area, & area marked B in ungrazed.