4.3 Quadrate Samples

describe the use of quadrates as a technique for sampling the distribution of organisms in their habitats.

Quadrate samples are always random to avoid bias and representative (large samples that are closest to the actual population as possible). samples are taken by setting up a grid system on the field. number the grid like a graph. generate random numbers and place quadrates accordingly to those coordinates. bigger samples are better but 10% of the actual area is best. after that, tabulate the data to form 2 columns (quadrate number and number of organisms/metres squared). add up the numbers and divide by the number of quadrates to get the number of organisms.