Recall the use of Quadrats to estimate the population size of an organism in two different areas


- This is a photo of a Sand Dune Ecosystem which is made up of a number of populations which form the community. The habitat is shown below and is split in two different areas by a fence. One side which is grazed by cattle and one side which is ungrazed.

- So we have to different areas within an ecosystems and could choose to study the population on either side. We could do this by counting the number of individuals in the population. The technique is called 'Quadrating.' Based on squares hence the word "Quad". These squares can be made of any material (wood, string, metal) to form a square grid.

- The Quadrat is used to take a sample of the population in a selected area. This is done by laying down the Quadrat and counting the number of individuals inside the square. If this is done for every square in the area, it can be used to gain an estimate of the population size.

- To summarise Quadrats are a method of sampling different locations so populations can be compared.