2.6 Measuring the Distribution of Organisms

Question 1

What can quantitative data be used to do?

Answer 1

Describe how physical factors may be affecting the distribution of organisms in a particular habitat

Question 2

What are the two ways quantitative data can be obtained?

Answer 2

By random quantitative sampling using a quadrat, or by sampling along a transect

Question 3

What is a quadrat?

Answer 3

A square frame made of metal or wood (may be subdivided in to a grid)

Question 4

How is a quadrat used?

Answer 4

Several quadrats are placed randomly in a field (close your eyes and throw it or throw it behind you) then the investigator counts the amounts of organisms in each quadrat. This is used to estimate the number of organisms in the whole field

Question 5

How is a transect used?

Answer 5

A line is marked between two points. A quadrat is placed every five metres along the line and the organisms in each quadrat are counted