Sampling Techniques

What is a quadrat?

• A small cut made in a dead organism

• A frame used to measure distribution

• A line across part of a habitat

• A device to measure moisture content

Why should a quadrat be placed randomly?

• To get a representative sample

• So we don't hurt slow moving animals

• So it's difficult to count the plants underneath

• To save time

A species must take up _____ of the quadrat to be counted.

Draw a quadrat

Why is it better to use a quadrat with lots of small squares?

• Because they are quicker

• So we don't crush any of the plants

• It's easier to decide if the box is 50% full

• To get a more accurate estimate of the distribution in the are

Why do we use transects and quadrats?

• To measure the distribution of a species over an area

• To measure the number of animals in a habitat

How is a quadrat placed randomly?

• By spinning around and throwing it

• By throwing it over your shoulder

• Using a random number generator

• By placing it down a transect

How many boxes have soil in?

• 10/25

• 19/25

• 23/25

• 12/25

What is the mean number of buttercups?

• 17

• 12.7

• 18

• 22

What is a mean number?

• The middle number

• Add all the values then divide by the number of values

• The number you see the most

• The difference between the largest and smallest number