How many daisies?

Post on 24-Feb-2016

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How many daisies?. How did you estimate the number of daisies? Did you try to count them all? Or did you use another method? See if this will help…. Using a grid like this helps you to estimate the number of plants in an area. But… - PowerPoint PPT Presentation

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How did you estimate the number of daisies?Did you try to count them all?Or did you use another method?

See if this will help…

Using a grid like this helps you to estimate the number of plants in an area.But…If you were asked to count the number of daisies in a field, this would be impractical.Instead we use quadrats.

Random sampling

Stratified Random Sampling

Systematic sampling

Now let’s go try it!

I luuuvvvs me some ecology!

STARTER:

Calculate the percentage density of Plant A in the following experiment:

Quadrat Site 1 Site 2

1 12 15

2 23 9

3 0 35

4 9 28

5 27 16

Quadrat used

0.5m

0.5m

25m 25m

30m25m

Site 1Site 2

Percentage Frequency

• Percentage of the total quadrat number that the species was present in.

Percentage Cover (%) ACFOR Scale Score

>50 Abundant 5

25-50 Common 4

12-25 Frequent 3

6-12 Occasional 2

<6, or single individual Rare 1

absent

Now let’s go practice calculating percentage cover!!

I luuuvvvs me some ecology!

Complete Q 11-13 in your booklet