Sampling

Question 1

Quadrat ? (4 key points!)

Answer 1

Used to count the number of plants of the ground
🌺🌸🌻
A frame split into smaller squares provides greater accuracy
🌺🌸🌻
Can be multiplied to give an estimate for a large area
🌺🌸🌻
Divisions / grid prevents mis-counting and makes it easier to convert to a percentage

Question 2

How to quadrats have increased accuracy?

Answer 2

A frame split into smaller squares proves a greater accuracy ….
(Less chance of mis-counting a species)

Question 3

Point frame quadrat??

Answer 3

Only count the plants that touch the points
🌸🌻🌺
Much quicker than quadrat with squares but less accurate!!

Question 4

Which is more accurate… Point frame quadrat or square quadrat??

Answer 4

Square quadrat

Question 5

What are coordinates used for?

Answer 5

Used to find where to place the quadrat when sampling an area
🌸🌻🌺
Good for a large open areas (field or a park!)

Question 6

How to set up and use coordinates??

Answer 6

Draw coordinates or a grid over a map of the area
✨✨✨
Randomly pick numbers and use coordinates to select where to place the quadrat

💁e.g. Pick numbers out of a hat

Question 7

Transacts ?

Answer 7

Used to find where to place the quadrat when sampling a cross section of an area
🌺🌸🌻
Good for straight lines (riverbanks or roadsides!)
🌻🌺🌸
Can be continuous or interrupted!

Question 8

Line transect??

Answer 8

Place the tape between 2 points, at intervals note what plant is touching the line!! ✨💕

Question 9

Belt transect???

Answer 9

Like a line transect but with a quadrat (either sort) alongside the line!! ☀️🍸😬

Question 10

Ways to sample animals??

Answer 10

Sweep net - flying insects
🐜🐝🐞

Fishing nets - aquatic animals
🐠🐟🐬

Pitfall traps - crawling animals
🐛🐢🐭

Beating tray - hedge / tree
🌲🌳🌴

Question 11

When should you not do Mark-Release capture?

Answer 11

During breeding season as young are being produced

Question 12

How to do mark-release capture??

Answer 12

Capture sample

Mark sample…
Appropriate method of marking that does not harm organisms (e.g. marking it more visible to predators)

Release

Take a second sample and count the marked organisms!!

Question 13

Population estimate from mark-release capture ??

Answer 13

(No. in sample 1. X no. in sample 2 )

Divided by… No. Marked in sample 2!!

Question 14

Continuous variation ?

Answer 14

Normally numbers...
✨✨✨
This type of characteristic can have decimal places (height)
✨✨✨
Normally shown as a line graph!!

Question 15

Discontinuous variation?

Answer 15

Normally catalogues (hair colour)
✨✨✨
This is normally a bar graph

Question 16

Random sampling….

Answer 16

Avoid bias!!!!

Question 17

Describe how you would decide the number of quadrats to use in order to collect REPRESENTATIVE data ??

Answer 17

1) calculate a running mean
2) when enough quadrats, this shows little change
3) enough to carry out a statistical test
4) a large number to make sure results are reliable
5) need to make sure work. Can be carried out in the time available
6) regards large numbers as 10% +

Question 18

How would you place your quadrats at random? (In a forest)

Answer 18

1) method of positioning quadrats (find coordinates on a grid)
2) method of generating random numbers (picking numbers from a hat at random)

Question 19

Explain the difference between accurate and reliable for an experiment ?

Answer 19

Accurate means without error (taking measurements)
✨✨✨
Reliable means that figures can be reproduced when measurements are repeated / show little variation from the true value….

Question 20

Use the words probability and chance to explain what is the meaning of ‘differed significantly (p

Answer 20

1) there was a probability of less than 0.05 / 5%

2) that the DIFFERENCE was due to chance