11.3 Sampling Techniques

Question 1

Pooter (Animals)

Answer 1

Used to catch small insects by sucking on a mouthpiece, insects are drawn in by a tube. A filter before the mouthpiece prevents them from being sucked in the mouth

Question 2

Sweep nets (Animals)

Answer 2

Used to catch insects in areas of long grass

Question 3

Pitfall traps (Animals)

Answer 3

Used to catch small, crawling invertebrates like spiders and bugs. A hole is dug in the ground which insects fall into. Needs to be deep enough so insects do not crawl out and protected by a roof so rainwater does not fill it

Question 4

Tree beating (Animals)

Answer 4

Used to take samples of invertebrate living in a tree. Put a large white cloth under the tree and then shake the tree to dislodge the invertebrates.

Question 5

Kick sampling (Animals)

Answer 5

Used to study the organisms living in a river. Kick the river bank and bed to disturb the organisms. Hold down a net to capture any organisms released into the water

Question 6

Quadrats (Plants)

Answer 6

Square frame divided into grid of equal sections. 3 main ways to sample population include density frequency and percentage cover

Question 7

How to measure density in a qudarat

Answer 7

If the number of plants can be seen clearly, count the number of them in a 1mx1m square quadrant. This gives the density per square meter

Question 8

How to calculate frequency in a quadrat

Answer 8

Use the small grids and count the number of squares a particular species is present in. if 8 in a 25 square quadrant the frequency would be 32%

Question 9

How to calculate percentage cover in a quadrat

Answer 9

Used when there is a lot of one specie or is difficult to count. You estimate by eye the area within a quadrat that a particular plant specie covers

Question 10

What technique is used to estimate animal population size

Answer 10

Capture mark release recapture

Question 11

How does capture mark release recapture work

Answer 11

• Capture as many individuals of a specie you can in an area
• Mark these organisms and then release them back into the community
• Give some time to let the organisms redistribute and then recapture all of the organisms
  -By comparing the number or marked organisms vs non marked organisms caught it can show how big a population in. Lots of non marked means bigger population

Question 12

Abiotic factors

Answer 12

Non living conditions in a habitat which have direct effects on the living organisms that live there.

Question 13

what is used to calculate wind speed

Answer 13

Anemometer (ms-1)

Question 14

what is used to calculate light intensity

Answer 14

light probe (lx)

Question 15

what is used to calculate relative humidity

Answer 15

humidity sensor (mg dm-3)

Question 16

what is used to calculate ph

Answer 16

ph probe (ph)

Question 17

what is used to calculate temperature

Answer 17

thermometer probe (c)