Biodiversity And Sampling

Question 1

What is biodiversity

Answer 1

The variety of living organisms that are found in a region

Question 2

Why is it important that humans don’t affect biodiversity

Answer 2

All the living organisms in a habitat depend on each other, so it’s important that human activity doesn’t have a negative effect on biodiversity.

Question 3

What are the 3 levels that biodiversity can be assessed at

Answer 3

Habitat/ecosystem biodiversity, species biodiversity and genetic biodiversity

Question 4

What does habitat biodiversity refer to

Answer 4

All the different habitats that are found in an area

Question 5

What will each habitat do

Answer 5

it will support a range of different species of animals, fungi and microorganisms

Question 6

What will an area with a rich habitat biodiversity have

Answer 6

A wide range of species

Question 7

What is species biodiversity

Answer 7

It tells us the species living in a certain area and it consists of 2 parts:

Question 8

What do scientists do to work out species biodiversity

Answer 8

By carrying out sampling

Question 9

What are the two different types of sampling

Answer 9

Random or non-random sampling

Question 10

What are the areas in random sampling selected by

Answer 10

Using random numbers which determine the coordinates on a map

Question 11

What does random sampling do

Answer 11

Because the area isn’t chosen by humans it reduces the chance of sampling bias.

Question 12

What might humans do if they choose the sampling site

Answer 12

They might choose the area that is easiest to reach or with a large number of organisms. However, these areas may not represent the whole area reducing reliability.

Question 13

What is opportunistic sampling an example of and what is it and what is a negative of it

Answer 13

It is an example of non-random sampling
Where the scientists select the organisms that are readily available. However these organisms may not be representative of all the organisms making it unreliable.

Question 15

What is stratified sampling an example of and what is it and what is a feature of it

Answer 15

The population is divided into subgroups or strata.

However the number of each group sampled has to be representative of the whole population.

Question 16

What is systematic sampling

Answer 16

Is used when there is a gradual change in the habitat from one place to another.

And is used to determine how the abundance of organisms changes as the habitat changes. Or how the features of the organisms change.

Question 17

What are the two ways to do systematic sampling

Answer 17

By using a belt transect or line transect

Question 18

How can a line transect be used for systematic sampling and what is a negative

Answer 18

A measuring tape is placed across the habitat and any organism touching the tape is sampled.

However these organisms may number of organisms touching the tape may be very small

Question 19

What is a belt transect and how is it used for systematic sampling

Answer 19

We place two parallel tapes across the habitat.
Any organisms found between the two tapes are sampled (e.g by using a quadrant)

Question 20

When we sample organisms at regular intervals along the transect what is it called

Answer 20

An interrupted belt transect.

Question 21

What can we do by sampling

Answer 21

We can estimate the abundance of an organism in a given area
We can also estimate features of an organism for example the mass.

Question 22

What is a problem with sampling

Answer 22

Is the issue of chance
Where if we select an organism there is a chance that, the organism may not be typical of the whole group.

Question 23

How is the problem with sampling reduced

Answer 23

By sampling a very large number of organisms

Meaning the measurements we take are more representative of the entire population —> increasing reliability

Question 24

What do we determine when sampling

Answer 24

Species evenness and richness

Question 25

How can insects be sampled with a sweeping net

Answer 25

The net is swept over plants several times which traps any insects present.

Question 26

How can we use a poster to catch small insects

Answer 26

A poster consists of two tubes The trapping tube which is placed near the insect we want to catch and we place the mouthpiece tube in our mouth and gently inhale The insect is now sucked into the trapping tube and into the container The mouthpiece tube has a piece of cloth to prevent the insect being sucked into the mouth.

Question 27

What are pitfall traps and what do they do

Answer 27

It is a container sunk into the ground and over the trap we place a cover which prevents rainwater from entering. Ground level animals fall into the trap which is deep enough to prevent them crawling out.

Question 28

What can we use to sample tiny organisms in soil

Answer 28

A Tullgren funnel

Question 29

What does a Tullgren funnel look like

Answer 29

DRAW IT

Question 30

What happen in a Tullgren funnel

Answer 30

A light bulb heats the surface of the soil causing the animals in the soil to move downwards away from the heat. Once they reach the bottom of the funnel they then fall into the container.

Question 31

What is kick sampling used for

Answer 31

It is used to sample for bottom-dwelling animals in the river bed

Question 32

How is kick sampling done

Answer 32

A net is placed downstream and the scientist gently kicks the river bed to dislodge any rocks or pebbles Any organisms which are disturbed move downstream and are caught in the net

Question 33

What is a frame quadrant used to sample

Answer 33

Slow moving or static animals

Question 34

How is a frame quadrant used to sample slow moving static animals

Answer 34

It is placed on the ground and any animals within the quadrant are sampled

Question 35

What can quadrat sampling also be used to sample and how is it interpreted

Answer 35

Be used to sample the plants in a habitat Where the value of the number of the species as a mean/ m2 is the density per m2

Question 36

How can we also use quadrants when plants have a very large amount in an area or are difficult to count

Answer 36

We look at how many squares in the quadrat contain the plant and this is reported as a percentage frequency

Question 37

What happens if a plant occupies a large amount of the quadrat

Answer 37

We can use percentage cover which is when we estimate by eye the percentage of the total area that is occupied by the plant

Question 38

What is a negative of percentage cover

Answer 38

It is not very accurate however it is very quick

Question 39

How can we increase the reliability of sampling by quadrants

Answer 39

By placing the quadrat at multiple positions and then calculating a mean

Question 40

What can be used instead of a bar quadrat

Answer 40

A point quadrat which is a wooden bar with holes in it, we position the bar over the ground and place metal pins into each hole. We count any plant that is touched by the pin.