4.2- Biodiveristy

Question 1

What does biodiversity mean?

Answer 1

Biodiversity is a measurement of all the different plant, animal, fungus and other microorganism species world wide, the genes they contain and the ecosystem of which form a part
-Biodiversity is about the structural and functional variety in the living world.

Question 2

What is habitat diversity?

Answer 2

A habitat is the place where individuals in a species live. The range of habitats in which different species live in is known as the habitat biodiversity. Common habitats found in the UK include sand dunes, woodland, meadows and streams. Each habitat will be occupied by a range of organisms

Question 3

What is species diversity?

Answer 3

A species consist of individual organisms that are very similar in appearance, anatomy, physiology, biochemistry and genetics. As a result, individuals in a species can interbreed freely to produce fertile offspring. The range of organisms found in a habitat contribute to the species biodiversity.

Question 4

What is also included in species biodiversity?

Answer 4

Species biodiversity is not a simple matter of counting different species. Two habitats may have an equal number of different species but they may not be considered equally diverse. For example, a wild meadow might have 25 species of grass and herbs. In any small sample you might find most of these species. Compare that with a garden lawn or a managed cow pasture. Here there may be 5 plant species, but one or two grass species dominate, with just a few individuals of the other species dotted about. The wild meadow is much more diverse because the 25 species are more evenly represented. We call the number of plant species the species richness. The degree to which the species are represented is known as the species evenness.

Question 5

What is genetic biodiversity?

Answer 5

Genetic biodiversity is the variation between individuals belonging to the same species. This is the variation found within any species that ensure s we do not all look identical. Genetic variation can create breeds within a species as shown by the difference between breeds of cattle or dogs.

Question 6

What can be used to measure biodiversity?

Answer 6

In order to measure biodiversity of a habitat, you need to observe all the species present, identify them all and count how many individuals of each species there are. This is not practical as it would be impossible to count all the species. You can sample a habitat. This means you select a small portion and study that carefully. Then you can multiply up the number of individuals of each species found, in order to estimate the number in the whole habitat. It is important that the samples taken are representatives of the habitat.

Question 7

How is random sampling carried out?

Answer 7

Sample sites inside the habitat are randomly selected. You can do this by deciding where to take samples before you study any are in detail. This can be achieved by using randomly generated numbers as coordinates for your samples.

Question 8

What are advantages of random sampling?

Answer 8

Ensures that the data are not biased by selective

Question 9

What are the disadvantages?

Answer 9

May not cover all areas of a habitat equally. Species with a low presence may be missed, leading to an underestimate of biodiversity.

Question 10

Name the non-random Techniques:

Answer 10

Opportunistic, stratified and systematic.

Question 11

How is Opportunistic sampling carried out?

Answer 11

This is when the researcher makes sampling decisions based on prior knowledge or during the process of collecting data. The research may deliberately sample an area that they know contains a particular species.

Question 12

What are the advantages of Opportunistic sampling?

Answer 12

Easier and quicker than random sampling

Question 13

What are the disadvantages of Opportunistic sampling?

Answer 13

• Data may be biased. The presence of large or colourful species may entice the researcher to include that species. This may lead to an overestimate of its importance and therefore an over estimate of biodiversity.

Question 14

How is stratified sampling carried out?

Answer 14

• Dividing a habitat into areas which appear different and sampling each area separately. For example patches of bracken in heathland might be sampled separately form the heather or gorse patches.

Question 15

What are the advantages of stratified sampling?

Answer 15

• Ensures that all different areas of a habitat are samples and species are not underrepresented due to the possibility that random sampling misses certain areas

Question 16

What are the disadvantages of stratified sampling?

Answer 16

• May lead to over representation of some areas in the sample, e.g. a disproportionate number of samples are taken in small areas that look different

Question 17

How is systematic sampling carried out?

Answer 17

This is when samples are taken art fixed intervals across the habitat. Line transects and belt transects are systematic techniques.

Question 18

What are the advantages of systematic sampling?

Answer 18

Useful when the habitats show a clear gradient in some environmental factor such as getting drier further from a pond.

Question 19

What are disadvantages of systematic sampling?

Answer 19

Only the species in the line or within the belt can be recorded, Other species may be missed leading to an underestimate of biodiversity.