4.2: Biodiversity

Question 1

What is biodiversity

Answer 1

A measure of how varied an ecosystem is.
It can be measured in terms of genes, species or habitats

Question 2

What is habitat biodiversity?

Answer 2

A measure of how many different habitats are present in an area

Question 3

What is species diversity?

Answer 3

A measure of how many different species are present in an area, and how many different individuals of these species are there

Question 4

What is genetic diversity?

Answer 4

A measure of how many variations there are in the genetic code between individuals of a particular species or between different species

Question 5

What is species?

Answer 5

A group of organisms that sharrer common morphological, physiological and behavioural characteristics. Can interbreed. Produce fertile offspring

Question 6

What is species richness?

Answer 6

A measure of how many different species are present

Question 7

What is species eveness?

Answer 7

A measure of how the different populations compare within a particular ecosystem

Question 8

What is a gene?

Answer 8

A distinct sequence of nucleotides forming part of a chromosome, the order of which determine the order of monomers in a polypeptide chain or nucleic acid molecule which a cell may synthesise.

Question 9

What is a polymorphic gene?

Answer 9

Said to be polymorphic if more than one allele occupies that gene’ locus in a population

Question 10

What is gene locus?

Answer 10

Specific physical location of a gene or other DNA sequence on a chromosome, like a genetic street addrress

Question 11

How is genetic biodiversity measured?

Answer 11

Polymorphism:
proportion of polymorphic gene loci = number of polymorphic gene loci/total number of loci
The greater rumber of polymorphic gene loci, the greater the genetic biodiversity

Question 12

Why do we use sampling?

Answer 12

We use it when measuring the biodiversity of a habitat. This is to get a representative estimate of the population

Question 13

How do you ensure that your sample is representative?

Answer 13

• Take a large sample - you can calculate a mean statistical test to see if there are any differences or correlations you see are significant
• Randomly - to avoid bias

Question 14

How do we carry out random sampling?

Answer 14

1. Lay out two tape measures at right angles to each other to create a gridded area
2. Use a random sample generator to generate two numbers to serve coordinates on the grid
3. Place your quadrat at the coordinates and record the data

Question 15

What are types of non random sampling?

Answer 15

Opportunistic
Stratified
Systematic

Question 16

What is the opportunistic sampling method?

Answer 16

Unlikey to result in a sample that accurately represents the population
* Involves sampling organisms which are convinently available and therefore involves bias

Question 17

What is the stratified sampling method?

Answer 17

• Some populations or habitats can be seperated into groups to sample from or strata
• You would then take random smpales within each group (strata)

Question 18

What is the systematic sampling method?

Answer 18

Involves identifying different areas within a habitat to sample
It is used when there is a change in the districution of species within the habitat and you want to investigate the impact of this change on biodiversity.
Often involves a belt transect
- This is when you would place a single tape measure along the sample area and at regular set distances along the tape measure you would place your quadrat and record the data

Question 19

What are quadrats?

Answer 19

Used to sample plants and slow moving organisms
* A point frame is a horizontal bar with holes along it at set intervals that long pins are placed through
* The pin is pushed through to touch the ground and any species touching the pin is recorded

Question 20

What are the three types of methods used to record species present with a quadrat?

Answer 20

1. Density
2. Frequency
3. Percentage cover

Question 21

Density (method used to record when using a quadrat)

Answer 21

This is when you count the individuals

Question 22

Frequency (method used to record when using a quadrat)

Answer 22

This is a very quick methid and requires a gridded fram with 1000 squares
* You would count how many squares out of the 100, the species you are investigating are present
* If the plant species was present in 25 squares your frequecny would be 25%

Question 23

Percentage cover (method used to record when using a quadrat)

Answer 23

Estimate the percentage of the entire quadrat with the species being investigated
The method is quick but subjective and therefore results in lower accuracy
The method can be improved by standardising how the % is estimated

• E.g Using a quadrat with 100 squares + counting 1% for every small square that is at least half covered with the plant

Question 24

What are the sampling techniques for animals?

Answer 24

• Sweeping nets
• Pitfall traps
• Pooters
• Tullgren funnel
• Kick sampling

Question 25

What are sweeping nets used for?

Answer 25

These are nets that can be used to capture insects with long grass

Question 26

How/what are pitfall traps used for?

Answer 26

* A hole is dug in the ground and a pot is placed within it * Small invertabrates may crawl into the trap & will be unable to crawl out * A roof like structure is placed on top to prevent the trap from filling with rainwater * Investigaters will return daily to collect results and release animals

Question 27

# [](http://) How/What are pooters used for?

Answer 27

These are used to capture very small insects. * Two tubes are connected to a closed pot * The investigator sucks on one tube and places the other tube over the insect * This created suction and draws the insect into the pot

Question 28

How/What is tullgren funnel used for?

Answer 28

This is used to extract small organisms from within soil samples * The soil sample is dried using a heat lamp * This causes the animals to move in the opposite direction, downwards, where a collecting dish is placed

Question 29

How/What is kick sampling used for?

Answer 29

This is used to sample organisms within river beds. * One investigator will gently kick to the river bed to disturb the earth and the organisms within it * A second investigator stands behind them with a net to capture any organisms that are released

Question 30

How do you measure: * Species richness * Species eveness

Answer 30

Sampling methods can be used and you would record the number of different species present (species richness) To measure species eveness, for each species identified, you would also have to record the nimber of individuals present

Question 31

What are the factors affecting biodiversity?

Answer 31

* Human population * Agriculture * Climate change

Question 32

How does human population affect biodiversity?

Answer 32

* Population increasing at an exponential rate * Increased need for space for housing, farming and industry (requiring deforestation)

Question 33

How does agriculture affect biodiversity?

Answer 33

* Increasing agriculture to feed everyone * Clearing land for agriculture results in the destruction of habitats * Chemical pesticides or fertilisers may be added to the land and monocultures may be grown * All of this reduces the number of habitats and range of food sources

Question 34

How does climate change affect biodiversity?

Answer 34

* The increase in global temperature is melting polar ice caps and therefore destroying habitats * It is also resulting in sea levels rising which reduces biodiversity due to flooding * The higher global temperature and lower rainfall mean some plants and animals are unable to survive * Xerophytes are becoming the dominant species in some areas with these plants outcompeteing others as they can survive harsher abiotic conditions

Question 35

What are the three reasons for maintaining biodiversity?

Answer 35

* Ecological * Economic * Aesthetic

Question 36

What is the reasons for maintaining biodiversity? * Ecological * Economic * Aesthetic

Answer 36

Ecological: Biodiversity increases the stability of ecosystems Economic: A range of organisms contribute to medicine, ecotourism, science and technology Aesthetic: Humans take pleasure in the visual effects of biodiversity

Question 37

What is conservation?

Answer 37

Active management of ecosystem by humans once destroyed/concern arises

Question 38

What is preservation?

Answer 38

Management of ecosystem without the involvement of humans to prevent it from being destroyed by humans

Question 39

What are conservations in situ?

Answer 39

Conservation happens within habitat Advantages: * Genetic diversity is maintained as individuals are not bred captively * Putting measures in place to prevent the extinction of one species will have a positive impact on others all others species that depend on it as all organisms are interdependent Examples: * Marine conservation zones are ares designated for wildlife to recover and repopulate - areas where fishing and tourism arent allowed * Wildlife parks - same but on land

Question 40

What is conservation ex situ?

Answer 40

Involves removing organisms from their natural habitat to try and protect them, and its usually used in addition to in situ measures Examples: Botanical parks, seed banks, captive breeding

Question 41

Why are botanical parks helpful?

Answer 41

A wide range of plant species can be grown in botanical gardens, providing them with optimal conditions for growth

Question 42

Why are seed banks helpful?

Answer 42

They are like a store of genetic material. Seeds of a variety of plant species are stored in water and temperature controlled environments to keep them viable for longer They are stored as a backup for potential plant species that may go extinct

Question 42

Why is captive breeding helpful?

Answer 42

Involves reproducing animals in zoos or aquariums The aims is to increase the number of endangered species, and these individuals can then be reintroduced into the wild

Question 43

What is CITES?

Answer 43

The convention on international trade in endangered species of wild flora and fauna * Parties of the convention meet to update and set targets * Ensure that international trade on specimens of wild animals and plants does not threaten the survival of the species * International * 1975

Question 43

What is RCBD?

Answer 43

Rio convention on biological diversity * Conservation of biological diversity * Sustainable use of its components * The agreement covers all ecosystems, species and genetic resources * International * 1992

Question 43

What is CSS?

Answer 43

The countryside stewardship scheme (now environemental stewardship scheme) * England * 1991 * 3 aims - beauty, restoration of habitat and public access

Question 44

What is simple index of diversity? D = 1- [Σ(n/N)^2]

Answer 44

n = total number of organisms of a particular species N = the total number of organisms of all species