Biology- Biodiversity (4.2)

Measure of variation found in living world, genes organisms contain and ecosystems in which they take part.
1 of 28
Genetic Biodiversity
Variation between individuals belonging to the same species eg. dog breeds.
2 of 28
Random Sampling
Randomly selected sample sites eg. number generator. + Non-biased. - May be unrepresentative (not covering all areas equally).
3 of 28
Opportunistic Sampling
Make decisions on where to sample based on prior knowledge/ during process. + Easier and quicker. - May be biased.
4 of 28
Stratified Sampling
Dividing a habitat into areas that appear different, and sample each area. +
5 of 28
Systematic Sampling
Samples taken at fixed intervals across habitat eg. transect. + Useful when habitat shows clear gradient in some environmental factor. - Other species not in line transect may be missed= underestimate of biodiversity.
6 of 28
Square frame, random number generator= coordinates. Calculate percentage cover as measure of abundance. Can divide into smaller squares or use point frame (needles). - Easy to bias readings by non-randomly placing quadrat. - Point frame can give 300%
7 of 28
Interupted Belt Transect and Continuous Belt Transect
IBT- take samples/ quadrat at set intervals. CBT- quadrat taken continuously- can study belt in detail.
8 of 28
Sweep Netting
Sweep stout net through vegetation to collect invertebrae, can empty onto white sheet to count.
9 of 28
Sucks invertebrae into jar before fly away.
10 of 28
Pitfall Trap
Container buried in soil so fall in.
11 of 28
Tullgreen Funnel
Collecting small animals from leaf litter. Move away from light at top and fall into beaker.
12 of 28
Longworth Trap
Humane trap, doesn't harm. Must be monitored to release. Use mark and recapture technique (C1 x C2) / C3.
13 of 28
Species Richness
Measure of how many different species are present. - Ignores no. individuals in each species.
14 of 28
Species Evenness
Measure of how evenly represented species are (abundance of individuals in each species).
15 of 28
Simpson's Index of Biodiversity
Takes into account species richness and evenness. 1- (n/N)2
16 of 28
What is the effect of a high value of Simpson's Index of Biodiversity?
A high value shows that the habitat is very diverse. This means that a small change (eg. disease/ predator) that may affect are species has little effect.
17 of 28
Genetic Diversity
More than one allele for a particular locus (position of gene on a chromosome). Can be estimated by calculating no. loci in one heterozygous individual. Can also be estimated by calculating percentage of loci in population have more than 1 allele.
18 of 28
Factors Affecting Biodiversity
Human population growth (destroy ecosystems for food and pollution). Agriculture (monoculture/ selective breeding and destroying habitats reduces genetic diversity). Climate change (less able to adapt so slowly migrate). Extinction rapidly increasing
19 of 28
Reasons to Maintain Biodiversity- Ecological
Interdependence- decline of species affects other species. Keystone species- one with disproportionate effect upon environment relative to its abundance. Genetic resource- potential medicines.
20 of 28
Reasons to Maintain Biodiversity- Economic
Food production- soil depletion (loss of soil fertility caused by removal of minerals by continuous cropping of monocultures).
21 of 28
Reasons to Maintain Biodiversity- Aesthetic
Joy/ wellbeing- patients recover faster. Flooding/ drought.
22 of 28
Conservation In Situ
Normal Habitat. Legislation (country prevents hunting...). International laws. Wildlife reserves. National Parks. National Nature Reserves. Sites of Specific Scientific Interest. Marine conservation zones.
23 of 28
Evaluation of Conservation In Situ
+ Natural environment. Permanently protects biodiversity and representativeness. Allows management so ecological integrity is maintained. Facilitates research. - Conditions for extinction may still be present. May be too late.
24 of 28
Conservation Ex Situ
Outside normal habitat. Zoos (breed and carry out research). + Protection from poaching/predation. Monitor health, medical assistance. - Disease exposure., Limited genetic diversity. Botanical Gardens/ Seed Banks. + Seeds easy to collect. - Asexual.
25 of 28
Convention of International Trade in Endangered Species ensures trade doesn't threaten survival of endangered species. - Hard to enforce.
26 of 28
Rio Convention on Biological Diversity
Promote sustainable development, with focus on people and sources of food, medicines, fresh air, water and shelter.
27 of 28
Countryside Stewardship Scheme
Aim to enhance natural beauty and diversity of countryside.
28 of 28

Other cards in this set

Card 2


Genetic Biodiversity


Variation between individuals belonging to the same species eg. dog breeds.

Card 3


Random Sampling


Preview of the front of card 3

Card 4


Opportunistic Sampling


Preview of the front of card 4

Card 5


Stratified Sampling


Preview of the front of card 5
View more cards


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Ecology, ecosystems and environmental biology resources »