4.2.1 Biodiversity

Question 1

biodiversity definition

Answer 1

range of habitats, number of different species, and their relative abundance, and the genetic diversity within a species within an area

Question 2

habitat definition

Answer 2

where an organism lives

Question 3

species definition

Answer 3

a group of organisms similar in appearance, physiology, and genetic whose members are able to interbreed to produce fertile offspring

Question 4

habitat diversity definition

Answer 4

range of habitats in which different species live within an area

Question 5

examples of habitats

Answer 5

sand dune
woodland
meadow
stream

Question 6

species biodiversity definition

Answer 6

number of different species living in a habitat (species richness) and their relative abundance (species evenness)

Question 7

genetic biodiversity definition

Answer 7

variation between individuals of the same species

Question 8

why sampling is necessary to measure biodiversity in an area

Answer 8

too time-consuming to count entire population
allows estimation for entire habitat
needs to be representative of entire habitat so sample range of species in habitat

Question 9

random sampling method

Answer 9

divide area into map/grid
use random number generator to create coordinates and sample area
take enough samples so data representative of habitat

Question 10

types of non-random sampling

Answer 10

stratified
systematic
opportunistic

Question 11

opportunistic sampling features

Answer 11

prior knowledge of site determines sample site

may deliberately sample area where you know organism is present

Question 12

opportunistic advantages

Answer 12

quicker than random sampling

Question 13

opportunistic disadvantages

Answer 13

may introduce bias

if sampling area known to have organism, overestimates its abundance/biodiversity generally

Question 14

stratified sampling features

Answer 14

specifically sampling areas in a habitat that seem very different

Question 15

stratified adv + disadv

Answer 15

no under representation of any areas (all different areas sampled)
areas overestimated if too many samples taken in proportionally smaller areas

Question 16

systematic sampling features

Answer 16

samples taken at regular, predetermined intervals across habitat
uses belt/line transect

Question 17

systematic advantages

Answer 17

line transfer shows how gradual change in an environment factor affects different plant species

Question 18

systematic disadvantages

Answer 18

species that don’t fall on line may be missed out (underestimation of areas biodiversity, sample doesn’t become representative)

Question 19

sampling technique for plants

Answer 19

place quadrat on sample sites (depends on sampling method
identify
plants in quadrat using key
measure/estimate abundance of each species

Question 20

ways of measuring / estimating abundance of a species

Answer 20

abundance scale (ACFOR)
estimate percentage cover
measure percentage cover using point frame

Question 21

point frame

Answer 21

frame with 10 needles
place down 10 times on quadrat
each plant touching pin has 1% cover

Question 22

ACFOR

Answer 22

Abundant
Common
Frequent
Obvious
Rare
not very quantitative, very subjective

Question 23

model answer for method of sampling plants

Answer 23

choose sampling method and select areas to be sampled
place quadrat
identify plant species in quadrat (using key)
record presence/absence of each species in each quadrat
estimate percentage cover (using point frame)
repeat to show repeatability and to identify anomalies
extrapolate data to estimate biodiversity

Question 24

sampling animals facts

Answer 24

animals move so need to be trapped (smaller animals) or sampled visually (larger animals without trapping)

Question 25

equipment needed when sampling habitat

Answer 25

suitable clothing and footwear for habitat sampling apparatus clipboard, pens and paper to record observations keys appropriate to area to identify organisms camera/smartphone to record specimens and grid location

Question 26

mark-and-recapture technique

Answer 26

``` capture sample of animals mark each individual in harmless way (C1) release marked animals capture another sample (C2) number of already marked animals = C3 population estimate = (C1xC2)/C3 ```

Question 27

factors affecting population estimate found using mark-and-recapture

Answer 27

animals learning trap is harmless and contains food | animals not liking experience and keep away from traps after first capture

Question 28

pond/sweep nets

Answer 28

sweep nets in wide arcs to catch animals identify and count on white background used for small animals/insects living in water/low vegetation

Question 29

pooter

Answer 29

sucks up animals into small container to stop them flying away used for small animals/insects once caught in sweep nets/from trees

Question 30

from trees

Answer 30

hit tree branches with stick to knock off animals into white tray/paper to identify and count used for small animals/insects in trees

Question 31

pitfall trap

Answer 31

container buried in soil (just below soil), small animals / insects fall into it water / stunning chemical used to stop them crawling out should be sheltered in rain used for small animals / insect on ground

Question 32

Tullgren funnel

Answer 32

leaf litter placed on mesh light dries out leaf litter animals go down, fall through mesh into a collecting jar small animals / insects from leaf litter

Question 33

light trap

Answer 33

UV light attracts insects which fall into alcohol in trap | insects attracted to light at night

Question 34

Longworth trap

Answer 34

bait put in trap, snaps shut behind animals leaves animal unharmed can be marked, released and recaptured to estimate population size trapping small animals e.g. mice

Question 35

surveying frequency of plants

Answer 35

use similar sampling method as before (quadrat) | calculate percentage cover

Question 36

measuring density of animals in a habitat

Answer 36

larger animals = observation smaller animals = mark-and-recapture technique tiny animals in soil = count individuals animals in water = net to sift through body of water and mud then count

Question 37

Simpson’s index of diversity (D)

Answer 37

measure of diversity in a habitat takes into account species richness and evenness D = 1 - (sum of all (number of one species/total number of all species in the habitat)^2)

Question 38

Interpreting Simpson’s index of diversity

Answer 38

close to 1 = more biodiversity in habitat suggests habitat is home to wide variety of different species changes to one species won’t impact many individuals (in proportion to total number of individuals) further from one = less biodiversity in habitat suggest habitat dominated by few species small change to one species could damage or destroy whole habitat

Question 39

measuring genetic diversity

Answer 39

more alleles of one locus = more observable variation between individuals in a same species calculate percentage of polymorphic gene loci

Question 40

polymorphic gene loci

Answer 40

have 2 or more alleles

Question 41

locus definition

Answer 41

position of specific gene on chromosome

Question 42

human factors for biodiversity

Answer 42

human population growth agriculture climate change

Question 43

how human population growth affects biodiversity

Answer 43

clear out land for farming extract and use natural resources (destroys habitats) e.g. hunting/fishing, fossil fuels burning of fossil fuels for more energy (pollution)

Question 44

how agriculture affects biodiversity

Answer 44

monoculture: reduces genetic biodiversity (only one strain of species), crops more likely to die out of habitat factors suddenly change selective breeding: reduces genetic biodiversity as ignores other traits in place for a select few desired traits, specific breeds become rare or die out land cleared out for farming space

Question 45

genetic erosion definition

Answer 45

loss of alleles, reducing genetic diversity of species

Question 46

monoculture definition

Answer 46

when only one strain of a crop is farmed | makes harvesting of crops easier and cheaper

Question 47

how climate change affects biodiversity

Answer 47

changes in temperature and rainfall, caused by human activity species with low genetic diversity may go extinct (unable to adapt) may be forced to migrate (not always possible) diseases may migrate, harming other ecosystems monocultures (low genetic diversity) won’t be able to survive

Question 48

extinction definition

Answer 48

when the last living member of a species dies so species ceases to exist

Question 49

reason to maintain biodiversity

Answer 49

ecological reasons economic reasons aesthetic reasons

Question 50

ecological reasons for maintaining biodiversity

Answer 50

``` plants form habitats for other organisms interdependence (loss of one species affects other species, part of food chain in ecosystem) keystone species (have disproportionate effect on habitat relative to population size) genetic resource for genetic engineering, selective breeding, medicine ```

Question 51

economic reasons for maintaining biodiversity

Answer 51

plant biodiversity encourages recycling of nutrients in soil , better ability to grow crops monocultures deplete soil deforestation can cause flooding (damages crops/buildings) wood used for furniture making could be a tourist attraction could be a source of medicine/scientific research

Question 52

conservation ex situ definition

Answer 52

conserving an endangered species by activities that take place outside its normal environment

Question 53

when conversation ex situ is necessary

Answer 53

natural habitat destroyed/under threat by climate change/human activity population in natural habitat very low if reproduction in wild is difficult (low numbers) breeding programmes allows increase in population size of species

Question 54

how conservation ex situ helps conservation of plants and animals

Answer 54

breeding ex situ maintains genetic diversity (if done properly) allows protection from competition, grazes/poachers allows protection from diseases

Question 55

how to set up captive breeding programmes for animals

Answer 55

collect animals from several different locations increases genetic variation if geographical variation maintained reduces risk of inbreeding, of losing all individuals to specific disease minimise stress during capture and captivity zoos have data on which individuals are related zoos can exchange sperm and artificially inseminate for lower likelihood of inbreeding, better genetic variation

Question 56

advantages of ex situ for animals

Answer 56

health can be monitored, diseases treated young hand reared (lowers chance of mortality of young) provision of breeding mates controlled protection from diseases, predation, hunting competition reduced between individuals

Question 57

disadvantage of ex situ for animals

Answer 57

``` expensive often don’t breed successfully (captive stress, no compatible mate, altered breeding cycle) space limited (limit number of individuals, less genetic diversity and variation, may lead to inbreeding) may be difficult to reintroduce species to wild ```

Question 58

why reintroduction of species into wild may be difficult

Answer 58

animals too tame (not afraid of humans/poachers) unable to reintegrate to wild population difficult to find food for themselves may face predation habitats may be destroyed

Question 59

conservation in situ definition

Answer 59

conserving a species in its normal habitat and attempting to minimise human impact on natural environment and protecting natural environment

Question 60

measures to help preserve species in wild

Answer 60

``` ban hunting create protected reserves proving breeding sites prevent habitat destruction monitoring species with tagging feeding programmes educate tourists on not feeding wild animals, not dropping litter promotion of ecotourism (generate money to help preservation, create sperm + egg banks) ```

Question 61

advantages of in situ

Answer 61

cheaper than ex situ (conditions + food required fir survival may already be present) species already well adapted to habitat no special previsions needed to be made can create protected reserves

Question 62

advantages of protected reserves

Answer 62

can ensure sustainable use of environment (land and resources) allows for scientific research of ecosystem permanently protects biodiversity in area creates areas of interest for tourists

Question 63

disadvantages of conservation in situ

Answer 63

threats to survival of species may be present human activity may threaten species (e..g hunting, deforestation) disease could threaten survival of species species could be outcompetes by other species

Question 64

CITES and its aims

Answer 64

Convention on International Trade in Endangered Species of Wild Fauna and Flora prevent trade of endangered species ensure trade doesn’t endanger wild populations prohibit commercial trade in wild plants allows some trade of less endangered plants and animals allow trade in artificially propagated plants

Question 65

how CITES helps to save endangered species

Answer 65

countries in agreement make poaching illegal ban trade of endangered species increase cooperation between countries increase awareness of impact of illegal trade

Question 66

Rio convention on Biological Diversity

Answer 66

International agreement by 150 governments promotes sustainable development recognises human needs for food, medicine, land, clean environment as well as maintaining biodiversity

Question 67

Rio convention of Biological Diversity aims

Answer 67

sustainable use of organisms/habitats/ecosystems share genetic resources and access to scientific knowledge promoting ex situ conservation methods international cooperation of biodiversity issues raising profile of biodiversity with governments / general public

Question 68

advantages of seed banks / botanic gardens

Answer 68

seeds collected from wild population won’t impact wild population too much (as produced in large numbers) seeds stored in protected surroundings compact so can be stored in large numbers plants can breed asexually can be used for research or reintroduction to the wild

Question 69

disadvantages of botanic gardens/seed banks

Answer 69

may be difficult to fund publicly collecting wild seeds always causes some disturbance collected samples may not have representative level of genetic diversity seeds collected from one area genetically different from another area, may not succeed in different areas seeds stored for long time may not be viable asexual breeding reduces generic diversity (genetically identical offspring) research done on small sample may not be valid for whole species

Question 70

how seeds stored

Answer 70

very dry / freezing conditions | regularly checked if seeds can germinate (as they deteriorate over time)

Question 71

Countryside Stewardship Scheme

Answer 71

introduced in England 1991 applied to land not to be in an environmentally sensitive area paid farmers to enhance and conserve English landscapes

Question 72

Countryside Stewardship Scheme aims

Answer 72

improve natural beauty and diversity in countryside enhance, restore and recreate landscapes, wildlife habitats and historical features improve opportunities for public access

Question 73

Environmental Stewardship Scheme

Answer 73

replaced CSS in 2005 | funds and advises farmers and other land managers to environmentally manage their land

Question 74

Environmental Stewardship Scheme aims

Answer 74

converse, enhance and promote countryside by: look after wildlife, species and habitats retain traditional character of land protect historic features and natural resources traditional livestock and crops conserved opportunities for people to visit and learn about countryside