Chapter 11 - Biodiversity

Question 1

Biodiversity

Answer 1

➜ a study of all the variation that exists within and between all forms of life
➜ looks at the range and variety of genes, species and habitats within a particular region
➜ assessed at 3 diff levels:
- number and range of different ecosystems and habitats
- number of species and their relative abundance
- genetic variation within species

Question 2

Ecosystem or habitat diversity

Answer 2

➜ the range of different ecosystems or habitats within a particular area or region
➜ large number of diff habitats = likely to have high biodiversity

Question 3

Species diversity

Answer 3

➜ very high number of different species = species rich
➜ the evenness of abundance across the different species present = species evenness
➜ ecosystems with high species diversity are usually more stable

Question 4

Genetic diversity

Answer 4

➜ diversity of alleles and genes in the genome of species
➜ individuals in species may have same genes but not same alleles
➜ measured by working out the proportion of genes that have more than one form (allele) and how many possible alleles each gene has
➜ can also be observed within a single population - can help population to adapt to abiotic (temp etc) or biotic (new predator/disease) factors
➜ limited in populations that are very small or isolated = cuz inbreeding occurs

Question 5

Sampling

Answer 5

➜ method of investigating the abundance and distribution of species and populations
➜ 2 types: Random, Non Random

Question 6

Random

Answer 6

➜ positions of the sampling points are completely random or due to chance
➜ beneficial because it means there will be no bias
➜ used to estimate the distribution and abundance of species (distribution = describes how it is spread throughout the ecosystem) (abundance = the number of individuals of that species)

Question 7

Sweeping nets:

Answer 7

large, strong nets with a fine material (very small holes) that are used to catch flying insects and insects that live in long grass by sweeping the net back and forth through the grass

Question 8

Pitfall traps:

Answer 8

these are cans or jars that are buried in the ground that are used to catch ground-dwelling (often nocturnal) insects and other invertebrates as they fall into the trap

Question 9

Pooters:

Answer 9

these are small plastic or glass containers with two tubes sticking out that are used to suck up small insects and other small invertebrates. The first tube is placed over the insect and the second tube is used by the scientist to create suction

Question 10

Tullgren funnel:

Answer 10

these are funnels with a light bulb above and a container below that are used to collect invertebrates that live in leaf litter or soil. The leaf litter or soil is placed in the funnel and the light and heat forces the invertebrates to move down until they drop into the container

Question 11

Kick-sampling:

Answer 11

this technique is used to catch freshwater invertebrates living in streams or rivers. A net in placed on the stream-bed so that the water is flowing into it and the stream-bed just above the net is churned up by the scientist (using their foot) for a set period of time. The invertebrates are carried by the stream into the net

Question 12

non-random

Answer 12

➜ the positions of the sampling points are chosen by the person carrying out the sampling
➜ possibility that the person choosing could show bias
➜ Individuals may deliberately place the quadrats in areas with the least species as these will be easier and quicker to count
➜ unrepresentative of the whole area

Question 13

Opportunistic sampling

Answer 13

➜ picking and choosing sampling locations based on various non-random factors

Question 14

Stratified sampling

Answer 14

➜ matching the number of sampling locations in a particular habitat with the relative proportion of area that habitat covers in the whole area being studied

Question 15

Systematic sampling

Answer 15

➜ used when there is a clear change in the physical conditions across the area being studied
➜ e.g change in soil pH
➜ methods using transects can show species distribution
➜ transect is a line represented by a measuring tape, along which sample are taken

Question 16

Line Transect

Answer 16

➜ Lay out a measuring tape in a straight line across the sample area
➜ equal distances along the tape, record the identity of the organisms that touch the line (e.g every 2m)
➜ produces qualitative data

Question 17

Belt Transect

Answer 17

➜ Place quadrats at regular intervals along the tape and record the abundance or percentage cover of each species within each quadrat
➜ produces quantitative data

Question 18

Species richness

Answer 18

➜ measure of the number of different species within a given area
➜ can be a misleading indicator as it does not take into account the number of individuals of each species

Question 19

Species evenness

Answer 19

➜ measure of the relative abundance of the different species within a given area

Question 20

Assessing Genetic Diversity

Answer 20

➜ Genetic diversity within a single population can also be observed
➭ by looking at the proportion of polymorphic gene loci (number of loci that have two or more alleles)
➭ by looking at the proportion of the population that is heterozygous for any specific gene locus
➭ Allele richness (the number of different alleles that exist for specific genes)

Question 21

Genetic polymorphism

Answer 21

➜ occurs when there are two or more alleles present at a single loci

Question 22

monomorphic locus

Answer 22

➜ one that does not have multiple alleles

Question 23

polymorphic locus

Answer 23

➜ one that has multiple alleles

Question 24

equation for calculating the proportion of polymorphic gene loci (P) is:

Answer 24

P = number of polymorphic gene loci ÷ total number of loci investigated

Question 25

Limitations of P

Answer 25

➜ does not illustrate the allele richness of a breed or species
➜ other methods such as comparing amino acids or DNA sequences can be more effective

Question 26

why population of hooman grow?

Answer 26

➜ Improved technology leading to an abundance of food = increase in birth rate
➜ Improved medicine, hygiene and health care = decrease in death rate

Question 27

Why hooman pop growing bad?

Answer 27

➜ use many resources from earth like land, water, wood and fossil fuels so natural resources decrease
➜ harmful effect on many aspects of the environment, including aquatic and terrestrial ecosystems, and our atmosphere and climate
➜ damage to these ecosystems is negatively impacting the species and habitats contained within them
➭ main factors affecting biodiversity today are:
∘ Habitat destruction
∘ Overexploitation
∘ Hunting
∘ Agriculture
∘ Climate change

Question 28

Habitat destruction

Answer 28

➜ cleared for agriculture/industry blahblah
➜ Habitat loss - organisms completely lose their habitats
➜ Habitat fragmentation - habitats are divided into small areas so populations living within these separated
➜ Deforestation
➜ Coral reefs - dynamite to catch fish wtaf
➜ Sea beds - trawling (nets dragged across floow)

Question 29

Overexploitation

Answer 29

➜ resources are being used up faster than they can be replaced
➜ e.g deforestation - not enough being replanted
➜ e.g fish stocks - knock on effect on marine mammals

Question 30

Hunting

Answer 30

➜ another form of overexploitation with non farmed species being hunted too much
➜ hunting for ‘bush meat’

Question 31

Agriculture

Answer 31

➜ after WW2 - massive change in food production
➜ Farms became more specialised so they grew only one crop or raised one type of livestock (monoculture) = lower levels of biodiversity
➜ switch to growing cereal crops rather than vegetables
➜ fields were made bigger for machinery
➜ land was made suitable by draining wetland and filling in ponds
➜ use of fertilisers 🡅 - leach into waterways causing eutrophication (excess enrichment of nutrients) so many fish species die
➜ use of pesticides massively 🡅 = also kill many non-target species, including important insect pollinators like bees

Question 32

Climate change

Answer 32

➜ Human-caused climate change is causing weather patterns to change and the frequency of extreme weather events
➜ e.g hurricanes, typhoons, floods and droughts, to increase
➜ Global warming
➜ Increasing CO₂ - lots dissolved in seawater so 🡇 pH = bad cuz organisms need calcium carbonate
➜ 🡅 ocean temp = coral bleaching

Question 33

Why maintain biodiversity?

Answer 33

∘ Ecological
∘ Economic
∘ Aesthetic
∘ Social
∘ Moral/ethical
∘ Environmental
∘ Agricultural

Question 34

Ecological reasons

Answer 34

➜ Biodiversity has a major effect on the stability of an ecosystem
➜ A more diverse ecosystem is better able to survive and adapt to environmental changes or threats
➜ Communities have keystone species = have a larger impact on ecosystem that others due to knock on effects

Question 35

Economic reasons

Answer 35

➜ medicines used today have originated from plants, fungi and bacteria
➜ ecotourism - major income for many countries
➜ Ecosystems have also made major contributions to the field of science and technology

Question 36

Aesthetic reasons

Answer 36

➜ Humans find great joy and pleasure in the beauty of nature
➜ provides inspiration for creatives such as photographers, poets, musicians and artists

Question 37

Social reasons

Answer 37

➜ people enjoy spending time in the natural environment for relaxation
➜ activities to do in nature - birdwatching, walking, hiking

Question 38

Moral & ethical reasons

Answer 38

➜ people believe that humans have a moral obligation to prevent the loss of biodiversity that results from human activities
➜ humans share the planet with millions of others species and they have no right to cause the extinction of other species
➜ humans are the most intelligent species on the planet the responsibility falls upon their shoulders to protect and value all of the organisms on the planet

Question 39

Environmental reasons

Answer 39

➜ plants absorb CO₂ from the atmosphere and help to reduce the greenhouse effect and climate change
➜ Microorganisms digest and break down the masses of organic waste that are produced by larger organisms
➜ transpiration of plants contribute to the water cycle
➜ Plants are producers in food web

Question 40

Agricultural reasons

Answer 40

➜ crops that humans grow are very uniform with low genetic diversity
➜ wild relatives of crops can provide a source of genetic diversity to rescue crops that are affected by disease or other disasters

Question 41

National parks

Answer 41

➜ human access is strictly controlled
➜ industrial activities (agriculture or building) is tightly regulated
➜ hunting is limited or prohibited

Question 42

Marine parks

Answer 42

➜ protected areas of water
➜ restrictions to prevent overfishing and pollution like making fishing illegal without license

Question 43

Public engagement

Answer 43

➜ National and Marine parks can attract thousands of tourists each year which increases money and awareness for the conservation effort
➜ jobs for local community near the parks
➜ profits used to improve health or education to illustrate the benefits of parks

Question 44

Zoos and captive breeding

Answer 44

➜ zoos = can help scientific research
➜ problems:
- captive breeding of small species populations can reduce genetic diversity
- Certain animal species will not breed in captivity
- not all zoos can provide adequate habitats
➜ educate public

Question 45

Botanic gardens

Answer 45

➜ use cuttings and seeds collected from the wild to establish a population of the endangered species in captivity
➜ captive population can be used in the future for reintroduction into habitats where they have become rare
➜ research
➜ educate public

Question 46

Storing genetic material for Conservation

Answer 46

➜ Frozen zoos - store genetic material like eggs, sperm, tissue samples etc at low temp = maintain gene pool, bring back extinct species
➜ seed bank - dry and store seeds = maintain gene pool, bring back extinct species, seeds can only be stored for so long tho and some cant be frozen

Question 47

IUCN - International Union for the Conservation of Nature

Answer 47

➜ they assess the conservation status of animal and plant species around the world
➜ has their own classification system
➜ several different categories and levels that a species can fall into depending on their population numbers and the threats and risks to those populations

Question 48

CBD - Convention on Biological Diversity

Answer 48

➜ signed at the Earth Summit in Rio de Janeiro, 1992
➜ Goals:
- conservation of biological diversity by use of a variety of different conservation methods
- sustainable use of biological resources
- fair and equitable sharing of benefits arising from genetic resources

Question 49

CITES - Convention on International Trade in Endangered Species of Wild Flora and Fauna

Answer 49

➜ global agreement that has been signed by over 150 countries
➜ aim is to control the trade of endangered species and their associated products
➜ categorizes endangered and vulnerable species into three appendices:
∘ Appendix I : species that are endangered and face the greatest risk of extinction
∘ Appendix II: species that are not currently endangered or facing extinction, but will be unless trade is closely controlled
∘ Appendix III: species included at request of the country that is regulating trade of the species and trying to prevent its overexploitation
➜ Trading regulations for each appendix:
∘ appendix I: all trade in the species and their associated products is banned
∘ appendix II: trade is only granted if an export permit has been issued by the involved countries
∘ appendix III: permits are required for regulated trade but its easy to get

Question 50

CSS - Countryside Stewardship Scheme

Answer 50

➜ scheme dating back to the 1980s that provided funding to farmers and private landowners in England who used environmental management strategies to protect and increase the natural biodiversity on their land
➜ scheme was replaced by the Environmental Stewardship Scheme (ESS) in 2005
➜ To qualify:
∘ must provide and protect valuable wildlife habitats such as ponds, hedgerows and buffer zones surrounding farmed areas
∘ ensure land is managed well, maintaining traditional character
∘ protect any natural resources or historic features on their land
∘ conserve any traditional crops or livestock present
∘ provide visitor opportunities so people can learn about the countryside and how important it is in sustaining biodiversity