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A-Level Biology > Biodiversity > Flashcards

Biodiversity Flashcards

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1
Q

What is biodiversity?

A

Variety of living organisms present in an area ; this includes all living organisms

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2
Q

Why is biodiversity important?

A

Maintaining a balanced ecosystem for all organisms - all species are interconnected as they could provide habitats, food cycles, help in decomposing dead plants and animals to return nutrients to the soil

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3
Q

Why do we rely on balanced ecosystems?

A

As they provide us with the food, oxygen and other materials that we need to survive ; many human activities such as farming and clearing land for housing can lead to a reduction in biodiversity

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4
Q

How does biodiversity vary across the globe?

A

Tropical/moist regions have the most biodiversity - warm all year round
Temperate region (U.K.) warm summers and cold winters have less
Extreme environments - very cold Arctic or very dry deserts have the least biodiversity.
Closer a region is to the Equator, greater the biodiversity

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5
Q

Why do we measure biodiversity?

A

Important role in conservation - informs scientists of the species that are present thus providing a baseline for the level of biodiversity in an area and then you can measure the change to an environment (disease/human activity/climate change)

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6
Q

What is an EIA?

A

Environmental Impacts assessment which is taken before big infrastructure projects - predicts the positive and negative effects of a project on the biodiversity in that area

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7
Q

3 levels that biodiversity can be studied at

A

Habitat biodiversity
Species biodiversity
Genetic biodiversity

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8
Q

Habitat biodiversity

A

Number of different habitats found within an area - each habitat can support a number of different species thus greater species biodiversity is as a result of greater habitat biodiversity. U.K. has a higher habitat biodiversity than America which is covered almost entirely by an ice sheet - very few species live in this region. On a smaller scale - countryside that is habitat rich (hedges/rivers) will be more species rich than farmed countryside with large ploughed fields which make up a single uniform habitat

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9
Q

What is species biodiversity composed of?

A

Species richness and species evenness

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10
Q

What is species richness!

A

Number of different species living in a particular area

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11
Q

What is species evenness?

A

Comparison of the number of individuals of each species living in an community

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12
Q

What is a community?

A

All the populations of living organisms in a particular habitat

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13
Q

Cornfield vs Grass Meadow

A

May both contains the same number of species (species richness) by in the cornfield, corn will make up 95% of the community with the remaining 5% made up by other organisms including insects mice etc. in the grass meadow the species will be more balanced in their populations.

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14
Q

Genetic biodiversity

A

Variety of genes that make up a species - humans have about 25000 genes but some other species may have 400000 (flowering plants) ; for many genes there are different versions (alleles) which leads to genetic biodiversity within a species

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15
Q

What can genetic biodiversity lead to?

A

Intraspecies - it can lead to different characteristics being exhibited ; some genes are the same for all breeds of dog which define the organism as a dog but some genes have many alleles that code for the wide variation in characteristics seen between different breeds of dog (coat colour and length)

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16
Q

What does greater genetic biodiversity lead to?

A

Allows a species to better adapt to a changing environment - if there are any adverse changes then the species can cope and also is more likely to result in individuals who are resistant to disease (not good for us if those individuals are bacteria)

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17
Q

Why is sampling used?

A

Impossible to measure all of the organisms present in an area

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18
Q

What is sampling?

A

Taking measurements of a limited number of individual organisms present in a particular area - estimate the number of organisms in an area without having to count them all ; number of individuals of a species present in an area is known as the abundance of the organism.

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19
Q

What can you do with a sample

A

Use the results to make generalisations/estimates about the number of organisms - distribution of species or measured characteristics throughout the entire habitat ; CAN BE DONE IN TWO WAYS : NON-RANDOM OR RANDOM

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20
Q

What is random sampling?

A

Selecting individuals by chance - in a random sample, each individual in the population has an equal likelihood of selection. Random number tables/computers are used so that there is no involvement in deciding which organisms to investigate

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21
Q

How to take a random sample at a grass verge?

A

Mark out a grid on the grass using two tape measures laid at right angles
Use random numbers to determine the x and y coordinate on the grid
Take a sample at each of the coordinate pairs generated

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22
Q

What is non-random sampling

A

Alternative sampling method where the sample is not chosen at random - it can be opportunistic/stratified or systematic

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23
Q

Opportunistic (non-random sampling)

A

Uses organisms that are conveniently available - least representative of the population thus weakest form of sampling

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24
Q

Stratified (non-random sampling)

A

Some populations can be divided into a number of strata based on a particular characteristic - population can be separated into males and females and then a random sample is taken from each of these strata proportional to its size

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25
Q

Systematic (non-random sampling)

A

Different areas within an overall habitat are identified which are then sampled separately - systematic sampling may be used to study how plant species change as you move inland from the sea. It is carried out using a line or a belt transect

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26
Q

Line vs belt transect

A

Line involved marking a line along the ground and taking samples at specified points ; this can include describing all of the organisms which touch the line or distances of samples from the line
Belt transect - two parallel lines are marked and samples are taken of the area between the two lines

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27
Q

Reliability?

A

Sample is never entirely representative of the organisms present in a habitat - may be due to sampling bias or chance

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28
Q

Sampling bias

A

Selection process may be biased ; may be by accident or may occur deliberately - you may inadvertent choose to sample an area with more flowers because it looks more interesting - this can be reduced by random sampling where human involvement is minimum

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29
Q

Chance?

A

Organisms selected may or may not be representative of the whole population - for example 5 worms collected may be the 5 longest worms. Chance can never be completely removed from the process but it’s effect can be minimised by using a large sample size - greater the number of individuals studies, the lower the probability that chance will influence the result. THUS MAKE SURE TO HAVE LARGE SAMPLE SIZE

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30
Q

At each sampling point?

A

Use more than one technique to collect a range of data

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31
Q

Precaution with living organisms

A

They must be handled carefully and for as short a time period as possible - as soon as they have been identified/counted and measured then they must be released into the habitat where they were collected

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32
Q

Pooter

A

Used to catch small insects by sucking on a mouthpiece - insects are drawn into the holding chamber via the inlet tube and a filter before the mouthpiece prevents them from being sucked into the mouth

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33
Q

Sweep nets

A

Catch insects in areas of long grass

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34
Q

Pitfall traps

A

Small, crawling invertebrates such as beetles/spiders/slugs - hole is dug in the ground which insects fall into and it must be deep enough so that they do not crawl out
MUST BE COVERED with a roof structure propped above so that the trap does not fill with rainwater
Traps are kept overnight so that nocturnal species are also sampled

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35
Q

Tree beating

A

Take samples of invertebrates living in a tree/bush ; large white cloth is stretched out under the tree and the tree is shaken/beaten to dislodge the invertebrates. The animals will fall onto the sheet where they can be collected and studied

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36
Q

Kick sampling

A

Used to study the organisms living in a river - river bank and bed is kicked for a period of time to disturb to substrate and a net is held just downstream for a set period of time in order to capture any organisms released into the flowing water

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37
Q

Sampling plants

A

Plants are sampled using a quadrat which can also be used to pinpoint an area in which the sample of plants should be collected - it can also be used to sample slow-moving animals like limpets, barnacles and mussels

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38
Q

Point quadrat (1 of the two types of quadrat)

A

Consists of a frame containing a horizontal bar - at set intervals along the bar, long pins can be pushed through the bar to reach the ground - each species the plant touches is recorded

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39
Q

Frame quadrat

A

Consists of a square frame divided into a grid of equal sections - the type and number of species within each section of the quadrat is recorded

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40
Q

To collect the most valid representative sample?

A

Quadrats should be used following a random sampling technique

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41
Q

To study how the presence and distribution of organisms across an area of land varies

A

Quadrats can be placed systematically along a line or belt transect

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42
Q

How to measure species richness?

A

Biodiversity species richness is a measure of the number of different species living in a specific area ; use a combination of the techniques described above to try to identify all the species present in a habitat and a list should be compiled of each species identified thus the total number of species can be calculated

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43
Q

How to enable scientists to accurately identify organisms?

A

Identification keys are used these may contain a series of questions/pictures to classify an organism into a particular species

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44
Q

How to measure species evenness

A

Species evenness refers to how close in numbers the populations of each species in an environment are - 50 organisms found and 20 are wood lice, 15 are spiders and 15 are centipedes ; this community is quite evenly distributed between species

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45
Q

Purpose of a frame quadrat

A

Sample the population of plants living in a habitat
Density
Frequency
Percentage cover

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46
Q

Density

A

If individual large plants can be seen clearly, count the number of them in a 1m by 1m square quadrat and this will give density/m^2 - this is an ABSOLUTE MEASURE NOT ESTIMATE

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47
Q

Frequency (estimate)

A

Individual members of a species are hard to count ; (grass/moss) - use small grids within a quadrat to count the number of squares a particular species is present in. If clover is present in 65/100 squares - the frequency of its occurrence is 65%

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48
Q

Percentage cover (use of frame quadrat)

A

Lots of data can be collected quickly - useful when a particular species is abundant/difficult to count and is simply an estimate by eye of the area within a quadrat

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49
Q

Why should samples be taken at a number of different points?

A

Large number of samples = more reliable the results - then calculate the mean of individual quadrat results to get an average value for a particular organism per m^2. Total value = mean value * m^2 of total area

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50
Q

Difficulty to determine animal population size accurately?

A

Animals are constantly moving/stay hidden so capture-mark-release-recapture is used to estimate a population size

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51
Q

How does capture-recapture work?

A

Organisms are marked and then released back into the community - time is allowed for the organism to redistribute themselves throughout the habitat before another sample is collected. Can compare the number of marked vs unmarked in second sample, scientists can estimate population size - GREATER THE NUMBER OF MARKED INDIVIDUALS = SMALLER THE POPULATION

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52
Q

How can species evenness then be measured through capture recapture?

A

Compare the total number of each organism present - populations of plants or animals that are similar in size or density represent an even community and hence a high species evenness. Species evenness can also be expressed as a ratio between the numbers of each organism present

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53
Q

What are abiotic factors?

A

Non-living conditions in a habitat that have a direct effect on the living organisms that reside there - examples include the amount of light/water available

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54
Q

How do you get around the fact that abiotic factors play a role in measure organisms?

A

Draw conclusions about the organisms present and the conditions they need for survival - they measure conditions at every sampling point

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55
Q

Wind speed?

A

Anemometer - m s^-1

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56
Q

Light intensity

A

Light meter (lx)

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57
Q

Relative humidity

A

Humidity sensor mg dm^-3

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58
Q

pH

A

pH probe pH

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59
Q

Temperature

A

Temperature probe (degrees Celsius)

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60
Q

Oxygen content in water

A

Dissolved oxygen probe mg dm^-3

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61
Q

Advantages of measure abiotic factors using sensors quickly?

A

Rapid changes can be detected
Human error in reading is reduced
High precision can often be achieved
Data can be stored/tracked on a computer/storage device

62
Q

Calculations involved?

A

Measure of species diversity - this is proportional to the stability of the ecosystem so the greater the species diversity the greater the stability - most stable communities have large number of fairly evenly distributed species

63
Q

Pollution effect?

A

Reduces biodiversity - as a result of harsh conditions, a few species tend to dominate and so monitoring biodiversity is a useful tool in successful conservation and environmental management

64
Q

Problem with counting the number of species?

A

Does not take into account the number of individuals present - 2 daisies = 1000 buttercups in terms of dominance

65
Q

Simpsons Index of Diversity (D)

A

Good measure of biodiversity as it takes into account both species richness and species evenness

66
Q

Formula for Simpson’ Index of Diversity (D)

A

D = 1- sum of ((total number of organisms of a particular species)/(total number of organisms of all species))^2

67
Q

Key thing about D

A

Simpsons Index always ends up with a value between 0 and 1 where 0 represents no diversity and 1 represents infinite diversity - HIGHER THE VALUE = MORE DIVERSE

68
Q

Number of successful species in Low vs High bd

A 
Low = relatively few
High = a large number
69
Q

Nature of environment in Low Bd vs High Bd

A

Low Bd - stressful/extreme with relatively few ecological niches
High Bd - relatively benign/not stressful with more ecological niches

70
Q

Adaptions of species Low Bd vs High Bd

A 
Low = relatively few species with very specific adaptations
High = many species often with few specific adaptations
71
Q

Food web low Bd vs high Bd

A 
Low = relatively simple
High = complex
72
Q

Effect of a change to the environment on ecosystem

A

Low Bd = major effect

High Bd = relatively small effect

73
Q

Why is it important to conserve habitats with low biodiversity?

A

In order to conserve those rare species that may be too specialised to survive elsewhere - they are highly adapted to the extreme environment of the habitat.

74
Q

WORK THROUGH EXAMPLE AND QUESTIONS ON 280 AND 281

A

Done 😊

75
Q

In isolated populations - captive breeding programme?

A

Genetic biodiversity is often reduced - individuals may suffer from a range of problems associated with in-breeding

76
Q

What do scientists calculate genetically?

A

Genetic biodiversity of a population of a species - gene pool to monitor the health of the population and ensure its long-term survival

77
Q

Within a species

A

Individuals have very little variation within their DNA

78
Q

How do genes vary in a species?

A

All members have the same genes but they may have different versions of some of these genes - these different versions are called alleles and the differences in alleles creates genetic biodiversity within the species ; more alleles = more genetically biodiverse

79
Q

Species with greater genetic biodiversity?

A

Able to adapt to changes in their environment and thus less likely to become extinct - there are likely to be organisms that carry an advantageous allele which enables them to survive in altered conditions

80
Q

Example of when genetic biodiversity helps?

A

A potentially fatal disease is introduced and all organisms are killed unless individuals carry resistance - these can then survive and reproduce, survival of the fittest (the species)

81
Q

What does genetic biodiversity increase depend on?

A

Number of possible alleles must also increase

82
Q

How can genetic biodiversity be increased?

A

Mutations in the DNA of an organism, creating a new allele
Gene flow - interbreeding between members of different populations as a result of migration and alleles are transferred between the two populations

83
Q

How does genetic biodiversity decrease?

A

Number of possible alleles must also decrease
Selective breeding - artificially selecting only a few species to breed due to their advantageous characteristics (breeding of pedigree animals/food crops)

84
Q

How does captive breeding decrease genetic biodiversity

A

Only a small number of captive individuals of a species are available for breeding - wild population is endangered/extinct

85
Q

How do rare breeds affect genetic biodiversity?

A

Selective breeding to begin with
Characteristics become less popular/unfashionable
Numbers of the breed fall catastrophically and when only a small number of individuals of a breed remain the genetic diversity is low and this can cause serious problems when trying to restore numbers yet maintain breed characteristics

86
Q

Artificial cloning on genetic biodiversity?

A

Asexual reproduction - using cuttings to clone a farmed plant

87
Q

Natural selection on genetic biodiversity

A

Species will evolve to contain primarily the alleles which code for advantageous characteristics - over time alleles coding for less advantageous characteristics will be lost from a population or only remain in a few individuals

88
Q

Genetic bottlenecks on genetic biodiversity

A

Where few individuals within a population survive an event/change (disease/habitat destruction) - reducing the gene pool and thus only the alleles of the surviving population are available to be passed on to offspring

89
Q

Founder effect on genetic biodiversity

A

A small number of individuals create a new colony - geographically isolated from the original so gene pool for this new population is small

90
Q

Genetic drift on genetic biodiversity

A

Random nature of alleles being passed on from parents to their offspring - frequency of occurrence of an allele will vary and in some cases the existence of a particular allele can disappear from a population altogether

91
Q

How do scientists quantify genetic biodiversity?

A

Measuring polymorphism - polymorphic genes have more than one allele ; different alleles exist for the immunoglobulin gene which plays a role in determining human blood type

92
Q

Monomorphic?

A

Most genes are not polymorphic - these genes have a single allele for each gene, ensuring that the basic structure of individuals within a species remains consistent

93
Q

How to measure the genetic biodiversity numerically?

A

Proportion of polymorphic gene loci = number of polymorphic gene loci/total number of loci

94
Q

What are loci?

A

Refers to the position of the gene on a chromosome

95
Q

Greater the proportion of polymorphic gene loci?

A

Greater the genetic biodiversity

96
Q

Why is maintaing biodiversity important?

A

Preserving a balanced ecosystem for all organisms as species are interconnected within an ecosystem ; removal of one species can have a profound effect on others - we as humans rely on the ecosystem a lot for food/wood/oxygen

97
Q

Human influence on biodiversity?

A

To create enough space for housing/industry/farming to support this exponentially increasing population - humans are disrupting the ecology of many areas

98
Q

3 main biodiversity problems humans are responsible for

A

Deforestation - permanent removal of large areas of forest to provide wood for building and fuel known as logging and to create space for infrastructure
Agriculture - increasing amount of land has to be farmed in order to feed the growing population ; large amounts of land being cleared and in many cases planted with a single crop (MONOCULTURE)
Climate change - release of CO2/other pollutants from burning fossil fuels increases global temperatures

99
Q

Forms of pollution

A

Chemical pollution of waterways/improper waste disposal/packaging as littering

100
Q

Deforestation roots?

A

Forest fires can occur naturally via lightning strikes/extreme heat however most deforestation now occurs deliberately due to human action/indirectly via acid rain for example

101
Q

How does deforestation affect biodiversity?

A

Reduces number of trees directly
Species diversity is reduced if only a particular species of tree is felled ; rosewood is often extracted from rainforests and the less usable trees left intact
Reduces number of animal species as it destroys habitats/food source/home - causing a chain effect
Animals are forced to migrate to ensure their survival - may increase biodiversity in other areas

102
Q

Why does replacing areas of trees not help?

A

It restores biodiversity - generally on,y a few commercially viable tree species are planted

103
Q

How does selection reduce biodiversity?

A

Only select species with the best characteristics to give a high yield - only rear a few species/grow a few different species of crop etc

104
Q

What needs to be done in order for it to be economically viable?

A

Many techniques are applied to maximise food production but this again often leads to a reduction in biodiversity

105
Q

Effect of removing hedge grows?

A

They remove them to enable them to use large machinery to help plant fertile crops and frees up extra space - this reduces the number of plant species present in an area and destroys the habitat of animals such as blackbirds, hedgehog and mice
Can lead to soil erosion

106
Q

Use of chemicals like pesticides?

A

Used to kill animals that would eat crops - reduces species diversity directly as it destroys the pest species and indirectly as it destroys the food source of many other animals - food web collapses

107
Q

Herbicides?

A

Used to kill weeds which compete with cultivated plants for water, light, minerals etc and plant diversity is reduced directly - animal diversity may also be reduced by food source removal

108
Q

Monoculture

A

Only one species of plant is present - only a few animal species will be supported by this thus there are low biodiversity levels. The growth of vast oil palm plantations is one of the leading causes of rainforest deforestation leading to a loss of habitat for critically endangered species like the rhino

109
Q

Climate change leads to

A

Global warming - more co2 - more thermal energy trapped atmosphere so our actions are directly linked to global warming

110
Q

4 effects of global warming

A

Extinction of species living in polar ice caps if they melt - habitat shrinks resulting in further migration north in the Arctic
Rising sea levels and thermal expansion of oceans could flood low lying land reducing the available terrestrial habitats - saltwater would flow further up rivers reducing the habitat of freshwater species
High temperatures and less rainfall means many plant species will not survive meaning xerophytes will be dominant - loss of non drought-resistant species of plants leads to loss of animal species dependent on them as a food source
Insect life cycles and populations will change as they adapt to climate change - insects are key pollinators of many plants so if the range of an insect changes, it could affect the lives of the plants it leaves behind, causing extinction + if tropical insects spread they can spread tropical diseases to the poles

111
Q

If climate change is slow?

A

Species may have time to adapt (migrate to a new area for example) - loss of native species but biodiversity will still be the same ; species mix would simply be different

112
Q

3 reasons for maintaining biodiversity

A

Aesthetic, economic and ecological

113
Q

Aesthetic reasons

A
  • Presence of different species enriches our lives allowing us to relax
  • Natural world provides inspiration for people such as musicians and writers who in turn provide pleasure for others through music and books
  • Patients recover more rapidly from stress/injury when they are supported by plants and a relatively natural environment
114
Q

Downside of soil erosion - economic

A

Soil erosion and desertification can occur as a result of deforestation - these can reduce a country’s ability to grow crops and feed its people which can lead to resource/economic dependence on other nations

115
Q

Economic reason for conserving all organisms?

A

Must conserve all organisms that we use to make things as non-sustainable removal of resources such as timber will eventually lead to the collapse of that industry as it will not be economically viable if all the raw material is lost

116
Q

What’s wrong with sustainable methods?

A

New areas will not be as biodiversity as the established habitats they replace (replanting forest areas for example)

117
Q

Economic effect of large scale habitat loss?

A

Species with potentially significant economic impact/medicinal use may become extinct before they are even discovered - many use their own chemical mechanisms

118
Q

Economic effect of monoculture

A

Results in soil depletion - a reduction in the diversity of soil nutrients because the crop takes the same nutrients out of the soil year after year and is then harvested and the nutrients are not recycled. Making the ecosystem more fragile - the crops it can support will be weaker and more vulnerable to opportunistic insects/microorganisms meaning farmers will rely more on expensive herbicides/pesticides

119
Q

What does high biodiversity/genetic diversity protect against (economic reasons)

A

Abiotic stressed and disease - when biodiversity is not maintained a change in conditions can destroy entire crops ; Irish potato famine was a direct consequence of the reliance on only 2 varieties of potato - if the crops do not contain alleles for genetic resistance, the entire crop is destroyed which had economic downsides

120
Q

Areas rich in biodiversity?

A

Provide a pleasing, attractive environment to promote tourism - economic advantages
Greater the potential for the manufacture of different products in the future - these may be beneficial to humans and more financially viable

121
Q

Importance of cross breeding?

A

Can lead to better characteristics such as disease resistance or increased yield - wild relatives of cultivated crop plants provide a genetic reservoir of genetic material to aid the production of new varieties of crops - scientists aim to use genes from wild plants and animals to make crop plants and animals efficient (through genetic engineering) - thus reducing the land required to feed people. If these wild varieties are lost, the crop plants may themselves also become more vulnerable to extinction

122
Q

Main ecological reason

A

All organisms are interdependent and the removal of one species may have a significant effect on others

123
Q

What are keystone species?

A

Species that play a key role in maintaining the structure of an ecological community - they have a disproportionately large effect on their environment relative to their abundance ; they affect many other organisms and determine species richness and species evenness in the community - habitat drastically changes if keystone species is removed ; some may disappear altogether and many species are affected

124
Q

Is it all bad?

A

Humans also play a big part and without human intervention in many places (like with heather burning), one species would dominate - farming, grazing etc all make sure the whole food web/ecosystem is satisfied

125
Q

What is conservation?

A

The preservation and careful management of the environment and of natural resources - by conserving the natural habitat, an organims’ chances of survival are maintained, allowing them to reproduce ; thus species and genetic diversity can be safeguarded

126
Q

In situ conservation

A

Within the natural habitat

127
Q

Ex situ conservation

A

Out of the natural habitat

128
Q

How are species classified?

A

According to their abundance in the wild
1) Extinct - no organisms of the species exist anywhere in the world
2) Extinct in the wild - organisms of the species only exist in captivity
3) Endangered - species that is in danger of extinction
4) Vulnerable - species that is considered likely to become endangered in the near future
FOCUS ON SPECIES THAT ARE CLASSIFIED AS ENDANGERED

129
Q

What is sustainable development?

A

Economic development that meets the needs of people today without limiting the ability of future generations to meet their needs

130
Q

In situ conservation?

A

Takes place inside an organism’s natural habitat
Maintains the genetic diversity of the species and thus evolutionary adaptations that enable a species to adapt continually to factors such as the climate
Preserves the interdependent relationships present in a habitat by allowing them to interact with other species

131
Q

In situ conservation plus

A

Cheaper than ex situ conservation

132
Q

In-situ conservation examples

A

Marine (saltwater), aquatic (freshwater) and terrestrial nature reserves

133
Q

Active managements in a wildlife reserve

A

Controlled grazing - only allowing livestock to graze a particular area of land for a period of time to allow plant species to recover/keep a controlled number of animals in a habitat
Restricting human access - or provide clear paths which must be followed to prevent plants being trampled on
Controlling poaching - create defences to prevent access/issuing fines/removal of rhino horns
Feeding animals - this technique can help to ensure more organisms survive to reproductive age
Reintroduction of species - adding species to areas that have become locally extinct or whose numbers have decreased significantly
Culling invasive species - an organism not native to an area and has negative effects on the economy/environment or health ; these compete with native species for resources
Halting succession

134
Q

What is halting succession?

A

Succession is a natural process in which early colonising species are replaced over time until a stable mature population is achieved - for example, any land left alone will develop into woodland and the only way to protect this is through controlled grazing ; livestock eat seedlings as they appear, preventing succession from heathland to woodland. This is an important role played by humans in maintaining some of our most aesthetically pleasing habitats

135
Q

Marine conservation zones

A

Less we’ll established than terrestrial ones - vital in preserving species-rich areas such as coral reefs which are being devastated by non-sustainable fishing methods ; this creates areas of refuge within which populations can build up and repopulate adjacent areas. LARGE AREAS OF SEA ARE REQUIRED AS TARGET SPECIES OFTEN MOVE LARGE DISTANCES or breed in geographically different areas

136
Q

Ex situ conservation

A

Removal of organisms from their natural habitat - normally done along with in situ to ensure survival of the species

137
Q

Botanic gardens

A

Plant species grown in botanic gardens - here they are provided with best resources/water/provision of soil nutrients and the removal of pests
Roughly more than 10% of world’s flora (in terms of species) are held in botanical gardens but many are not conserved and many wild relatives of selectively bred crops are under-represented but they are potential bank of genes conferring resistance to diseases/pest

138
Q

What is a seed bank?

A

A gene bank - seeds are carefully stored so that new plants may be grown in the future ; dried and stored at cold temperatures to slow down the rate at which they germinate (-20). They will be viable for centuries and provide a back up against extinction of wild plants

139
Q

Downside of seed banks?

A

Doesn’t work for all plants as some seeds due when dried and frozen - many seeds of most tropical rainforests fall into this category

140
Q

Captive breeding programmes?

A

Produce offspring of species in a human-controlled environment - managed by zoos - aim to create a stable, healthy population of a species and then gradually reintroduce the species back into its natural habitat

141
Q

Why does captive breeding focus on vertebrates?

A

There are far more invertebrates facing extinction but humans find it easier to have sympathy with vertebrates so this generates more financial support for their conservation + extends public education

142
Q

Captive breeding programmes include?

A

Prove animals with shelter, nutritious food, absence of predators and medical treatment ; suitable breeding partners can be imported from other zoos if not available

143
Q

Effect of captive breeding on genetic diversity?

A

As only a small number of breeding partners are available - problems related to inbreeding can occur and to overcome this an international catalogue is maintained to ensure that genetic diversity is maximised via mating (genealogical data) - artificial insemination, embryo transfer, long-term cryogenic storage of embryos allow new genetic lines to be introduced without having to transport the animals and without their cooperation

144
Q

Why may some organisms born in captivity not be suitable for release in the wild?

A

Diseases - loss of resistance to local diseases in captive-bred populations : new diseases may develop in the wild to which captive animals have not yet developed resistance
Behaviour - some is innate but a lot has to be learned through copying ; no concept of searching for food for example… so now food is hidden in captivity so they can search for it
Genetic races - genome of captive animals can become so different from the wild that they can’t interbreed
Habitat - natural habitat must be restored if it is very small so more can be added… else introduction of new individuals may lead to stress/tension as individuals fight for limited territory and resources such as food

145
Q

Purpose of conservation agreements?

A

On a local and international scale - cooperation is required to ensure habitats and individual species are preserved ; E.g cross border protections should be offered as animals do not respect a country’s boundaries

146
Q

IUCN

A

Assists in securing agreements between nations - at least once a year they publish the Red list, detailing the current conservation status of threatened animals ; countries then work together to conserve these species

147
Q

CITES?

A

Convention on International Trade in Endangered Species
Regulates international trade of wild plant and animal specimens and their products - requires international cooperation to safeguard certain species from over-exploitation and today more than 35000 species of plants and animals are protected by this treaty

148
Q

Rio Convention

A

1992, 172 nations attended in Rio - become known as the Earth summit

149
Q

Outcomes of the Rio Convention

A

1) Convention on biological diversity requires countries to develop national strategies for sustainable development thus ensuring the maintenance of biodiversity
2) United Nations Framework Convention on Climate Change is an agreement between nations to take steps to stabilise greenhouse gas concentrations within the atmosphere
3) United Nations Convention to combat desertification aims to prevent the transformation of fertile land into desert and reduce effects of drought through international cooperation
ALL INTRINSICALLY LINKED

150
Q

Local conservation schemes?

A

Countryside stewardship scheme - offered government payments to farmers and other land managers to enhance and conserve the English landscape ; aim was to make conservation a part of normal farming and land management practice

151
Q

Specific aims of countryside stewardship scheme

A

Sustaining beauty and diverts of landscape
Improving wildlife habitats
Improving opportunities for countryside enjoyment
Restoring neglected land and conserving archaeological/historical features
NOW REPLACED BY THE ENVIRONMENTAL STEWARDSHIP SCHEME WHICH OPERATES SUCCESFULLY

A-Level Biology (37 decks)

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