CHAPTER 11 - BIODIVERSITY Flashcards
1
Q
What is biodiversity
A
The variety of living organisms present in an area
2
Q
All species are interconnected. What does that mean
A
They depend on one another, and any impact on one could have impacts on another
3
Q
What is an example of interconnectedness of species
A
Trees provide a home for animals
Animals eat plants
Which need fertile soil to grow
Fungi and microorganisms help decompose dead plants and animals, returning nutrients to the soil
4
Q
What type of regions have high biodiversity
A
Tropical moist regions (warm all year round)
5
Q
What type of regions have low biodiversity
A
Either very cold areas (Arctic) or very dry areas (deserts)
6
Q
How does measuring biodiversity play an important role in conservation
A
Informs scientists of the species that are present, thus providing a baseline for the level of biodiversity in an area
The effect of any changes to an environment can then be measured eg. human activity, disease or climate change
7
Q
What does the Environmental impact assessment measure
A
The positive and negative effects of a project on the biodiversity of an area, looking at
Habitat biodiversity
Species Biodiversity
Genetic biodiversity
8
Q
What is habitat biodiversity
A
The number of different habitats found within an area
9
Q
What habitats are in the UK
A
Meadow, woodland, streams and sand dunes - large habitat biodiversity
10
Q
What are the two components to species biodiversity
A
Species Richness and Species Evenness
11
Q
What is species richness
A
The number of different species living in a particular area
12
Q
What is species evenness
A
a comparison of the number of individuals of each species living in a community
13
Q
What is genetic biodiversity
A
The variety of genes that make up a species
14
Q
What can a large genetic biodiversity lead to
A
Very different characteristics being exhibited within a species
Better adaption to a changing environment and more likely to produce individuals who are resistant to disease
15
Q
State the difference between species richness and species evenness
A
Species richness – the number of different species living in a specific area
Species evenness – the number of individuals within the species living in a community
16
Q
Compare the biodiversity of an arid desert and a temperate coastline
A
Habitat biodiversity:
desert – low;
coastline – high (1).
Suitable habitat examples given (1).
Species biodiversity:
desert – low; coastline – high
17
Q
Suggest why greater genetic biodiversity increases a species chances of long-term survival
A
Greater genetic variation / wider range of alleles
therefore increased likelihood some organisms are suited to a habitat change
some organisms may be suited to different habitats
therefore more areas may be colonised by the species
some individuals will be resistant to a new disease
therefore lower probability of all organisms being killed by the disease
some organisms will be better adapted to avoid new or adapted predators / catch prey
therefore less chance of being eaten / starvation
other suitable example with consequence
18
Q
What is sampling
A
Taking measurements of a limited number of individual organisms present in a particular area
19
Q
What can sampling be used to estimate
A
The number of organisms in an area without having to count them all
Measure of a particular characteristic
20
Q
What is the abundance of an organism
A
The number of individuals present in an area
21
Q
What are the two key ways in which sampling can be done
A
Random and non-random
22
Q
What is random sampling
A
Individuals are selected by chance, each individual in the population has an equal likelihood of selection
23
Q
What are the types of non-random sampling
A
Opportunistic, stratified and systematic
24
Q
What is opportunistic sampling
A
Uses organisms that are conveniently available
The weakest form of sampling as it may not be representative of the population
25
What is stratified sampling
Some populations can be divided into a number of strata (sub-groups) based on a characteristic - eg. males and females
A random sample is then taken from each of these Strata proportional to its site
26
What is systematic sampling
Different areas within an overall habitat are identified and sampled separately eg. change in plant species as you move inland from the sea
27
What is systematic sampling carried out using?
A line transect or a belt transect
28
What is a line transect
Marking a line on the ground between two poles and taking samples at specified points, which can include describing all of the organisms which touch the line or distances of samples from the line
29
What is a belt transect
Two parallel lines are marked, samples are taken of the area between the two lines
30
What are the two contentions to reliability
Sampling bias and chance
31
What is sampling bias
Where the selection process may be biased, either accidentally or deliberately.
eg. choosing to sample a particular area that has more flowers because it looks interesting
Can be reduced by removing human involvement in selecting areas to sample
32
What is chance (in reliability of sampling)
Where the organisms selected may, by chance, not be representative of the whole population
eg. a sample of 5 worms maybe the 5 longest worms in the habitat
Chance can never be removed but it can be minimised by using a greater sample size
33
State the difference between random and non-random sampling
Random – all organisms have an equal chance of selection
non-random – different organisms have higher / lower probabilities of being selected
34
Describe how you can increase the likelihood of a sample being a reliable representation of the population as a whole
Use random sampling
removes sampling bias
use as large a sample size as possible
removes the effects of chance
35
State and explain which type of sampling you would use to study
A) how organisms differ throughout the length of a stream
B) Th distribution of organisms on a school field
A) Systematic sampling -
abiotic conditions vary as you travel downstream affecting the type and abundance of organisms present
B) Random sampling
environment easy to study/fairly uniform
reduces sample bias/increases reliability
36
What is a pooter used for
To catch small insects.
Sucking on a mouthpiece insects are drawn into the holding chamber via the inlet tube. A filter before the mouthpiece prevents them from being sucked into the mouth.
37
Are sweep nets used for
To catch insects in areas of long gras
38
What are pitfall traps used for?
To catch small, crawling invertebrates, such as beetles, spiders and slugs.
A hole is dug into the ground which insects fall into. It must be deep enough that they cannot crawl out and covered with a roof structure propped above, so that the trap does not fill with rainwater.
The traps are normally left overnight so that nocturnal species are also sampled.
39
What is tree beating used for
It is used to take samples of the invertebrates, living in a tree or a bush.
A large white cloth is stretched out under the tree. Animals will fall onto the sheets where they can be collected and studied
40
What is kick sampling use for?
To study the organisms, living in a river.
The riverbank and bed is kicked for a period of time to disturb the substrate.
A net is held just downstream for a set period of time in order to capture any organisms released into the flowing water.
41
What are the two main types of quadrat
Point Quadrat and
frame quadrat (Stonehouse special)
(pg 275)
42
What can be measured using frame quadrats
Population
Density
Frequency
Percentage cover
43
How would you estimate an animal population
Capture-mark-release-recapture method
44
Why is using sensors to measure abiotic factors advantageous
Rapid changes can be detected
Human error in taking a reading is reduced
high degree of precision
data can be stored and tracked
45
State which piece of equipment you would use to collect sample data on the number of beetles on an oak tree trunk
Pooter
46
State which piece of equipment you would use to collect sample data on the number of moths in an area of woodland
Sweep net
47
State which piece of equipment you would use to collect sample data on the pH of soil along a line transect
pH probe
48
State which piece of equipment you would use to collect sample data on the number of plant species on a school playing field
Quadrat
49
Describe the advantages of using a temperature probe over a thermometer
likely to have higher resolution;
rapid changes can be monitored;
less possibility for human error;
data can be stored on a computer
50
Discuss the advantages and disadvantages of the different ways to measure species evenness
Population density – advantages:
accurate;
disadvantages:
time consuming, can only be used when individual members of a species can be identified
Frequency –
advantages:
rapid, can be used when individual members of a species cannot be identified;
disadvantages:
only gives an approximate result
Percentage cover – advantages: allows a lot of data to be collected quickly; disadvantages: only gives an approximate result; least precise sampling technique
51
What Is the formula used to measure biodiversity
Simpsons index of diversity (D)
D = 1 - Sum of (n/N)^2
52
What are some features of an area with low biodiversity
Few successful species
Stressful environment with few ecological niches
Very adapted to live in environment
Simple food webs
change to environment would have major impacts on ecosystem
53
What are some features of an area with high biodiversity
Many successful species
Unstressful environment with many ecological niches
Not many adapted to live in environment - many species live there
complex food webs
change to environment would have minor impacts on ecosystem
54
What is an advantage of a species having a wide genetic diversity
More likely to adapt to changes in their environment
55
What are the factors that will increase genetic biodiversity
Mutation - creating new allele
Interbreeding - when an individual from one population breeds with the member of another, alleles are transferred between the two populations - gene flow
56
What are the factors that will decrease genetic biodiversity
Selective breeding
Captive breeding
programmes
Rare breeding
Artificial cloning
Natural selection
Genetic bottleneck - few individuals surviving an event or change
Founder effect - small number of individuals create a new geographically isolated colony with a small gene pool
Genetic drift - the frequency of the allele being passed down generations and eventually disappearing all together
57
Describe how genetic biodiversity in a population can increase
number of alleles in a population must increase
mutations can create new alleles
gene flow can introduce new alleles into population
58
Explain why it is advantageous for a species to be genetically biodiverse
More genetically biodiverse a species is the greater variation in DNA/number of alleles present
species more likely to survive a change to the environment
as there is a higher probability that some members of the species will have the allele to survive the change and reproduce
59
What are the human influences on biodiversity
Deforestation
Agriculture
Climate change
60
How does deforestation affect biodiversity?
It directly reduces the number of trees present in an area
It's only a specific type of tree is felled the species diversity is reduced
It reduces the number of animal species present in an area as it destroys the habitat and their food source
Animals may be forced to migrate to other areas to ensure that survival
61
How does agriculture affect biodiversity?
Deforestation to increase the land available for growing crops or rearing animals
Removal of hedgerows, resulting to extra land and to allow large machinery to farm
Use of chemicals such as pesticides and herbicides
Herbicides are used to kill weeds, reducing biodiversity
Monoculture, which greatly lowers the biodiversity as well as making the population susceptible to disease
62
How does climate change affect biodiversity?
Melting of polar ice caps could lead to the extinction of the few plants and animal species living in these regions
Rising sea levels could flood, low-lying land and terrestrial habitats
Higher temperatures and less rainfall would result in some plant species failing to survive, leading to drought resistant species becoming more dominant
Insects life-cycle is the population will change as they adapt to climate change
63
And explain how the following factors reduce species diversity:
Monoculture
Building of roads
Use of pesticides
Monoculture:
Only one type of plant is grown
This will be the food source for only one / a few species of animal
Building of roads:
Deforestation / removal of habitat / reduction in plant diversity
leading to reduction in animal diversity because more limited range of foods / shelter available
Use of pesticides:
Pesticides remove pest species
which reduces the food source for the animals that live off these species
64
Explain why there is a reduction in species diversity when an area of forest is cleared to create additional land for the grazing of castle
Deforestation removes the food source for a / many species, which causes starvation for the predator species which feed on them
loss of habitat removes the shelter used by organisms, causing local extinction / migration
migration of species can lead to reduction in species diversity in adjacent areas
65
Suggest and explain ways in which climate change can affect biodiversity in an area
Polar ice caps melting / reducing in size leads to reduction in size of ice sheets, removing the habitat of the native species
rising sea levels leads to loss of habitats in low lying land / salination of rivers further upstream, affecting the species which inhabit these areas
higher temperatures can lead to drought in a region, affecting non-drought resistant species
insect life cycles and populations may change, spreading diseases to new regions, affecting the animal organisms which live in these areas
66
What are some aesthetic reasons for maintaining biodiversity
The presence of plants and animals in ur environment enriches our lives
Natural world provides inspiration for people such as musicians and writers
Studies have shown that patients recover more rapidly from stress injury when they are supported by plants in a relatively natural environment
67
What are some economic reasons
Soil, erosion and desertification results and deforestation reducing in countries ability to grow crops and feed its people
Conserving all organisms that we use to make things such as hardwood timber
Large-scale habitats and biodiversity loss means that species with potential economic or medical importance may become extinct before they are discovered
continuous monoculture results in soil depletion
High biodiversity provides protection against abiotic stress
Areas rich in biodiversity Provide a pleasing attractive environment for tourism.
68
What are some ecological reasons for maintaining biodiversity
All organisms are interdependent on others for their survival, so the removal of one species may have a significant impact on the entire food chain
Species play a key role in maintaining the structure of ecological community, e.g. keystone species who have a disproportionately large effect on their environment
69
State the differences between aesthetic economic and ecological arguments for maintaining biodiversity
Aesthetic – how the region appears;
economic – how the region can provide an income;
ecological – the species that can be supported in the region
70
Suggest two ethical reasons why we should maintain biodiversity
All living organisms have right to survive and live in the way they have become adapted
habitat and biodiversity loss prevents many organisms living where they should
moral responsibility to conserve for future generation
71
Irish potato famine of the 1840s, had a devastating effect on the population.
A) Explain how a lack of agricultural biodiversity led to this disaster and
B) suggest and explain how similar famine could be prevented from occurring in the future.
A) Only two potato varieties plants in Ireland so little genetic diversity
when new disease introduced (Phytophthora infestans) no potato had resistance to disease
B) Plant wider range of crops to increase genetic biodiversity within populations
if new disease/climate change/pests introduced some will have resistance/ ability to tolerate changing conditions, so some crops will survive
72
What is in situ conservation
Conservation within the natural habitat
73
What is ex situ conservation
Conservation out of the natural habitat
74
What is the species classification in the wild
Extinct - no organisms of the species exists anywhere in the world
Extinct in the wild - organisms of the species only exist in captivity
Endangered - a species that is in danger of extinction
Vulnerable - a species that is considered likely to become extinct in the future
75
As a method of in-situ conservation, how do wildlife reserves protect their animals
Controlled grazing
Restricting human access
Controlling poaching
Feeding animals
Reintroduction of species
Culling or removal of invasive species
Halting succession
76
What are some examples of ex situ conservation
Botanic gardens
Seed banks
Captive breeding programs
77
What are some reasons why organisms bred in captivity may not be suitable for release into the wild
Disease - loss of resistance
Behaviour - lost hunting instincts from just being given food
Genetic races - too different from original population they cannot interbreed
Habitat - too different
78
What are some conservation agreements
International union for the conservation of nature
Rio convention of 1992
Countryside stewardship scheme
79
Describe three methods of ex situ conservation
Captive breeding – animals reared and bred in human-controlled environments
Seed banks – collections of seeds are stored (at low temperatures) for future use
Botanic gardens – collections of plants are grown in controlled environment
80
Discuss the advantages and disadvantages of captive breeding programmes
Advantages –
allows for an individual of a species to survive; maintains or increases endangered populations
allows for reintegration of a species into its natural habitat
Disadvantages –
leads to loss of genetic diversity
leads to organisms not learning behaviours of their wild counterparts
can decrease the disease resistance of a population genetic problems can occur in offspring due to in-breeding
81
State and explain four techniques used in the active management of wildlife reserves
Controlled grazing allows species time to recover, rather removing them entirely from habitat
restricting human access to prevent poaching / avoid plant species being trampled
feeding animals to ensure native populations able to survive to reproductive age
culling/removal of invasive species to ensure native species able to access resources / to remove competition for resources
halting succession ensuring the habitat remains in its current state, so appropriate resources are available for current species
82
Explain why local and international agreements can help to preserve biodiversity
Landowners/countries have economic/cultural reasons for exploiting natural resources
exploitation leads to loss of biodiversity
(financial) incentives often needed to replace income exploiting a resource would provide; animals do not respect nation’s boundaries
agreements between nations needed to manage endangered populations and help limit trade of controlled/protected species
to preserve number of species in natural habitat
