Biodiversity Flashcards
1
Q
Biodiversity
A
A measure of the variation found in the living world
2
Q
Habitat
A
Where an organism lives
3
Q
Habitat biodiversity
A
The range of habitats in which different species live i.e. woodlands, parks
4
Q
Species
A
A group of organisms that can freely interbreed to produce fertile offspring
5
Q
Genetic variation
A
Variation between individuals that belong to the same species i.e. different breeds of dogs
6
Q
Why do you need to use samples to measure a habitat
A
-impossible to count all the species present
7
Q
What is a sample
A
A selected small portion of the habitat
-multiply the number of each species found in order to estimate the whole habitat
-Important to take samples that are representative of the whole habitat
8
Q
What are the different sampling types
A
-Random
-Opportunistic
-Stratified
-Systematic
9
Q
Random sampling
A
Sample sites randomly selected
-Use randomly generated coordinates to where you get your samples
-Selecting coordinates from a map and using a portable global-positioning satellite system to find the exact position within the habitat
10
Q
Advantages of Random sampling
A
Ensures that the data is not biased
11
Q
Disadvantages of Random sampling
A
-May not cover all areas of the habitat equally
-Species with a low presence may be missed leading to an underestimate of biodiveristy
12
Q
Opportunistic sampling
A
The researcher makes sampling decisions based on prior knowledge/ during the process of collecting data
Researcher may deliberately sample an area that he/she knows contains a particular species
13
Q
Advantages of opportunistic sampling
A
Easier and quicker then random sampling
14
Q
Disadvantages of opportunistic sampling
A
Data may be biased
-The presence of large/ colourful species may entice the researcher to include that species
-May lead to an overestimate of its importance ad therefore an overestimate in biodiversity
15
Q
Systematic sampling
A
When samples are taken at fixed intervals across the habitat
-Line transects and belt transects
16
Q
Advantages of systematic sampling
A
Useful when the habitat shows a clear gradient in some environmental factor such as getting drier further from a pond
17
Q
Disadvantages of Systematic sampling
A
Only species on the line/ within the belt can be recorded other species may be missed
-Over estimate in biodiversity
18
Q
Preparation when sampling a habitat
A
-Suitable clothing
-Footwear
-Apparatus for sampling
-Clipboard, pen and paper for observations
-Appropriate keys to identify plants
-Camera/smartphone to record specimens and grid location
19
Q
How are plants identified
A
Using a dichotomous key
20
Q
Sampling plants
A
Large plants can be identified and counted individually
Many small plants - calculate a value of % ground cover by each species
21
Q
Quadrat
A
A square frame is used to define the size of the sample area
-Identify plants then measure % cover
22
Q
How can you measure the % cover of a species
A
Using a point frame
- 10 needles, used 10 times = 100 readings
- Each plant that touches = 1% cover
-Also make sure to account for bare ground
23
Q
Transect
A
line taken across the habitat
-Samples taken along the line
24
Q
Interrupted belt transect
A
Using a quadrat at set intervals along the transect
-Provides quantitive data at intervals across the habitat
25
Why is gaining quantitative data for animals difficult
-Not easy to spot
-Hide away
-Move too quickly for accurate counting
26
How can you estimate the population size of large animals
Looking for signs that they have left i.e. footprints/ droppings
-Owls deposit pellets of undigested food, rabbits have burrows, and deer damage the bark of trees in particular ways
-DNA sequencing to distinguish DNA droppings from different individals
27
Different methods of catching invertebrates
-Sweep net
-Pooter
-Hitting a branch against a branch after laying down a white sheet to dislodge any small animals
-Pitfall trap
-Tullgren funnel
-Light trap
28
Sweep net
1) Walk through the habitat with a stout net
2) Sweep the net through the vegetation in wide arcs
3) Small insects get caught in the net
4) Empty contents onto a white sheet to identify
-useful for low vegetayion that is not to woody
29
Pooter
Collect animals before fly away
30
Collecting from trees
Hitting a branch against a branch after laying down a white sheet to dislodge any small animals by the vibrations
-Quick to identify before fly away
31
Pitfall trap
Trap set in the soil to catch small animals
-Small container buried in the soil so the rim is just below the surface
-Animals moving through plants/leaf litter on the soil surface will fall into the container
-Trap should contain some water/scrunched-up paper to stop animals from crawling out
-Rainy weather plants should be sheltered from the rain so does not fill up
32
Tullgren funnel
Device for collecting small animals from leaf litter
-Place leaf litter in funnel
-Light above the litter drives the animal downwards as the litter dries and warms up
-Fall through a mesh screen to be collected into a jar underneath
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Light trap
Collects flying insects at night
-Ultraviolet light that attracts the insects
-under light is a collecting vessel containing alcohol
-Moths/other insects attracted to light fall into alcohol
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How are small animals trapped
Long worth trap
- Must be monitored regularly to release any trapped animals
- Population size - mark-recapture technique
35
Mark recapture
1) Capture a sample of animals
2) Mark individuals with non-toxic paint ( C1)
3) Release marked individuals and leave the traps for a period of time
4) Number captured on second occasion (C2) ones that are already marked (C3)
36
Mark - recapture formula
(C1 X C2) / C3
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Disadvantages of longworth traps
Estimate calculated affected by animals that learn trap harmless and contains food
-Animals do not like experience so keep away
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How are populations of birds est.
Ringing technique
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Species richness
A measure of how many different species are present
40
Species evenness
A measure of how evenly represented the species are
41
How can species richness/evenness be measured?
Richness - counting
Evenness - quantitative survey
42
Way to measure species evenness
Plants - % cover
Large animals - counting
Small animals - mark-recapture
Water - use a net to sift through mud at bottom
43
Simpsons Index of Biodiversity
A measure of the diversity of a habitat
D = 1-( E (N/n) 2)
N = Total number of all the individual species
n = number of individuals
44
What does a high Simpsons Index of Biodiversity suggest
Diverse habitat
-small change may affect one species but if species only a small part of the habitat is affected
- Stable / Able to withstand change
45
What does a low Simpsons Index of Biodiversity suggest
Habitat is dominated by a few species
- Small change that affects one species could damage/destroy the whole habitat
i.e. predator/ disease/ human activity
46
Why is measuring genetic diversity important
Can help to assess the value of that population as a resource for conservation
-Can be done by a simple assessment of looking at the observable features of the individual
47
Define: Allele/ gene variant, locus
- A version of a gene
- The position of a gene on a chromosome
48
Where is genetic diversity found
Where there is more than one allele for a particular locus
- More differences between gametes produced by members of the population
49
How to calculate genetic diversity - 2 methods
1) estimating the number of loci in one individual that is heterozygous (containing two different alleles)
-Does not give a good measure of the population as a genetic resource
2) calculating the % of loci in the population that has more than one allele (us equation)
50
The equation to calculate genetic diversity
(number of species in the population with loci with more than one allele/number of loci in species) x 100%
51
Polymorphic gene loci and advantages
A locus that has more than two alleles
-Increases genetic diversity
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e.g. of polymorphic gene loci
ABO blood group in humans
-the individual has one locus for this gene at each pair of alleles
- Can have two copies of gene which can be the same or different i.e. AA/AB
- Increases genetic diversity
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The proportion of polymorphic gene loci equation
Number of polymorphic gene loci/ total number of loci
54
How has human population growth affected biodiversity
Need more food
-Alter ecosystems to provide this
-Destroy and fragment habitats
-Use Earths resources
-Pollute the atmosphere
55
how has agriculture affected biodiversity
Clearing vegetation reduces the size of habitats - reduces genetic diversity
- Species have less capacity to adapt to changing conditions through evolution
-Leads to isolated and fragmented populations too small to survive
56
Modern agriculture
Relies upon monoculture and selective breeding
- Rainforest cut down and replaced with one strain of species i.e. palm oil
- SB - ignores other charcteristics so gd declines
57
Genetic erosion
Where an already limited gene pool of an endangered species diminishes more when individuals from surviving population die off without breeding
58
How has Climate change affected biodiversity
Species that have lost genetic diversity are less able to adapt to changing climate
When trying to migrate to other areas they are obstructed by:
- Major human developments
-Agricultural land
-Large bodies of water
-Mountain ranges
In national parks will start to migrate to areas that are not protected
59
Climate change's effect on agriculture
Monocultures/ Selective breeding - little genetic diversity
-Cannot adapt and is vulnerable to disease
60
Extinction
When the last living members of a species dies and the species ceases to exist
61
Current facts about extinction
- 800 recorded extinctions since 1500
-20% of species today extinct by 2030
- Current rate of extinction is faster than any other extinction event
Caused mainly by human activity
62
Keystone species
One that has a disproportionate effect upon its environment relative to its abundance
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E.g of an animal keystone species
Maybe predators that limit the pop of herbivores so veg not over-grazed
-Mountain lions in Kaibab Plateau in Arizona were hunted to protect the deer pop, deer increases ate all veg then pop plummeted as deer all starved
64
E.g of a plant keystone species
A plant that is dominant in the habitat has an effect on other species
-Sugar maple has deep roots that eaches water overground and provides water for plants with shallow roots
-Foliage keeps conditions moist for earthworms
-Shade prevents excess overgrowth
-Sap - food for insects
-Canopy - home
65
Beaver as a keystone species
Build dams to prevent large areas being flooded and provided water habitats
66
Environment as a genetic resource
Populations of wild plants have had a long time to evolve and adapt to problems presented by the environment/ pests and diseases
-Careful selection and breeding may be able to find new crop varieties that can cope with the new conditions of climate change
-Genetic engineering to produce transgenic species could also be used to good effect
-New medicines/ vaccines
67
How do ecosystems provide processes that are of value to humans
- All impact on food production (Economic reasons to maintain biodiversity)
-regulation of atmosphere and climate
-Purification and retention of fresh water
-Formation and fertilisation of soil
-Recycling nutrients
-Detoxification and recycling of wastes
-Crop pollination
-Growth of timber, food, soil
-Discovery of molecules with the potential of new medicines
68
What is one of the most immediate affects that loss of biodiversity has on food
depletion of soil
- Monoculture - less fertile as the same plant always take the same minerals and when harvested take these from the ecosystem
-Seen in the dust storms
69
Soil depletion
The loss of soil fertility caused by the removal of minerals by continuous cropping
70
Aesthetic reasons to maintain biodiversity
-Well-being and physical health
71
How does the living biosphere affect the habitat (Aesthetic reasons)
Tropical rainforests protect the soil from climatic factors such as rainfall which could cause soil erosion
-Woodlands act as a reservoir when it rains
-Trees take up water and organic matter in the soil and hold it - run off and drainage reduced
-Water collected in forested hills will slowly drain and supply water downstream after rainfall has stopped
72
What happens if biodiversity is reduced and the soil is left exposed (Aesthetic reasons)
-Reducing biodiversity exposes soil and changes the landscape
i.e. deforestation - floods as less soil protection and building of roads means more surface runoff
Rainfall will erode soil (extreme cases) and wash it downstream, deposited where water flow is reduced and further reduces drainage - increasing chances of flooding
-Water no longer stored in hills and when rain stops flood followed by drought
73
Conservation
Active management to maintain habitats and the species that live in those habitats
-the aim is to enable endangered species to survive and maintain biodiversity
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Conservation in situ
Carrying out active management to maintain the biodiversity in the natural environment
75
Different methods of conservation in situ
-Legislation
-Wildlife reserves
-Land management agreements on private land and farm sites
-Repopulation
76
Legislation (conservation in situ)
Pass legislation to stop: Hunting, logging, and clearing land for agriculture
-Specific to each country
-Difficult to persuade some countries
-Difficult to enforce if government not in favour
77
Wildlife reserves (conservation in situ)
Designated areas est. for the conservation of habitats and species
78
Principles for choosing a wildlife reserve
1) Comprehensiveness - How many species are represented / environmental conditions
2) Adequacy - is the area large enough for the long-term survival of species
3) Representaviness - is there a full range of diversity in each species and environmental conditions
79
How should conservation include human activity
Reserve should meet the needs of indigenous people who might use the land for: traditional hunting, religious activities
80
Why are there conflicts if a reserve has been made without consideration for local people
1) Protected animals come ut of the reserve and raid crops
2) People poach protected animals for food
3) Illegal harvesting of timber and other plant products
4) Tourists feeding protected naimals or elaving litter
81
Wildlife reserves in the UK
-National parks
-National Nature Reserves
-Sites of Special Scientific Interest (SSI)
-Local nature reserves - often run by County Wildlife trusts
-Marine Conservation Zones
82
Marine Conservation Zones
Area of sea set aside to conserve the diversity of species and habitats
83
Advantages of in situ conservation
-Plants and animals are conserved in their natural environment
-Permanently protects biodiversity and representative examples of ecosystems
-Protects significant elements of natural and cultural heritage
-Allows management of areas to ensure ecological integrity is maintained
-Provides opportunities for ecologically sustainable land uses, including traditional outdoor heritage activites and associated economic benefits
-Facilitates scientific research
-May be possible to improve and restore the ecological integrity of the area
84
Disadvantages of in situ conservation
-Endangered habitats may be fragmented and each small area may not be large enough to ensure the survival
-Populations may have already lost much of their genetic diversity
-Conditions that cause habitat or species to become endangered may be still present
-Area can act as a 'honeypot' to poachers and eco-tourists, who inadvertently cause disturbance
85
Repopulation
Where biodiversity has been lost it is possible to rebuild by clearing agriculture fro habitat recovery and slowly reintroducing species back into the habitat
86
Conservation ex-situ
Conservation outside the normal habitat of the species
87
e.g. of Conservation ex situ
-Zoos
-Botanic Gardens
-Seed banks
-Storage of seeds
88
Zoos (conservation ex-situ)
-Captive breeding - Breeding endangered species and conducting research that should benefit
-Modern reproductive technologies i.e. freezing eggs and sperm = large amounts of genetic material
-Artificial insemination/ in vitro fertilization/embryo transfer
-Research carried out sometimes on less endangered species that are similar so endangered and spared from experimental research
89
Adnatages of ex situ conservation
-Organisms protected from poaching/predation
-Health monitored and medical assistance can be given
-Populations can be divided so if there is a disaster one population will still survive
-Genetic diversity of the population can be measured
Selective breeding to in genetic diversity
-Modern reproductive tech can increase reproductive success
- Animals/ plants bred to increase the number of species
-Research into reproductive physiology, lifestyle, ecology of endangered species is easier
- Sites can be used to raise funds for other conservation efforts
-Conservation sites can be used for education
90
Disadvantages of ex situ conservation
- Captive population = low genetic diversity
- Animals exposed to a wide range of diseases
-Outside natural habitat
-Nutritional issues may be difficult to manage
-Animals may not behave as normal = reproduction difficult
-Correct environmental conditions for survival = difficult to achieve
-Expensive to mantain suitable environmental conditions
-animals need to survive reintroduction to wild - finding food/ predation
-When reintroduced existing species may not accept presence
91
Advantages of botanic gardens
-As part of the life cycle plants have a dormant stage - seed
-Seeds produced in large numbers collected from the wild without too much disturbance
-Seeds stored and germinated in protected surroundings
-Seeds stored in large numbers without occupying too much space
-Plants bred asexually
-The number of individuals increases quickly through techniques such as tissue culture - ample supply for research/ reintroduction to wild
-Captive-bred individuals replanted in wild
92
Disadvantages of botanic gardens
-Funding
-Collecting wild seeds = disturbance
-Collected - not representative level of genetic diversity
-Seeds stored for any length of time may not be viable
-Plants bred asexually will be genetically identical
-Conclusions on research based on small sample may not be valid for whole species
93
Seed banks
A collection of seed samples
94
Biggest seed bank
The key Millenium Seed bank project
-Store representative samples of seeds of every known species of plant
95
Advantages of seed banks
Contain seeds that remain viable for decades
Stored to provide wide benefits for humanity:
-Providing seeds for food/ building materials for rural communities/ disease-resistant crops for agriculture
-Habitat reclamation and repopulation of endangered habitats
96
How are seeds stored
To prolong viability stored in dry/freezing conditions
-Seeds resistant to desiccation and level of moisture in each seed has a direct effect on storage
-For every 1% decrease in moisture level - life spean doubles
-For every 5 degrees life span doubles
97
What may happen to seeds when they are stored
May deteriorate so have to be tested at regular intervals for viability
-Remove samples and germinate in petri-dish of nutrient agar in controlled conditions
98
CITES
The Convention on International Trade in Endangered species
99
CITES aims
1)Regular and monitor international trade in selected species of plants and animals
2)Ensure international trade does not endanger the survival of populations in the wild
3)Ensure trade in wild plants for commercial purposes is prohibited
4)Ensure trade in artificially propagated plants is allowed, subject to permit
5)Ensure some slightly less endangered species may be traded subject to permit, as agreed between exporting/importing countries
100
Why may international trade policies be hard to enforce
When there is a demand for a product there will always be attempts to supply it
101
Rio Convention on Biological Biodiversity
Aims for sustainable development of people and resources as well as the biological diversity of plants and animals
102
Rio Convention on Biological Biodiversity aims
-Conservation of biological diversity
-Sustainable use of its components
-Appropriate shred use to genetic resources
-Appropriate sharing and transfer of scientific knowledge and technologies
-Fair and equitable sharing of benefits arising out of the use of genetic resources
Encourages cooperation between country and states, national strategy for conservation, ex-situ must complement in situ measures
103
The Countryside Stewardship Scheme
A scheme to encourage farmers and other land owners to manage parts of their land in a way that promotes conservation
104
The Countryside Stewardship Scheme aims
-Improve the natural beauty and diversity of the countryside
-Enhance, restore and re-create targeted landscapes, their wildlife habitats, and historical features
-Improve opportunities for public access
105
Environmental Stewardship scheme aims
(Replaced The Countryside Stewardship Scheme)
Provides funding and advice to land managers to:
-Look after wildlife species and their many habitats
-Ensuring land is well managed and retains its traditional character
-Protecting historic features and natural resources
-Ensuring livestock and crops are conserved
-Providing opportunities for people to visit and learn about the countryside
