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How the effects of the following on enzyme activity be investigated
experimentally
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pH
A starch-agar plate is made up by mixing starch with agar.
The mixture is poured into a petri dish and left to set. It forms a semi-rigid gel in the plate.
Cut wells into each plate using a cork borer
Into each well place the same volume of a different pH buffer solution
Into each well except one, place an identical volume of amylase solution
Into the well without the amylase, add an equal volume of distilled water as a control
Incubate for 24h in a dry oven at 35˚C
Flood the plate with an iodine solution and rinse with water
Measure the diameter of the cleared zone- this gives an indication of how much substrate
has been turned into product
temperature,
Take samples of potato tissue (containing catalase) using a cork borer then stick into discs
of equal thickness
Place an equal number of discs in each of seven test tubes and place one in each of a range of
water baths from 20-80˚C
Place an equal volume of pH 7 buffer and hydrogen peroxide into each of seven separate test tubes and place one
in each water bath.
Allow to equilibrate.
Taking each in turn, add peroxide/buffer mixture to the potato discs, then fix a stopper and a side arm into the
tube.
Close the clip.
As oxygen gas is produced in the reaction it pushes the water bubble along the side arm.
Time how long it takes for the bubble to move 5cm.
enzyme concentration
Use the reaction as before, but keeping the temperature constant, and instead having a
different number of potato discs in each test tube
substrate concentration
As before, but keeping the temperature and the number of potato discs the same and changing the concentration
of hydrogen peroxide in each test tube
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Cofactors
Ions (eg Cl-) that increase the rate of enzyme-controlled reactions. They bind to the
enzyme and allows enzyme substrate complexes to form more easily.
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Coenzymes
Small, organic, non-protein molecules that bind for a short period of time to the
active site.
They may bind just before, or at the same time, as the substrate binds. In many
reactions,
coenzymes take part in the reaction, and like substrate, are changed in some way.
Unlike
the substrate, coenzymes are recycled back to take part in the reaction again. The
role of
coenzymes is often to carry chemical groups between enzymes so they link together
enzyme-controlled reactions that need to take place in sequence.
Some coenzymes are permanent parts of the enzymes- prosthetic groups. These
contribute
to the shape of the enzyme.
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Research and read around the
following topics
• (1) define the terms: Species, Habitat and
Biodiversity
• (2) explain how biodiversity may be
considered at different levels; Habitat,
Species, and genetic
• (3) explain the importance of sampling in
measuring the biodiversity of a habitat;
• (4) describe how random samples can be
taken when measuring biodiversity
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Research and read around the
following topics
• (1) define the terms: Species, Habitat and
Biodiversity
• (2) explain how biodiversity may be
considered at different levels; Habitat,
Species, and genetic
• (3) explain the importance of sampling in
measuring the biodiversity of a habitat;
• (4) describe how random samples can be
taken when measuring biodiversity
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AS OCR Biology
Unit F212
Module 3
2.3.1 Biodiversity
2.3.4 Maintaining Biodiversity
2.3.1 Biodiversity
Objectives
Definitions – species, habitat, and biodiversity
Levels of biodiversity – habitat, species, and
genetic
Measurement of biodiversity by sampling; taking
of random samples
Measurement of species richness and species
evenness in a habitat
Simpson’s Index of Biodiversity (D) –
calculation of biodiversity using the formula;
significance of high and low values of D
Current estimates of global biodiversity
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Definitions
Group of similar organisms (i.e. with similar morphology) which are capable of
interbreeding (mating) to produce fertile offspring (i.e. offspring that can
breed to give rise to more offspring) and are reproductively isolated from other
species
The environment in which a particular organism (species) lives – e.g
earthworm - soil; fish -pond. Organisms from a single species may live in a
number of different habitats
Organisms are adapted to their habitat. It includes the abiotic (physical) factors
(e.g. soil, temperature, water) and biotic (living) factors (e.g. availability of food,
presence of other organisms; predators)
The variety of life forms (the different species of organisms) within a given
ecosystem, biome, or the world. An area with many different species has a
higher biodiversity than one with few species. Identified traditionally at three
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levels habitat, species, and genetic
Definitions
Species
Group of similar organisms (i.e. with similar morphology) which are capable of
interbreeding (mating) to produce fertile offspring (i.e. offspring that can
breed to give rise to more offspring) and are reproductively isolated from other
species
Habitat
The environment in which a particular organism (species) lives – e.g
earthworm - soil; fish -pond. Organisms from a single species may live in a
number of different habitats
Organisms are adapted to their habitat. It includes the abiotic (physical) factors
(e.g. soil, temperature, water) and biotic (living) factors (e.g. availability of food,
presence of other organisms; predators)
Biodiversity (biological variety)
The varietyof life forms (the different species of organisms) within a given
ecosystem, biome, or the world. An area with many different species has a
higher biodiversity than one with few species. Identified traditionally at three
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levels habitat, species, and genetic
Habitat Diversity - i.e. the range of habitats in which different species live
Species Diversity - i.e. the number of different species and the abundance
of each species in an ecosystem. Differences in species (e.g. structural (tree
and an ant; functional – bacteria that cause decay and those that digest food))
Genetic Diversity - i.e. the variation of alleles within a species (or a
population of species).
Genetic variation between individuals belonging to the same species
A number of genes are the same in different species – similar fundamental
biochemistry and cell structures – e.g. respiration – requires same enzymes
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Species Richness and Species Evenness
The biodiversity in a particular area is influenced by two factors
– species richness
i.e. the number of species found in a habitat
- species evenness.
i.e. the relative numbers or abundance of individuals in each
species
Species Richness (number of different species in an area)
Number of different species per sample (in an area) is a measure of richness - the
more species present in a sample, the greater the species richness.
Measured by taking random samples of a habitat and counting the number of
different species
Species richness on its own takes no account of the number of individuals of each
species present. - it gives as much weight to those species which have very few
individuals as to those which have many individuals.
Thus, one daisy has as much influence on the richness of an area as 1000 buttercups.
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Species Evenness (relative abundance of each species in an area)
Evenness is a measure of the relative abundance of each species in an area. The
more similar the population size of each species, the greater the species evenness. It
is measured by taking random samples of a habitat, and counting the number of
individuals of each different species.
Abundance in plants can be measured as percentage cover
The greater the species richness and species evenness in an area,
the higher the biodiversity
The diversity of species in a habitat is an indicator of environmental
conditions and conservation status
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Example illustrating richness and evenness
Sample sites - two different fields
(habitats) of wildflowers
Field 1
Field 2
Daisies
300
20
Dandelions
335
49
Buttercups
365
931
TOTAL
1000
1000
•In the second sample, most of the
individuals are buttercups, with only a few
daisies and dandelions present.
•Sample 2 is therefore considered to be
less diverse than sample 1.
Species evenness is a measure of the
relative abundance of each species in a
habitat and counting
Measured by taking random samples of
the habitat and counting the numbers of
each individual species
In field 1 the individual organisms are
more evenly distributed between the
three different species – it has greater
species evenness
Species richness is the number of
different species in a habitat. The higher
the number of species the greater the
species richness
Measured by taking random samples of a
habitat and counting the number of
different species
Both sampling sites(fields) have the same
species richness (3 species) and the same
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total number of individuals (1000).
Sampling to Measure Biodiversity – Simpson’s Index of Biodiversity
Species richness and evenness can be estimated by sampling a habitat.
As species richness and evenness increase, so diversity increases.
Simpson's Index of Diversity (D) is a measure of biodiversity which takes into
account both richness and evenness.
To calculate Simpson's Index (D) for a particular area, the area must first be
sampled randomly (random sampling).
For example, the diversity of the ground flora in a woodland, might be tested by
sampling random quadrats.
The number of plant species within each quadrat, as well as the number of
individuals of each species in the samples is noted.
There is no necessity to be able to identify all the species, provided they can be
distinguished from each other.
Random samples – to avoid bias
Divide sampling site (e.g. field) into a grid and use a random number generator to
select coordinates for sampling
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Sampling Methods
1 Choose an area to sample and sampling method (based on the species)
Plants – use quadrat (a frame placed on the ground)
Flying insects / insects in vegetation – sweep net (net on a pole) –
chemicals to stun insects.
To make fair comparison
Sample randomly; same way of sweeping each time; same number of
times – on each habitat. Identify, count and record
Ground animals
pitfall trap
– small pit in
the ground)
Aquatic animals - net
A large number of traps makes results more reliable
and minimises the effects of unusual results
Insects
(ground vegetation)
Pooter
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2 Count the number of each individual species
3 Repeat the process – as many times as possible
4 Use results to estimate the total number of individuals and the total
number of species In the habitat being studied
5 When sampling different habitats and comparing them – always use the
same sampling technique and same procedure – e.g. number of
quadrats, number of sweeps with net, method of sweep, number of sweeps
– allows fair comparison
Line Transect
A line (rope or tape) taken across a habitat
Take samples along the line
Record all the plants of the sampled species
touching the line at set intervals along it
Belt Transect
Involves placing a series of frame (or point) quadrats along a line at regular intervals
and the organisms in each quadrat identified and their abundance
A belt transect gives both distribution and abundance.
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Q
A group of students is investigating the diversity of millipede (small
ground insects) in a habitat. They want to find out the species richness
and species evenness in the area.
1Describe what is meant be species richness and species evenness
2Describe how the students could measure species evenness in the habitat
Answers
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Species richness – number of different species in an area
Species evenness – a measure of the relative abundance of each species in an area
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Take random samples from the area under investigation
Use an appropriate method to capture the millipedes – e.g. a pitfall trap
Count the number of different species present and the number of individuals of each
species in the sample
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Current Estimates of Global Biodiversity
Named Species
Between 1.5 and 1.75 million species have been estimated to be present globally
by scientists.
The figures are not exact – since
- there is no central database of all species
- there are different opinions between scientists about the
classification of certain species
Unnamed Species
A large proportion of species on earth have not been named
Many species are undiscovered – or known, but not yet named
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An estimate of the total number of species is from about 5 million to 100 million –
recent estimates are around 14 million. Discrepancies in the estimates are due to:
Different techniques being used to make estimates
Lack of information for some species – e.g. bacteria and insects
Variations in biodiversity in different parts of the world due to geographical factors.
The greatest diversity is near the equator and it decreases towards the poles.
Large areas of tropical rainforests, the poles, and deserts not yet explored
Climate change affecting biodiversity
Continuing evolution and speciation
Many species becoming endangered or are becoming extinct
Estimates change as scientists find out new information
Do not take into account numbers of individual species or variation between or
within species
Therefore current estimates of global biodiversity are too low
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Example – Calculation of Simpson’s Index of Diversity (D)
Calculation of D for a single quadrat sample of ground vegetation in a field or
woodland would not give a reliable estimate of the diversity of the ground flora
Several samples would have to be taken and the data pooled to give a better
estimate of overall diversity
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D is always a value between ) and 1
The closer the index (D) is to 1, the greater the diversity
The greater the species richness and evenness, the higher the
number
A community dominated by one or two species is
considered to be less diverse than one in which several
different species have a similar abundance.
An area with a high biodiversity index
More species present - each species relies on a number of others
If one species is affected by some change, the others may be less affected
A species dependent on the one that is affected will have others to fall back on
The ecosystem (area / habitat) is more stable than one with a low biodiversity
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Species of flower
Red
3
White
5
Blue
3
Total
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Comparison of D for the 3 habitats
D
Barley field
Wheat field
Under hedge
0.62
0.61
0.86
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D is higher under hedge than in field - more different species than in other
fields
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Greater species richness; more different habitats and variety of food
under hedge – due to more plant varieties growing under the hedge
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Wheat field - mainly wheat with small number of few other species to
provide food for the insects
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Number of insects more evenly spread under hedge than open field
Use of chemicals on wheat and not on hedge vegetations – affects
species richness
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More niches for insects under vegetation
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More species of plants under hedge
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Wild species under hedge
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D is always a value between 0 and 1
The closer the index is to 1, the more diverse the habitat.
The greater the species richness and evenness, the higher the number
A community dominated by one or two species is considered to be less diverse
than one in which several different species have a similar abundance.
No need to identify organisms to species level
In an area with high biodiversity index
There are more species - each species relying on a number of others
If one species is affected by some change, the others may be less affected
A species dependent on the one that is affected will have others to fall back on
The ecosystem (area) is more stable than one with a low biodiversity
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Importance of genetic diversity in biodiversity
Genetic diversity makes it possible for a species to evolve.
Without genetic diversity plant and
(threats) in the environment, such as:
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animals will not be able to adapt to changes
Climate change
Increase in the levels of pollution
New disease
Arrival of new pests
Humans activity affects the genetic diversity of natural habitats – e.g:
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Clearing of natural vegetation – reduces size of natural habitat - reduces
Population size of the species in that habitat
Hunting or killing for protection
Iinadvertent introduction of predators and competitors
Monoculture and selective breeding reduces variation and genetic diversity of
domesticated animals and plants. Leads to extinction of some varieties within a
species – termed genetic erosion
Reduces overall gene pool for the species
Decreases genetic variation and hence the ability of the species to adapt and
evolve
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Estimates of Global Biodiversity
Refers to the total number of species on earth – this includes
Named Species
1.5 and 1.75 million species estimated globally by scientists
Figure not exact – no central database of all species; different opinions between scientists about
the classification of certain species
Unnamed Species
Large proportion of species on earth have not been named. Many species are undiscovered – or
known, but not yet named
Estimate of total number of species - 5 million to 100 million – recent estimates - 14 million.
Discrepancies in estimates due to:
•Different techniques used to make estimates
•Lack of information for some species – e.g. bacteria and insects
•Variations in different parts of the world due to geographical factors.
•Greatest diversity is near the equator and it decreases towards the poles.
•Tropical rainforests, the poles, and deserts are largely unexplored – therefore current
estimates of global biodiversity are too low
•Climate change affects biodiversity
•Evolution and speciation are continuing
•Many species endangered or are becoming extinct
Tentative – estimates change as scientists find out new things; do not take into account numbers
of individual species or variation between or within species. Current estimates are too low24
2.3.4 Maintaining Biodiversity
Objectives
Conservation of animal and plant species –
economic, ecological, ethical and aesthetic reasons
Consequences of climate change on biodiversity of
plants and animals – changing patterns of agriculture
and spread of disease
Benefits for agriculture in maintaining biodiversity of
plants and animals
Conservation of endangered species in situ and ex
situ – advantages and disadvantages of the two
approaches
Role of botanic gardens in the ex situ conservation
of rare plant species or extinct species in the wild –
use of seed banks
International co-operation in species conservation
– CITES; Rio Convention on Biodiversity
Environmental impact assessments – EIA’s (including biodiversity estimates) for local authority
planning decisions
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Maintaining Biodiversity – important for interdependence and survival of all
living organisms
Actions taken at local, national, and global levels – important for
Economic
Plants and animals as a source of food and drink – part of food chain
Clothing & footwear – cotton (plants) & leather (animals)
Drugs – morphine (analgesic) from poppiesFuels – from biomass (ethanol, biogas) – renewable
Others – wood, paper, dyes, adhesives, oils, rubber, pesticides
Ecological
Disruption of food chains – e.g. herring
salmon
bear – loss of herring causes
loss of salmon and bear population
Disruption of nutrient cycles – by decomposers (worms, insects, fungi, bacteria)
Loss of habitats – e.g. hedgerows
Habitat destruction – e.g. deforestation leads to climate change
Ethical
Moral issues – not to interfere with nature; right to exist; moral responsibility – to
conserve for future generations
Religious & spiritual – coexistence & harmony with the natural world
Aesthetic
Attractive environment – leisure, tourism (economic)
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Agricultural
Source of food – for humans and livestock; wider range of food sources in case of
disasters (e.g. potato famine -1845 – 2 varieties of potato – destroyed by disease –
caused famine)
Source of plants for cross breeding – desired characteristics ) e.g. drought & disease
resistance; faster growth; nutritional characteristics; tolerance to
climate
change, increase yield
Source of natural predators to pests – e.g. frogs, birds, hedgehogs are predators of
pests (e.g. snails)
Pollinators – insects (bees and butterflies)
Low fat; ripening at same time
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Global Climate Change & Biodiversity
Most species are adapted to survive in a particular climate due to genetic diversity
and variation. Threats to a species with low genetic diversity would include – climate
change, increase in pollution, new diseases, new pests
Changes in the climate – e.g. changes in temperature, rainfall, wind patterns –
may cause
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the migration of species to more suitable areas, or, may cause the
extinction of some.
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changes in the patterns by which diseases are spread, and,
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changes in agricultural patterns
Climate change occurs naturally, but recently there is consensus that climate
change is a result of the impact of human activity on the environment – e.g. global
warming due to the increased emissions of greenhouse gases (such as carbon
dioxide,methane, NO, H2O vapour, CFC’s, deforestation)
Climate change leads to
Increase/decrease in the temperature of the earth
The melting of polar ice caps and flooding
Emergence and spread of disease
Change in agricultural patterns
Effects on habitats
Global dimming (air pollution – soot)
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Effects on habitats
Uninhabitable area becomes habitable –(and vice versa) – increase or decrease
biodiversity
Increase or decrease in the range of some species – range limit of Sooty Copper
Butterfly has moved 60 miles north in recent decades
Migration – to more suitable areas – change in species distribution – usually
decrease biodiversity in areas the species migrate from, and increase biodiversity in
areas they migrate to
If no suitable habitat is available for a species to migrate to, or the species is a plant
– which cannot migrate, or if the climate change is too fast, the species may become
extinct. This decreases biodiversity – e.g.
Corals die if water temperature changes by just 1 or 2 degrees
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Climate Change and the Spread of Disease
Geographical range of some insects might become greater
If area becomes warmer and wetter, mosquitoes (vector of
malaria) may spread into the area and spread malaria
Spread of mosquito increases biodiversity, but the spread of the
disease could reduce biodiversity
Warmer and wetter conditions encourage spread of fungal disease – could
increase or decrease biodiversity
Climate Change and Agricultural Patterns
Changes in – temperature, rainfall, timings of seasons, frequency of flood and
drought, wind patters – will affect patterns of agriculture and biodiversity
Previously unsuitable land becomes suitable for agriculture (and
vice versa) – increase or decrease in biodiversity
Crops suitable for growing in new climate will become established –
unsuitable crops will not grow – increase or decrease in biodiversity
Extreme weather events (e.g. flood, drought, change in timing of
seasons) may cause crop failure – disrupt food chains – reduce biodiversity
Disruption of food chains and webs may occur
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Conservation & Endangered Species
Conservation refers to the attempts by humans to maintain biodiversity by preserving
organisms and environments that are at risk as a result of human activity
Endangered Species – Definition
Species (plant and animal) that are in danger of becoming extinct, unless steps
are taken to prevent it – e.g. the panda, gorilla, and black rhino. The numbers are at a
critical level (i.e. too low) for continued survival of the species.
Extinction – when the last member of a species dies
Some species have become extinct – mammoth, dodo, sabre-toothed tiger
The survival of species can be threatened for a number of reasons – including:
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Climate change
New predators being introduced
Destruction of habitats (e.g. by logging; road building) – destroys food
sources and shelter
Hunting
Competition for food, shelter, etc.
Pollutants
Poaching
Killed for food
Killing to prevent damage to farmland and settlements
Low population
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E.g. Whales
Endangered, in danger of extinction. main causes of whale deaths include
Entanglement in fishing nets and drowning
Pollutants in the sea
Colliding with ships during migration
Climate change affecting food sources
Culling and hunting
Money can be made from whales
Live whales– as a tourist attraction
Dead whales– food, oil, making cosmetics (using blubber)
Endangered species can be protected from extinction by
Education – raising awareness
Breeding animals in captivity (e.g. zoos) and returning to natural habitat
to create new population
Protecting (conserving) natural habitats
Creating artificial ecosystems (e.g. zoos, aquariums) for the species to
live in
Legally protecting endangered species – prevent trapping and captivity
Prohibiting hunting of legally protected species – permits to hunt
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issued to certain people
In situ Conservation
Conservation
– in situ (“on site”)
Involves protecting species in their natural habitat – methods include:
Protected areas – national parks; nature reserves - areas are protected from
developments (industrial, urban) and farming
Control or prevention of species that threaten biodiversity - e.g. grey
squirrels (not native) compete with native red squirrel, causing a decline in red
squirrel population.
Protection of habitats - e.g. conserving wetlands, by controlling water
levels; coppicing (trimming trees) to conserve woodlands – allows organisms to
live continuously in their natural habitat
Restoration of damaged areas – e.g. a coastline polluted by an oil spill.
Promoting particular species – by protecting food sources or nesting sites
Legal protection for endangered species – prevent hunting, logging;
countries may not agree
Minimise human impact on the natural environment
Advantages
All required conditions already present; no special provisions required – well adapted
Both species and habitat are conserved; less disruptive; chance of population
recovery is greater
Disadvantages
Difficult to control – poaching, predators, climate change
Species not accepted by other members of the species already present
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Conservation parks/nature reserves /SSSI’s
Choosing of reserve or park
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How many species represented; prevailing environmental conditions
Adequacy – is the area large enough to provide for long-term survival
Representativeness - Is there a full range of diversity within each
species and set of environmental conditions
Advantages of designating an area;
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Conservation of plants and animals in their natural environment
Permanent protection of biodiversity and ecosystems
Protects elements of natural and cultural heritage
Facilitates management of designated area – ensuring ecological integrity
Ecologically sustainable land use and associated economic benefits
Facilitates scientific research
Secure environmental future
Enjoyment of natural environment
Reserve should meet the needs of indigenous people (hunting; religious; spiritual)
– conflict may arise if not considered
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protected animals raiding crops
continued hunting of protected species for food
illegal harvesting of timber and other plant products
tourists feeding protected animals or leaving litter
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Ex situ (“off site”) Conservation
Involves removing part of the population from a threatened habitat, and placing it
in a new location. Used as a last resort
Relocation of species to safer areas
Breeding species in captivity and reintroducing them into the wild – carried out
in animal sanctuaries, and zoos.
Botanic gardens – controlled environments to conserve rare plants and
reintroduce them into the wild.
Seed (sperm) banks – frozen (or dried) seeds are stored in seed banks for long
periods of time, without losing their fertility. Provides a useful source of seeds if
natural reserves are destroyed – in famine conditions.
Advantages (reverse arguments for in the wild)
Protect individual animals or plants in a controlled environment – protected from
factors causing endangerment
Predation and hunting can be monitored and managed easily; monitor health; treat
disease; incubate eggs artificially; hand rear young – reduce mortality; manipulate
breeding (hormones, artificial insemination, artificial selection); protect from predation,
hunters; reduce competition between individuals / species
Used to reintroduce species that have migrated to other areas
Sperm (frozen) from one male – used to fertilise a large number of females; easy
transport; maintains genetic diversity – by importing sperm from another population
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Study rare biological organisms at close range
Disadvantages
Only a small number of individuals can be catered for.
Difficult and expensive to create and sustain the right environment.
Less successful than in situ methods – many species do not breed successfully in
captivity.
Species cannot adapt when introduced to their natural habitat
Problems of acceptance of introduced member by existing members
Choose individuals from different areas – maintains / increases genetic variation
(gene pool)
Choose unrelated individuals - reduces risk of inbreeding between related individuals
Less risk of losing all individuals due to environmental change (e.g. disease)
House in separate centres – less risk of losing all individuals due to natural disasters,
human action
Select higher proportion of females
Preserving of species –long term measures
Legal protection
Ban cause of endangerment
Protected areas – sanctuaries, reserves – provide breeding sites
Prevent habitat destruction
Monitoring – tagging
Education – to public on importance of the species
Sperm and egg banks; seed banks
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Inbreeding depression is a disadvantage in captive breeding - happens when closely
related individuals – e.g. a brother and a sister, mate.
Offspring are much less likely to survive and reproduce successfully – due to an
increased chance of inheriting harmful recessive alleles from both parents – an
offspring with homozygous recessive alleles may lack vital gene products and be less
likely to survive and reproduce successfully.
Zoos keep detailed records detailing the family trees of all their animals – allowing them
to ensure that individuals that mate are as distantly related as possible.
Zoos often swap animals with other zoos to promote outbreeding, to maintain genetic
diversity of the captive populations
Success of release of bred species
Healthy before release
Adequate food supply
Protected reserve
Method to monitor population
Raise public awareness
Prepare animals for survival in the wild
Gradual introduction – e.g. via semi-wild habitat
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Drying and freezing seeds for seed banks
Inhibits germination
Slows down enzymes and rate of decay - prolongs seed survival
Drying reduces damage by freezing effect
Tested regularly (every 5 years)– to check seed viability/germination
success
Allows new seeds to be produced -stored seeds may need replacing
due to decay/death
Seed banks and zoos - maintain endangered species in a protected environment –
giving protection from predators/poachers
Captive breeding programmes are used to reintroduce species into wild; enable
scientific research and education.
Seed banks (and sperm banks) occupy little space and require little attention
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CITES (Commission on International Trade in Endangered Species)
A number of Governments are signatories to a world-wide programme to protect
endangered species by conservation of biological diversity – addresses illegal
poaching and illegal trade in endangered species. CITES, agreed in 1973. Some
countries do not support conservation programmes. Aims of CITES:
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International cooperation in regulating trade and monitoring international
trade in selected species of plants and animals
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Member countries agree to make it illegal to kill endangered species
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Limiting trade in endangered species through licensing
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Illegal to trade in products made form endangered species
Black rhino - placed on Appendix 1 of CITES. Since then, their number have
stabilised and even increased. Endangered due to poaching ; destruction of
Habitat; shot to protect farmland and settlements; killed for meat and horn
Signatory countries agree – illegal to kill/poach rhino
Ban on trade in horns/hide
Increased cooperation between countries
Permits/licences issued to certain people
Education; raising awareness
Monitor habitats and species on a daily basis (wardens)
Legal action (imprisonment, fines, etc)
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RCBD (Rio Convention on Biological Diversity) - 1993
Develop international strategies on the conservation of biodiversity
Encourage and implement use of animal and plant resources in a sustainable
way
Conservation is the responsibility of each individual – as part of international law
Guidance to governments on how to conserve biodiversity
Shared access to genetic resources
Sharing of benefits arising out of the use of genetic resources
Sharing and transfer of scientific knowledge and technologies
Conservation Programmes – Benefits
•Protecting the human food supply – by maintaining the genetic variety of
crops, animals and plants
•Stabilising ecosystems by ensuring minimal damage to food chains and
habitats
•Studying and identifying plants which might be useful to develop medicines to
treat diseases
•Protecting the culture of indigenous people living in threatened habitats such
as the Amazonian rainforest
•Wild disease resistant crop variety can be bred with a non-resistant variety to
produce resistant varieties – without conservation the wild type may be lost.
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•Whaling commission (1946) - regulates whaling industry
Whaling commission (set up in 1946) – regulates the orderly development of the
whaling industry to conserve the whale population
Complete protection of certain species
Designate specified areas as whale sanctuaries
set limits on the numbers and size of whales which may be taken
Prescribe open and closed seasons and areas for whaling
Prohibit the capture of suckling calves and female whales accompanied by
calves
Compilation of catch reports and other statistical and biological records
Enforcement of international agreements (e.g. CITES) - problems
•Not all governments agree with trade policies
•Some governments corrupt
•Difficult to stop poaching and hunting in the wild
•Limited resources or will to police areas effectively
•Exported species or products may be exported under false documentation
or smuggled
•Difficult to identify endangered species – e.g. By custom officials
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Environmental Impact Assessment (EIA) and studies of biodiversity
In local planning and development it is important to assess the impact of a
proposed development (e.g. shopping centre, power station) on the environment
and biodiversity – otherwise, there may be destruction of environmentally sensitive
habitats that are rich in biodiversity. Need to conserve species that are already
protected by law
EIA ensures that decision makers consider the environmental impact of
development projects and how projects are to proceed.
To estimate biodiversity on the project site and evaluate how the
development might affect biodiversity
To consider impact on wildlife
To identify possible destruction of environmentally sensitive
habitats that are rich in biodiversity or where there are rare
species
To legally protect particular species of animals and plants
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If the need to conserve or protect is identified – need to consider whether
development should be stopped or whether other measures could be taken to
protect the species – e.g.
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Providing other suitable (similar) habitats close to the site – e.g.
Extension of mudflats on shores for the wading and migrating birds that
used the habitats that were lost to development. Successful in
attracting other bird species as well
Species of animals and plants may be protected by law
Translocation of species
Laws to protect endangered species
Estimate biodiversity on the development site and evaluating the effect
of the development on biodiversity
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International level
Promote exchange of information, consultation and notification of any development
that might affect another partner state and biological diversity
Promote the notification of any grave danger that may affect biodiversity
Promote arrangements for emergency responses to situations which may present a
danger to biological diversity
Objection to EIA studies
An EIA study needs to physically investigate the habitat – this may possibly leading to
the destruction of habitats and disturbance of the species in their habitats
May cause more disruption than the development itself
Damage to environment/ecosystem
Habitats best left alone (left to nature)
Rare species may be discovered – people stealing species for collectors
Need to consider the following in EIA:
Water resources
Drainage
Pollution
Damage & disturbance to habitat
Loss of species and loss of species diversity
Loss of habitat
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Biodiversity and importance of genetic diversity
Genetic diversity makes it possible for a species to evolve
Without genetic diversity plant and animals will not be able to adapt to changes in the
environment
Threats:
Climate change
Increase in the levels of pollution
New disease
Arrival of new pests
Humans activity affects the genetic diversity of natural habitats.
Clearing of natural vegetation – reduces size of natural habitat
- reduces population size of the species in that habitat; hunting or killing for
protection; inadvertent introduction of predators and competitors
Reduces overall gene pool for the species
Decreases genetic variation and hence the ability of the species to
adapt and evolve
Monoculture and selective breeding reduces variation and genetic
diversity of domesticated animals and plants. Leads to extinction of some
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varieties within a species –termed genetic erosion