4.2- Biodiversity Flashcards
What is the definition of biodiversity?
The variety of living organisms in an area
What is the definition of a species?
A group of similar organisms are able to reproduce to get fertile offspring
What is the definition of a habitat?
An area inhabited by species. It includes the abiotic factors and biotic factors
What are the three different levels of biodiversity can be considered on?
Habitat diversity
Species diversity
Genetic diversity
What is the definition of habitat diversity?
The number of different habitats in an area
What is the definition of species diversity?
The number of different species (species richness) and the abundance of each species (species evenness) in an area
What is the definition of genetic diversity?
The variation of alleles within a species
What are the different types of a non-random sampling?
Systematic
Opportunistic
Stratified
Why should samples be taken at random?
To avoid bias in your results
What is the definition of systematic sampling?
When samples are taken at fixed intervals
What is the definition of opportunistic sampling?
When samples are chosen by the investigator
It is simple to carry out but the data will be biased
What is the definition of stratified sampling?
When different areas in a habitat are identified and sampled separately in proportion to the habitat of a whole
Why is it sometimes necessary to take a non-random sample?
Eg. When there’s lots of variety in the distribution and you want to make sure all the different areas are sampled
What is species richness?
The number of different species in an area
What is species evenness?
A measure of the relative abundance of each species in an area
If a habitat has a great species richness and a high species evenness, what will happen to the biodiversity?
It will be high
How is biodiversity measured?
Using the Simpsons index of diversity
What is the formula for the simpsons index of diversity?
D=1-(sum of(Total number of individuals of 1 species/Total number of organisms of all species)^2)
A habitat has a simpsons index of diversity equal to 0. What does this mean?
It is not very diverse
A habitat has a The Simpsons index of diversity equal to 1. What does this mean?
It is very diverse
What could occur if a population has a low genetic diversity?
They might not be able to adapt to change in the environment in the whole population could be wiped out buy disease
What does polymorphism describe?
A locus that has two or more alleles
What are the three main factors that affect global biodiversity?
Human population growth
Increased use of monoculture in agriculture
Climate change
How does human population growth decrease biodiversity?
Habitat loss
Overexploitation- greater demand for resources
Urbanisation can isolate species
Pollution can destroy habitats
How does increased use of monoculture in agriculture decrease biodiversity?
Habitat are lost as land is cleared
Plants destroyed with pesticides
Varieties of crops that don’t make enough money and not planted anymore
How does climate change affect biodiversity?
A changing climate can increase or decrease the habitable areas of some species (this can increase or decrease biodiversity)
Species may be forced to migrate which shuffles biodiversity around (species can even go extinct)
Why is maintaining biodiversity important? (ecological reasons)
To protect species, including keystone species
To maintain genetic resources
Why is it important to protect species, including keystone species?
Organisms in an ecosystem are interdependent
The loss of just one species can cause disruption of food chains and disruption of the nutrient Cycle
What’s a keystone species?
Species which many other species in an ecosystem depend on and without them, the system will change dramatically
They can be Predators modifiers or hosts
Why is it important to maintain genetic resources?
Genetic resources provide us with a variety of everyday products such as food, clothes, industrial materials and drugs
What is an economic reason for maintaining biodiversity?
To reduce soil depletion
What is soil depletion?
When nutrients required by crops are gradually used up. It is caused by continuous monoculture and has a large economic cost of fertilisers
What are the three main reasons to maintain biodiversity?
Ecological reasons
Economic reasons
Aesthetic reasons
What is a genetic resource?
Any material containing genes which we find valuable
What is an aesthetic reason for maintaining biodiversity?
Areas rich in biodiversity provide attractive landscapes that people can enjoy
What is in situ conservation?
Protecting species in their natural habitats
What is ex situ conservation?
Protecting a species by removing part of the population from threatened habitats and placing it in a new location
It is often used as a last Resort
What are 4 methods of in situ conservation?
Establishing protected areas such as national parks and wildlife reserves
Controlling the introduction of species that threaten local biodiversity
Protecting habitats- controlling water levels to conserve Wetlands
Giving legal protection to endangered species
What are 4 methods of ex situ conservation?
Relocating an organism to a safer area
Breeding organisms in captivity and then reintroducing them
Botanic gardens
Seed Banks
What or some advantages of in situ conservation?
The species and habitats a conserved
Larger populations can be protected and it’s less disruptive
What is a disadvantage of in situ conservation?
It can be difficult to control some factors that are threatening a species
What is an advantage of ex situ conservation?
Can be used to protect individual animals in a controlled environment and threats can be managed more easily
What is a disadvantage of ex situ conservation?
Only a small number of individuals can be cared for
It can be difficult and expensive to create the right environment
It is less successful in situ methods
What are botanic gardens?
Controlled environment used to grow variety of rare plants
What are seed Banks?
Places where seeds are frozen and stored.
They provide a useful source of seeds if natural reserves are destroyed
How does the Rio Convention on biological diversity (CBD) help conserve biodiversity?
It makes it international law but conserving biodiversity is everyone’s responsibility
It provides guidance to government on how to conserve biodiversity
How does the CITES agreement help conserve endangered species?
The member countries all agree to make it illegal to kill endangered species
Agreement makes it illegal to trade products made from endangered species
What is the CITES agreement?
An agreement designed to increase international cooperation in regulating trade in wild animal and plant specimens
What is the countryside stewardship scheme (CSS)?
A local scheme in the UK that aims to conserve wildlife and biodiversity
Agreement offered to pay landowners who followed management techniques
