Biodiversity. Flashcards
Biodiversity
The variety of living organisms in an area
Species
a group of similar organisms able to reproduce to give fertile offspring
Habitat
The area inhabited by a species includes physical factors like the soil and temperature.
Habitat biodiversity
The number of habitats in an are in an area
Species diversity
The number of different species and the abundance of each species in an area
Genetic diversity
the variation of alleles within a species
Systematic sampling
Samples are taken at fixed intervals along a line
Oppurunistic
Samples are chosen by an investigator will be biased
Stratified
Different areas in a habitat are identified and sampled separately in proportion to their part of the habitat as a whole
Species Richness
Number of different species in an area
Species eveness
The relative abundance of each species in an area
Simpsons index of diversity
In situ conservatism
On-site conservation involves protecting species in there own enviroment
Genetic polymorphism
- Describes a locus that has two or more alleles
- Working out the proportion of polymorphic gene loci in an organism gives you the measure of genetic diversity
Proportion of polymorphic gene loci
Number of polymorphic gene loci/ total number of loci
Factors affecting global biodiversity- Human population growth
Human population continues to grow and has done and decreases global biodiversity
Human population growth- habitat loss
- Human development is destroying habitats eg deforestation of the amazon rainforest for grazing and agriculture which decreases habitat diversity
Over exploitation
A greater demand for resources means a lot of resources are being used up faster than they can be replenished which decreases genetic diversity and species diversity
Urbanisation
Cities and road developments can isolate species meaning populations cannot interbreed and genetic diversity decreased
Pollution
High amounts of pollutants can kill species and destroy habitats decreasing biodiversity
Increased use of monoculture in agriculture
- Large areas of land are devoted to growing one crop in order to feed the growing population
- Habitats are lost in order to make way for large fields reducing habitat diversity
- Local and naturally occurring plants and animals are seen as weeds and pests so are destroyed reducing species biodiversity
Ex-situ conservation
- Off-site conservation protecting a species by removing part of the population from a threatened habitat and placing it in a new location
Advantages of Ex situ
It can be used to protect individual animals in a controlled controlled environment where hunting and predation can be monitored
Disads of ex situ
- Difficult and expensive to create and sustain the correct environment animals which are used to human contact are more suseptible to disease and is usually les successful than in situ
Ads of in situ
Both the species and the habitat are conserved and larger populations can be conserved
