Flashcards in Biodiversity Deck (17):
What is genetic diversity?
Estimate of gene variants (alleles) in a species
What are the two components of species diversity?
Species richness and species evenness
What is species richness?
Number of species in an area
What is species evenness?
Number of individuals of each species
What is habitat/ecosystem biodiversity?
Number of habitats (ecosystems) within an area - hardest measure of biodiversity to calculate as boundaries of habitats are difficult to determine with accuracy
What is a population?
A group of organisms of the same species
The genetic diversity of a population could increase due to...
DNA mutations, gene flow between populations of the same species
The genetic diversity of a population could decrease due to...
Selective breeding, captive breeding, genetic bottlenecks (population size reduced due to disease, habitat destruction, migration)
How can genetic diversity be calculated?
No of alleles per gene
Heterozygosity - proportion of individuals in population with 2 alleles for a particular gene
Proportion of polymorphoc genes
What are 3 human activities that can impact biodiversity?
Forestry management (and deforestation), agriculture, fossil fuel combustion
How can agriculture impact biodiversity directly and indirectly?
Deforestation, hedgerow removal, monoculture, killing organisms considered pests or weeds, eutrophication, draining of rivers and lakes for irrigation schemes
How does fossil fuel consumption indirectly impact biodiversity
Acid rain production, climate change leading to habitat destruction
What are the principal outcomes of the Rio Convention?
Targets to reduce desertification/ increase land fertility
Targets for greenhouse gas emissions
What are advantages of seed banks over botanical gardens?
Smaller so easier to store and transport
Less space required to store/ more can be stored in same amount of space
Longer term storage (remain viable for centuries)
Less risk of disease or damage
What are the advantages of in situ conservation methods?
Enables interspecies relationships to be maintained
Avoids potential problems when reintroducing species
What are the advantages of ex situ conservation methods?
Provides optimum conditions and veterinary care (medical attention)
Enables controlled breeding programmes