conservation and biodiversity Flashcards
ecosystem diversity
range of different habitats or number of ecological niches per unit area in an ecosystem (e.g woodland may have high diversity, desert has low)
species diversity
the variety if species per unit area. this includes both the number of species present and their relative abundance
genetic diversity
range of genetic material in a gene pool or population os a species. a large gene pool leads to a high genetic diversity.
richness
number of a species in an area
eveness
relative abundance of each species in a ecosystem
simpsons recipricol index
used to describe and compare communities and their diversity. teir values can help understand the impact of human deveopment on ecosystems
diversity formula
D= Number of total individual (N-1)//number of individuals of each species(n-1)
how many mass extinctions where there
5
causes of anthropogenic species extinction
global climate change
overharvesting
pollution
invasive species
habitat destruction
eg:carribean monk seal,moas, european bison, partridge
evidence of biodiversity crisis
governmental sites that gather and collect evidence by monitering. company swissre asseses periodically
causes of ecosystem loss
land use charge for agriculture
leaching of fertilizers
urbanization
overexploitation of natural resources
mining and smelting industry
climate change
building dams
drainage or diversion of water
building dams
exampless of ecosystem loss
aras sea- evaporated
dipterocarps
moorland
ways to gather evidence of biodiversity crisis
- population size over yearrs
- range of species in a area
- diversity of a species in a ecosystem
- richness and eveness of biodiversity in an ecosystem
- monitering extent of degredation
- number of threatened species within a group
cause of current biodiverity crisis (7)
- absence of another mass extintion- masspread ecostem collapse
- hunting and overexploitation
-urbanization and land loss - deforestation and land clearence
-pollution of land and sea - spread of invasiive speaces
- overpopulation
main 2 apraches to conservation
in situ conservation
ex situ conservation
in situ conservation
preservation of species within their natural habitat
-national parks
-biosphere reserves- terrestral, marine
-natural parks or wildlife sanctuaries
ex situ conservation
preservarion of plants and animals outside their natural habitats
- seed banks crypreservation field gene banks
- botanical gardens, zoos, breading, aquariams
- home gardens
in situ conservation advatanges
- keeps organism within natural food chain/webs
- allows organisms to stay where they are adapted to
- maintains normal behaviors
- the goal is to maintain and preserve entire ecosystem
in situ disadvantage
- sometimes might not be efficient
- might lead to decrease in genetic diversity (control of immigration and emmigration)
- greater maintenance and costs involelved
advantage of ex situ
- greater control of conditions
- less competition and stress for food etc in limited space
- continuation of species that have lost their habitat permentantly
longer lifetime
ex situ disadvantage
- doesnt help to prevent the destruction of the enviorment
- limited genetic diversity species are within a shallow gene pool
- species raised in captivity are less likely to be reintroduced back into the wild
