Biodiversity Flashcards
What is biodiversity
the variety of life on earth, diversity at the genetic level, diversity of species, habitats and ecosystems
ways to measure biodiversity
distribution if ecosystems of different types
total number of species in an area
the number of endemic species
genetic diversity
What factors can biodiversity relate to
genetic resilence and diversity within a species
species reproduction and dispersal
climate tolerance of species
habitat
what is species richness
number of species present in a sample, ecosystem, landscape, region
what is species abundance
the sum total of individuals from a given species within a given area
what are the drivers of biodiversity loss
land use change, loss of habitat
climate change
pollution
over exploitation
invasive species
Why is habitat fragmentation a bad thing and whose theory backs this up
smaller areas support fewer species according to macarthur wilsons theory of island biogeography
How does climate change affect biodiversity
ecosystems vulnerable to climatge change and lacl ecological tolerance
how does pollution and over exploitation affect biodiversity
pollution events can have lasting impacts in smaller areas and air pollution can have impacts across continents
how do invasive species affect biodiversity
jump dispersal through anthroprogentic activity eg trasnport farming or gardens
island biota are particularly vulnerable due to finite resources
why should biodiversity be retained
ethics
ecosytem services eg protect soil, watershed, climate
resouce value eg food, medicine
ways biodiversity can be protected
habitat protection via national parks
international research agendas
international agreements
captive breeding
public awareness
what are the benefits of forests
environmental goods eg food
regulating services eg climate
supporting services eg soil formation
cultural services eg spiritual
woodfuel eg 2.6 bn rely on
What are the characteristics of temperate forests
found in europe, n us, china, nz
temp 7-18*c, 500-2500mm rain
decidous/ mixed coniferous
What are the characteristics of a tropical rainforest
equatorial zone, >25*c, >2500mm, centre of biodiversity and primary productivity
What are the characteristics of a boreal (taiga) forest
northern softwood forest, scandi,canada, siberia, temp -5+*c, 500-2000mm of mostly snow, low species diversity
According to UN FAO, how is a forest defined
land with tree cover more than 10% and in an area more than 0.5 ha
trees should reach at least 5m height at maturity
How to calculate net deforestation rate
afforestation- deforestation
what are the historical drivers of deforestation
agriculture and animal husbandry
harvesting timber for fuel and building
expansion if population
what are the recent drivers of deforestation
socio-economic pressures driving poor to forest frontier
governemtn policy for migration, infrastrucure and resources
international markets for forest and agriculture products
what are three causes of deforestation
ranching
development of roads and infrastructure
commodity driven deforestation eg plam oil
what are the local impacts of deforestation
soil degradation
increased sediment yield in rivers and reduction in capacity in reservoirs
social impacts
local loss of biodiversity
landslides
what are regional effects of deforestation
flooding due to no tree roots and a quicker route to rivers
regional climate change eg reduction in rainfall in amazon
what are solutions to deforestations
international agreements- although who is to hold countries to account
forest restoration/afforestation
