Biodiversity Flashcards
Biodiveristy
Totality of genes, species and ecosystems in a given area
Three dimensions of biodiversity
Genetic, species and ecosystem diversity
Global factors affecting biodiversity
size, history, isolation and altitudinal range
Regional factors affecting biodiversity
Productivity, habitat architecture and habitat heterogeneity
Local factors affecting biodiversity
succession, interaction of species, disturbances and dispersal
Human factors affecting biodiversity
land use/clearance, species introduction, climate change, population growth and science advancement
Global distribution of biodivesity
Strongly correlated with latitude, highest levels generally occurring in tropical countries. But some anomalies such as Australia
Hotspot
An area containing a huge number of species a large percentage of which are endemic. Cover less than 2% but contain 44% of worlds species
Hotspot categories
Continental, large island and small island
Value of ecosystems
Goods such as timber
Regulating services such as carbon sinks
Cultural services
Supporting services like nutrient cycling
Distribution of threatened areas
Over time, species have become extinct due to climate change, catastrophic events, predation, disease and competition with other species. Various ways of auditing threatened ecosystems; economic scorecard, ecological footprint and millennium ecosystem assessment
Factors that threaten biodiversity
population growth, inequality in ownership and management, legal systems that promote unsustainable exploitation and lack of knowledge for management
Global factors threatening climate change
Climate change, deforestation and pollution
Local factors threatening climate change
Habitat change, recreational use and mineral exploitation
Disruption of ecosystems processes
Two processes are fundamental to ecosystem functioning. Energy flows which is affected by hunting or dietary changes and nutrient cycling which is affected by deforestation soil degradation
