Biodiversity Case Studies, Contested Planet Unit 3 A2


The impacts of Global Warming on biodiversity in the Arctic

Changes in arctic ecosystems will have global impacts because of the links between the arctic and ecosystems much further south – migrant bird species, depend on summer breeding an feeding grounds in the Arctic. In the future migrant birds will have to fly further north and spend more time searching for suitable breeding/feeding areas.

·         Localised shifting of ecosystems in a poleward direction – coniferous forests will expand to the tundra zone, which will spread into fragments areas of polar desert

·         Tundra will shrink as rising seas levels drown coastal areas

·         Increase in forest fires and insect infestations; reduce both biomass and biodiversity

·         Marine life will respond to warmer sea temperatures and reduced ice cover; improved food supplies will mean bigger fish stocks and the possible emergence of new species

·         Fragile food webs could easily be damaged – loss of tundra mosses and lichens that provide the main food for caribou – declining deer numbers wi8ll affect the species that hunt them, wolves/arctic foxes

Invasive species in the Galapagos

Off the coast of Ecuador; the Galapagos qualify as a hotspot on the basis of their endemism and the sever threat facing the unique ecosystem. A huge range of alien species were introduced from the Ecuadorian main land by people seeking to make a living from FISHING and TOURSIM.

·         60% of the 180 endemic plant species are threatened

·         490 recorded introduced insect species – of these 55 are ‘high risk’ with the potential to cause severe damage to native biodiversity.

·         Ne vertebrate species arrive every year and aggressive invasive species such as mainland snake predators could soon establish themselves.

Actions have been taken to preserve endemism in the Galapagos: eradication of introduces rodents/feral cats, removing the quinine tree one of the most serious plant invaders. Many other pressures – including that of tourism, thousands of visitors each year.

Masai Mara game reserve: a degraded area

Break down in management = decline in the general stage of its grassland ecosystems. The park fees paid by tourists are meant to go towards protecting the reserve and providing social services for the local tribesmen. Little of the money has reached its intended destination; the park rangers were not properly paid and lacked basic equipment and thus could do little to stop the widespread and illegal hunting of game that tourists wanted to…




Thanks a lot, nice to see some quite concise notes on the biodiversity case studies for once, very helpful!! Cheers