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Geography Environment

Satisfactory Essays
GEOGRAPHY NOTES

· Since European settlement between 78 & 100 plant species have become are extinct. 150-200 under threat.
· GENETIC DIVERSITY - safeguard species diversity. Large range of genetic forms within each species. Genetic variations.
· Extinct- disappearance of species after thorough searching (some extinction is natural)
· At risk- in danger of becoming extinct
· Endangered- close to extinction in the wild unless something is done the species could disappear altogether
· Vulnerable- The step before endangered
· Rare- few of a particular species remain , less serious category than endangered
· Extinction can occur naturally because of climatic change which affects the vegetation on which animals depend.
· MEGAFAUNA-large Australian mammals from the ice age
· Aborigines 50000 yrs ago modified asia Australia bridge vegetation through burning it out resulting in dry arid landscapes. This also could have made extinct the megafauna.
· In Aus since 1788 only 30% of the vegetation remains unmodified to osme degree.
· Cultural Vegetation means exotic or introduced species, such as those found in ornamental gardens or pine plantations.
· The murray darling was dammed affecting surrounding habitats
· Introduced species have had a 3 fold effect on environments 1. Grazing
2. Competition between native and introduced species 3. introduced species can introduce formerly unknown diseases.
· In recent years large amounts of insecticide and weedicide have been used and effect the food chain
· Homozygosity- breeding of the same species of animals
· Hybridise- mixed breeding of plants
· Wildlife is harmed by recreation practises
· Oldest nat. park in Australia is Witches Falls in QLD founded 1908.
· Rachel Carson’s SILENT SPRING showed the impact that pesticides could have in areas far outside where they were applied.
· We are using up our renewable resources faster than we can replace them
· Unique plant and animal species
· Last remaining rainforest in Aus is between Townsville and Cooktown, it is on the world heritage list