Geography Environment :: essays research papers

geographics NOTESSince European settlement between 78 & 100 plant species take a leak become are extinct. 150-200 under threat. GENETIC DIVERSITY - safeguard species diversity. monumental range of genetic forms within each species. Genetic variations. Extinct- goance of species later thorough searching (some extinction is natural) At risk- in danger of become 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 finical species remain , less serious category than endangeredExtinction lavatory occur naturally because of climatic change which affects the vegetation on which animals depend.MEGAFAUNA-large Australian mammals from the ice ageAborigines 50000 yrs ago modified asia Australia bridge vegetation through burning it out resulting in dry arid landscapes. This also could eat up made extinct the megafauna.In Aus since 1788 only 30% of the vegetation form u nmodified to osme degree. Cultural Vegetation means exotic or slip ind species, much(prenominal) as those found in ornamental gardens or pine plantations.The murray loved was dammed affecting surrounding habitatsIntroduced species have had a 3 fold motion on environments 1. Grazing2. 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 corresponding species of animals Hybridise- mixed breeding of plantsWildlife is harmed by recreation practisesOldest nat. park in Australia is Witches waterfall in QLD founded 1908.Rachel Carsons SILENT SPRING showed the impact that pesticides could have in areas far outside where they were applied.We are using up our renewable resources fast than we can replace themUnique plant and animal speciesLast stay rainforest in Aus is between Townsville and Cooktown, it is on the world heritage add up