Upsetting the Balance Food webs have developed over thousands of years and provide a balance between all animals in an ecosystem. A change of any one factor in a food web will affect all other parts of the environment. Natural process such as floods, droughts and bushfires can change the natural balance through the loss of plants and smaller animals who are often unable to escape the fires or rising flood waters. Larger animals are able to move to safer surroundings, but often die as there is not enough food available to survive. Humans also have the ability to affect a food chain, causing enormous damage. When trees are removed from a rainforest smaller animals lose their food source and this causes a reduction in their numbers. This will mean less food for the consumers of these animals in turn affecting consumers higher up in the food chain. Humans have a responsibility to keep the food chain in balance. These effects can be seen by looking at two examples - one of the most disastrous natural events in history and the use of DDT in farming.

Bibliography Scott, M. Young Oxford Books - Ecology. (London: Oxford) Time Understanding Life and Science, Ecology. (Nederlands: Time-Life, 1968) Baker, et al. Pathways into Senior Geography. (Melbourne: Nelson, 1995) Pain, Bliss & Smith. Pathways to Geography HSC Course. (Melbourne: Macmillan, 1995) The Book of Popular Science Encyclopaedia. (New York: Grolier, 1961) The Software Toolworks Multimedia Encyclopaedia, Release 6. (New York: Grolier, 1996) Snyder, et al. Biology - The Spectrum of Life. (Melbourne: Oxford University Press, 1990) Encarta 96 Encyclopaedia. (Redmond: Microsoft, 1996)