Reduction of biodiversity— the ultimate disaster?

Abstract

Complex biological processes maintain the stability of the global climate and bioproductivity, which affect the atmospheric gases; anything which adversely affects this balance can reduce the earth’s biodiversity and disturb the functioning of its thermostat. The explosive growth of human population lies at the root of the “quiet hazards”, those that threaten huge areas of the globe with disasters such as soil erosion and ecological destruction.

Accelerating changes in the life support systems have impacts on human society that are difficult to predict. Topsoil erosion at 0.7% per year is a serious problem for sustainable food production. Expanding population, the need for increased production and monocultures are major causes of soil erosion with forests destroyed, poor soils invaded to expand production, and irrigation leading to soil salinization. Climatic fluctuations coupled to soil erosion are a major cause of falling crop yields. Population growth has been assisted by the use of energy in food production, but this has resulted in increased carbon dioxide in the atmosphere and consequent temperature rises. Solutions to the problem lie in the use of cleaner energy sources, including nuclear, solar and geothermal. With human activity being the greatest factor for change on the earth, earth scientists have an expanding role to play in understanding the limits to resources and the global thermal balance. An ecocentric philosophy of development requires such an understanding, and the necessity of facing realistic population control.