INTRODUCTION Human population in the past 48 years has more than doubled its seize, from 2.5 billion in 1950 to 5.9 billion in 1998 . A few month ago the Secrtary of the United Nation declared a baby as the No. 6 billion citezen of the earth. As you may have noticed, human population has reached a size that threatened our environment and the sustainability of the earth. Is the earth bounded to face this number of human? In fact, in the …showed first 75 words of 1552 total…

…showed last 75 words of 1552 total…B. 1990. Energy Demands, Gloucester Press, London Goldsmith, E. & Hildyard, N. 1988. The Earth Report:Monitoring the Battle for Our Environment, Mitchell Beazley Publishers, London. Goldsmith, E. & Hildyard, N. 1992. The Earth Report:An A-Z Guide to Environmental issues, Mitchell Beazley Publishers, London. Miller, G. T. 2000. Living in the Environment:Principles, Connections, and Solutions, 11th ed. Brooks/Cole, pacific Grove, California. Simon, J. L. & Kahn, H. 1984. The Resourceful Earth: A Response to Global 2000, Basil Blackwell Inc. New York.