Introduction to Environmental Science [antikvár]

PREFACE Environmental science is a dynamic field of study. Since publication of the first edition of Introduction to Enviiontnental Science, scientists have learned more about the components of the environment and how they interact. They have gathered more data on the ecological relationships of endangered species, the impact of toxic materials on human health, the dispersal of pollutants in the atmosphere, the accumulation of persistent chemicals in aquatic food webs, and the control of agricultural pests with minimum application of pesticides. Equipped with this better understanding, scientists are now refining models of environmental systems and predicting more accurately the consequences of environmental change—both natural and human-related. Since the first edition, much has happened as well in the arena of environmental issues. Some issues have gained in importance while others have gradually receded from the public eye. Today, acid rain and management of hazardous wastes are receiving considerable attention from the scientific community and the media. On the other hand, con-stmction of numerous wastewater treatment plants has significantly lessened the impact of some water pollutants on aquatic ecosystems, and so water pollution has faded somewhat from public awareness. While progress has been made in understanding and mitigating some environmental problems, others require more research and remedial action. With steady improvement in the quality of outdoor air, interest is shifting to the quality of indoor air. Although the quality of surface waters (lakes and riv- ers) has improved somewhat, the quality of groundwater continues to be threatened by improper disposal of toxic chemicals. Furthermore, resolution of some environmental issues is perhaps less urgent now than it appeared only a few years ago. Atmospheric scientists have discovered that in spite of dire warnings, the ozone shield is still intact. Conservation efforts and the global oil surplus have given us a little more time to plan for the inevitable depletion of traditional energy resources (fossil fuels). Because of this dynamic nature of environmental science and issues, it is a challenge to write an up-to-date textbook on these subjects. In this edition, we meet this challenge much as we did in the first, by emphasizing scientific principles and the natural functioning of the environment. Although the importance of certain environmental issues may wax and wane with time, the underlying principles that govern the function of physical and biological systems do not change. Hence, the readers' grounding in basic concepts provides them with the interpretive skills and flexibility needed to analyze new environmental issues as they arise. Organization and Content Introduction to Environmental Science remains both a basic science text and a text on environmental issues. This is reflected in the organization of the text's 20 chapters: The basic principles of ecology are introduced in Part I and then applied to a wide variety of environmental concerns in Parts II and III.