Effects of Toxic Chemicals and Other Pollutants on Aquatic Ecosystems - Freshwater Ecology: Concepts and Environmental Applications - page 268

14 Effects of Toxic
Chemicals and Other
Pollutants on Aquatic
Ecosystems
Basic Toxicology
Bioassessment
Acid Precipitation
Sources and Geography of Acid Precipitation
Biological Effects of Acidification
Metals and Other Inorganic Pollutants
Organic Pollutants
Suspended Solids
Thermal Pollution
Summary
Questions for Thought
The modern aquatic environment has suffered greatly from physical
disturbance as well as organic and inorganic toxic pollution. Although the
negative effects of pollutants were recognized by scientists in the 1950s, it
was not until Rachel Carson's topic Silent Spring was published in 1962
that it became common public knowledge that organic and inorganic pol-
lutants can have strongly negative, far-reaching, and unpredictable influ-
ences on human health and ecosystems (Biography 14.1). Furthermore, acid
precipitation, thermal pollution, acid mine wastes, and increases in sus-
pended solids all cause environmental damage. The relative importance of
various types and causes of lake and river pollution have been determined
in the United States from state reports (Fig. 14.2). These data suggest that
36% of the river and stream miles and 37% of lakes are impaired. Impair-
ment is defined as having evidence of damage to aquatic life, unsuitability
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