Four topics related to applied research are discussed. The section on human impacts on aquatic ecosystems outlines examples of the major societal concerns regarding degradation of aquatic ecosystems and characterizes the scope and severity of the problems. These issues are presented to illustrate the diversity of challenges that face today's aquatic ecosystem scientists. Often societal and scientific opinions differ as to the relative importance of these issues. The section on technology and research needs frames the diversity of practical knowledge required to address today's aquatic resource problems. The section on scientific infrastructure discusses the academic, governmental, private, and societal foundation necessary to advance aquatic resource conservation. The final section on monitoring management strategies, details the importance of careful review of management activities as the best way to improve conservation technology and to guide future research. It promotes monitoring as a legitimate research activity equally deserving of funds.
Human-caused impacts on aquatic ecosystems are inevitable. As aquatic ecosystems evolve, society's course of action should be to understand the rate of change that is occurring and to decide whether society can, or should, intercede to slow the processes that control change. These decisions require social, economic, and scientific considerations. There are numerous human-caused environmental impacts on rivers, lakes, ground water, and wetlands. Some of these impacts are highly visible, such as draining of wetlands and flooding of large tracts of land to create reservoirs. Other impacts are not so easily observed, such as the bioaccumulation of mercury in top predators and the loss of biological diversity in lakes sensitive to acid deposition. Finally, there are undoubtedly impacts unknown to the current generation of scientists.
Under Section 305(b) of the federal Clean Water Act, states must report the status of water quality assessments to the Environmental Protection Agency (EPA). According to these state assessments, improvements in wastewater treatment have led to enhanced stream water quality in the 20 years since the Clean Water Act was first passed, but nonpoint sources of water pollution and toxic substances remain serious problems (EPA, 1994). The EPA recommends that states assess water quality based on the following individual beneficial uses:
Aquatic life support: The water body provides suitable habitat for survival and reproduction of desirable fish, shellfish, and other aquatic organisms.
Fish consumption: The water body supports a population of fish free from contamination that could pose a human health risk to consumers.