Executive Summary

From ancient times, civilizations have depended on freshwater bodies—lakes, reservoirs, rivers, and wetlands. Fresh water is essential not only to sustain human life but also to support the activities that form the basis for thriving economies. At the same time that water resources are essential to human societies, activities of these societies can pollute and degrade water resources, limiting their beneficial uses. Since the start of the ''environmental movement" in the 1960s and especially since the passage of the Clean Water Act in the United States in 1972, North Americans have realized that manufacturing, agriculture, mining, urban development, and other activities can pose risks to freshwater bodies, and they have taken steps to reduce these risks.

Recently, the U.S. Congress has called for reevaluation of environmental laws, such as the Clean Water Act, based on risk analysis. In theory, risk analysis would indicate the most serious threats to environmental resources, identify the most cost-effective methods to reduce risk, and evaluate whether existing laws provide cost-effective solutions or address secondary threats at high cost. Such risk analysis cannot be carried out in the absence of sound science. For freshwater bodies, risk analysis requires knowledge of how human land use affects the physical, chemical, and biological characteristics of the aquatic ecosystem.

One of the critical sciences required to understand how human actions and natural processes affect lakes, reservoirs, rivers, and wetlands is limnology. Limnology is a multidisciplinary science that integrates the basic sciences (biology, chemistry, physics, and geology) in order to study inland waters as complex ecological systems. Only through such integrated study will it be possible to understand the full range of human impacts on aquatic ecosystems. As the nation has recognized that its resources for addressing environmental problems are limited, the science of limnology has become increasingly vital for devising cost-effective strategies to ensure that freshwater systems not only can serve this generation but also can be preserved for the benefit of generations to come.



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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology Executive Summary From ancient times, civilizations have depended on freshwater bodies—lakes, reservoirs, rivers, and wetlands. Fresh water is essential not only to sustain human life but also to support the activities that form the basis for thriving economies. At the same time that water resources are essential to human societies, activities of these societies can pollute and degrade water resources, limiting their beneficial uses. Since the start of the ''environmental movement" in the 1960s and especially since the passage of the Clean Water Act in the United States in 1972, North Americans have realized that manufacturing, agriculture, mining, urban development, and other activities can pose risks to freshwater bodies, and they have taken steps to reduce these risks. Recently, the U.S. Congress has called for reevaluation of environmental laws, such as the Clean Water Act, based on risk analysis. In theory, risk analysis would indicate the most serious threats to environmental resources, identify the most cost-effective methods to reduce risk, and evaluate whether existing laws provide cost-effective solutions or address secondary threats at high cost. Such risk analysis cannot be carried out in the absence of sound science. For freshwater bodies, risk analysis requires knowledge of how human land use affects the physical, chemical, and biological characteristics of the aquatic ecosystem. One of the critical sciences required to understand how human actions and natural processes affect lakes, reservoirs, rivers, and wetlands is limnology. Limnology is a multidisciplinary science that integrates the basic sciences (biology, chemistry, physics, and geology) in order to study inland waters as complex ecological systems. Only through such integrated study will it be possible to understand the full range of human impacts on aquatic ecosystems. As the nation has recognized that its resources for addressing environmental problems are limited, the science of limnology has become increasingly vital for devising cost-effective strategies to ensure that freshwater systems not only can serve this generation but also can be preserved for the benefit of generations to come.

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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology Because of the increasing importance of interdisciplinary aquatic science in solving environmental problems, in 1994 the National Research Council appointed an expert committee, the Committee on Inland Aquatic Ecosystems, to recommend ways to strengthen limnology programs within U.S. educational institutions. The committee included limnologists and aquatic scientists in related fields from academia, state and federal government, and the private sector. This report presents the committee's findings. It reviews the history of limnology and its role in solving contemporary water problems. Based on this history and society's current needs, it recommends improved ways to educate future limnologists. Traditionally, limnologists have been perceived as scientists who study primarily the biological properties of lakes. However, modern limnologists define their science broadly; they view it as covering the biology, physics, and chemistry of all inland waters, including rivers and wetlands as well as lakes. Some scientists who study primarily streams or primarily wetlands, including several committee members, identify themselves as limnologists as well as stream or wetland scientists, while others do not. Regardless of where one draws the line in deciding whom to call a limnologist, lakes, rivers, and wetlands are interconnected, and the sciences that study them are closely allied. Understanding of lakes is incomplete without some knowledge of how wetlands and rivers affect them, and vice versa. Whether or not one agrees with the broad definition of limnologist, limnology can serve as a paradigm for interdisciplinary water science in general. Improvements in the teaching and study of limnology will benefit other, closely allied aquatic sciences—as well as society as a whole—by leading to new research breakthroughs and raising the profile of both aquatic ecosystems and the sciences necessary for understanding how to protect them. CONTEMPORARY WATER MANAGEMENT: ROLE OF LIMNOLOGY The Clean Water Act and other efforts to control waste discharges to waterways have noticeably improved the condition of some water bodies (well-known examples include Lake Erie and the Potomac River), but many lakes, rivers, and wetlands in the United States remain degraded or at high risk. For example, the Environmental Protection Agency recently reported to Congress that 44 percent of river miles are unsuitable for one or more of the uses (boating, swimming, or fishing) designated by state water managers, and 57 percent of lakes are unsuitable for one or more of these uses. The causes of this degradation extend beyond the pollution sources that have been the focus of pollution control efforts over the past 25 years (primarily direct wastewater discharges from industries and

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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology sewage treatment plants); they include various diffuse pollution sources, as well as a variety of physical stresses that directly or indirectly affect aquatic habitats. Limnologists, working with other aquatic scientists, have been involved in developing ways to optimize the preservation of inland waters: Watershed management: Maintaining and improving the quality of surface waters will require consideration of how the wide variety of human activities on the land surrounding water bodies (their watersheds) affects water quality. Limnologists have been involved in demonstrating how land-use changes alter the yields of chemical constituents and sediments to water bodies, and they should be instrumental in devising scientifically based watershed management plans. Wetland preservation: Substantial losses of wetlands have occurred in the past. Recognizing the valuable role of wetlands in providing habitats for important species, reducing flood peaks, and filtering runoff before it enters lakes and rivers, the United States has developed a policy intended to prevent further net loss of wetlands. Research by limnologists will be essential for developing a workable way to implement this policy. Control of cultural eutrophication: Eutrophication—the input of excess nutrients (especially phosphorus and nitrogen) to lakes and rivers from sewage, agricultural fertilizers, and other sources—results in the development of large masses of algae and (often) large aquatic plants. The algae decrease water clarity, deplete deep-water oxygen to the degree that important species of fish cannot survive, and may create taste, odor, and toxicity problems. Work by limnologists has been and will continue to be central to developing plans to control nutrient inputs in order to restore ecosystems as large as Lake Erie and as small as farm ponds. Reservoir management: More than 80,000 dams exist in North America. Limnologists, working with hydraulic engineers, hydrologists, and fisheries biologists, need to play key roles in developing the scientific understanding necessary to manage the impoundments created by dams and to optimize dam operations to preserve water quality below the dams. Study of the effects of global warming: Nations worldwide have been discussing strategies to mitigate the impacts of global warming. Limnological studies can shed light on how global warming—which could alter water supply, water temperatures, and related habitat factors—may affect aquatic ecosystems. Evaluation of toxic pollutants: The release of toxic substances in trace quantities once was thought to cause little harm to the environment, but aquatic scientists have shown repeatedly that such substances can accumulate in fish and fish-eating birds to levels up to 10 million times greater than those in lake water, resulting in health advisories against

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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology fish consumption. Continued limnological research will provide a more complete understanding of the behavior of toxic substances in aquatic environments. Assessment of damage from acid rain and other airborne pollutants : Nations around the world have signed treaties to control acid rain. Limnological research is increasing the understanding of long-term effects of acid rain on aquatic communities, leading to improved predictive models and mitigation and restoration techniques. Control of exotic species: Numerous exotic species (both plants and animals) have disrupted aquatic ecosystems in North America, sometimes with high costs. For example, the zebra mussel, accidentally discharged into the Great Lakes with the ballast water of an oceangoing ship in 1986, will cause an estimated $4 billion in damages before the turn of the century, primarily because of clogging of water intake pipes and loss of native mussels and clams. Research by limnologists is a key component of plans to control the undesired proliferation of exotic plant and animal species. Prevention of species extinction: According to some estimates, at least 30 percent of all North American fish species are rare, at risk of extinction, or extinct. Limnological research can help determine more accurately the distribution of native species, the factors that influence their success in certain habitats, the effects of species loss on aquatic communities, and how best to protect critical species. In the past, water management decisions have often been made in isolation, without adequately considering the synergistic relationships among a variety of isolated actions. For example, the Clean Water Act focused primarily on reducing water pollution from sewage and industrial facilities and paid much less attention to the range of other human impacts on water bodies. Future water management will demand professionals who are broadly trained to view water bodies as systems that are integrated with the surrounding landscape and in which biological, physical, and chemical processes are interrelated. Education in limnology provides the type of broad perspective needed to understand how water bodies behave in environments without significant human influence and how they are affected by human activities. This broad perspective is essential for any strategy that aims to control environmental problems by considering the full range of risks and benefits. STATUS OF LIMNOLOGY IN THE UNIVERSITY SYSTEM Because most of the early limnologists were trained in biology, professors of limnology historically have been housed in departments of biological science (including zoology and botany). However, during the second

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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology half of the twentieth century, increased funding for pollution studies of freshwater bodies has drawn scientists from a wide range of fields to limnological research. Today, scientists who study problems in limnology operate from departments as diverse as civil engineering, fisheries and wildlife, botany, zoology, ecology, environmental science, forestry, geology, and geography. For example, in a survey conducted for this report, universities listed 23 types of departments where scientists teach and conduct research in limnology. The net result is increasing fragmentation of the discipline: limnology is an interest within many fields, but it is not the primary focus of any of the traditional departments. One problem caused by the fragmentation of limnology in the university system is that students who display interest in limnology during their undergraduate years often lack guidance on the mix of courses needed to prepare them for further work in the field. Because U.S. colleges and universities generally do not offer formal undergraduate majors specifically identified as "limnology," students often enter the field accidentally, by taking limnology as an elective within another science major. A second problem resulting from the fragmentation of limnology is lack of adequate support for laboratory and field programs. Given the tight funding at many universities and the lack of strong departments or interdepartmental programs to serve as advocates for limnology, funding is often insufficient to provide laboratory and field experience for interested students. Typically, laboratory and field courses in limnology must be limited to a small number of students even though laboratory and field studies are critical parts of education in limnology. A third problem stemming from fragmentation is that graduate students in limnology may not receive adequate training in all of its important subdisciplines. For example, students who obtain their limnology degrees through biology departments might have strong training in fields such as organismal physiology but much weaker knowledge of water chemistry and physical limnology. On the other hand, students specializing in the study of aquatic ecosystems in civil and environmental engineering departments may have strong training in hydrology and water chemistry but relatively little knowledge of the organisms that inhabit aquatic systems. Also, students in these and other types of programs rarely have access to courses that will train them to understand all types of aquatic ecosystems (wetlands, streams, and lakes). EDUCATION IN LIMNOLOGY: RECOMMENDATIONS FOR CHANGE Education in limnology, and the strength of the science in general, will depend on providing better coordination of limnological teaching and

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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology research. The Committee on Inland Aquatic Ecosystems recommends two possible administrative ways to achieve this coordination: Establish regional departments of aquatic science with limnology majors. Creating strong aquatic science departments, with comprehensive limnology majors for undergraduates, in some U.S. universities on a regional basis would establish centers of strength for this science. Establish strong interdepartmental programs in aquatic science, with an option to specialize in limnology. Interdepartmental programs may be easier to establish than new departments and can have the advantage of encouraging collaborative work and providing students with access to large numbers of formal courses. On the other hand, faculty loyalties to their primary departments and lack of budgetary authority may be impediments to successful implementation of interdepartmental programs. The approach appropriate for a given institution will depend on the institution's existing strengths, as well as on the preferences of its faculty and leadership. Strong support from the university administration is essential for the success of interdepartmental programs in order to avoid such practical problems as dividing overhead costs among departments, cross-listing courses, and approving joint appointments. In addition to instituting well-coordinated programs in limnology, the Committee on Inland Aquatic Ecosystems recommends several other initiatives to improve education in limnology. These actions are needed to (1) inform responsible citizens who will value freshwater ecosystems and understand water resource issues, (2) provide a basic understanding of the science for all who will be involved in decisions and actions that affect freshwater ecosystems, and (3) train future research scientists who will work to advance the understanding of aquatic ecosystems. Following are recommendations for improving limnological education to serve each of these purposes: Educating responsible citizens: General introductory courses in limnology should be developed and taught at all types of universities and colleges. These courses should include coverage of wetlands and streams as well as lakes, and they should be accessible to all students, with the goal of conveying how freshwater ecosystems function and how they respond to various human activities. Enough faculty support should be provided to allow all interested students to enroll in an introductory limnology course and as many as possible to undertake field and laboratory work. Educating future water managers: Students should be provided with increased opportunities to gain exposure to practical problems such as the management of freshwater systems in urban areas, in national parks, on grazing lands, and on croplands. Student internships in federal and

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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology state agencies and the private sector are one way of providing this exposure and simultaneously furthering the links between universities, agencies, and private firms. Prospective managers of aquatic ecosystems should have the opportunity to gain laboratory and field experience in limnology. Educating future limnologists: Undergraduates showing special interest in limnology need to be given guidance and opportunities to select a curriculum that will provide the breadth of skills and knowledge required to solve problems of freshwater ecosystems. Opportunities for undergraduate students to attend summer- or semester-long limnology "field camps" should be developed to complement the laboratory portion of conventional limnology courses. At the graduate level, comprehensive programs need to be developed, especially for M.S. degrees, to train limnologists who are knowledgeable across the spectrum of freshwater ecosystem types; who have an integrated understanding of the physical, chemical, and biological processes operating in these ecosystems; who understand the political, economic, and cultural factors that affect aquatic ecosystems and their management; and who have strong problem-solving and communication skills. Graduate programs need to include a research or practical problem-solving component; "course-work only" M.S. programs generally are not adequate to provide limnologists with the above-described skills. LINKING WATER MANAGEMENT, RESEARCH, AND EDUCATION IN LIMNOLOGY Beyond strengthening limnology in educational institutions, the Committee on Inland Aquatic Ecosystems recommends additional steps to improve the links between scientific understanding in this field, as produced and disseminated primarily by educational institutions, and the practical management of water resources, as conducted primarily by government agencies and for-profit companies: Support of aquatic science research: The National Science Foundation should establish a permanent program focused on basic and problem-solving interdisciplinary research on inland aquatic ecosystems. Certification of limnologists: Leaders of the limnological professional societies should consider establishing professional certification programs in limnology. Such a tactic could raise the value and profile of degrees in limnology and help ensure a minimum level of competence among practicing limnologists. Certification might be based on assessment of an applicant's educational and work experience by a qualified review board. Professional certification programs have pluses and minuses, but a number of environmental science disciplines (for example, hydrology and

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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology ecology) and associated professional societies have decided that the former outweigh the latter and have begun certification programs in recent years. Creation of a federal job classification for limnologists: Establishment of a federal job classification titled "limnologist" would help agencies to identify scientists for water resource management and research positions in which limnological knowledge is essential. Currently, limnologists are classified as "hydrologists" or "microbiologists" by the federal government, making it difficult for agencies to identify job candidates with the training required for many water-related positions. Involvement of water managers in teaching and graduate advising: Appointing scientists from federal and state agencies and private consulting firms to serve as adjunct professors can benefit practicing professionals by providing them with access to the newest scientific information and can benefit universities by providing students with the opportunity to learn about applied resource problems from practicing professionals. Adjunct professorships also may facilitate student access to internships and other student appointments in government agencies and provide all students with experience on a team studying a practical problem. Although such adjunct faculty appointments need to be handled and monitored with due attention to protecting the interests of all parties and the integrity of academic programs, there is ample precedent for successful academic-government and academic-private sector linkages in other natural resource and engineering fields. Providing university-based continuing education opportunities for water managers: One of the most direct ways for universities to obtain feedback on the practical relevance of curricula in limnology is by providing continuing education opportunities for water managers. Continuing education courses allow water professionals to improve their comprehensive understanding of ecosystems and to learn newly developed scientific techniques, while providing professors with insights about the questions of most importance to professionals in the field. Increasing public awareness of limnology: Limnologists can work at several levels to increase public awareness of their field. Examples of possible outreach efforts include participating in elementary and secondary school education, speaking at public hearings, working with university extension services, providing advice to environmental organizations, and participating in citizen-based programs for water quality monitoring and rehabilitation. In summary, determining the most significant risks to freshwater ecosystems and deciding how to manage those risks effectively will require advances in fundamental science and in the application of this knowledge

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Freshwater Ecosystems: Revitalizing Educational Programs in Limnology to practical problems. In turn, achieving these goals will require strengthening limnology within university systems and making better connections among academic limnologists, water resource managers, and the general public.