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3
Focus on Monitoring to Build Better Understanding of Our Ecological Systems

Long-term monitoring serves as a basis for both the understanding of our ecological systems and the measurement of our progress toward ecological goals. The focus of this monitoring should not just be on the goal as the end point of these activities, but on the rate of change we are making toward achieving those goals (see Chapter 8).

People commonly make comparisons between today and the past on the basis of their memories—anecdotal comparisons like "winters aren't as cold as when I was a child." However, scientific comparisons of the physical or biological environment require solid evidence measured as quantitatively as possible. Data need to be recorded according to a carefully prescribed protocol so that measurements over extended periods or taken simultaneously in different locations can be plausibly compared with one another. When properly collected, these data can serve one or more of five useful purposes.

  • Detection of short-term changes and long-term trends from measurements of a particular scientific variable made at regular intervals.

  • Establishment of existing, baseline conditions in advance of planned or unplanned changes in an environmental system.

  • Determination of whether a particular planned activity has been properly implemented.

  • Assessment of the effect of a planned activity.

  • Provision of data for scientific research.

Some environmental variables have been measured for a long time. For example, extensive temperature records (maximum, minimum, average) exist for a large number of locations, including cities and ships at sea, for more than a century.



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Linking Science and Technology to Society's Environmental Goals 3 Focus on Monitoring to Build Better Understanding of Our Ecological Systems Long-term monitoring serves as a basis for both the understanding of our ecological systems and the measurement of our progress toward ecological goals. The focus of this monitoring should not just be on the goal as the end point of these activities, but on the rate of change we are making toward achieving those goals (see Chapter 8). People commonly make comparisons between today and the past on the basis of their memories—anecdotal comparisons like "winters aren't as cold as when I was a child." However, scientific comparisons of the physical or biological environment require solid evidence measured as quantitatively as possible. Data need to be recorded according to a carefully prescribed protocol so that measurements over extended periods or taken simultaneously in different locations can be plausibly compared with one another. When properly collected, these data can serve one or more of five useful purposes. Detection of short-term changes and long-term trends from measurements of a particular scientific variable made at regular intervals. Establishment of existing, baseline conditions in advance of planned or unplanned changes in an environmental system. Determination of whether a particular planned activity has been properly implemented. Assessment of the effect of a planned activity. Provision of data for scientific research. Some environmental variables have been measured for a long time. For example, extensive temperature records (maximum, minimum, average) exist for a large number of locations, including cities and ships at sea, for more than a century.

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Linking Science and Technology to Society's Environmental Goals The nation's future environmental goals should be to maintain the progress made thus far.…We would not want to see water or air pollutants increase, nor would we want to undo proper handling of hazardous wastes. Nonetheless, every area of current environmental activity should be reassessed and priority given to the areas most affecting public health—long-term, as well as short-term health. Ecological concerns that do not relate to public health deserve serious consideration but should not be presumed to have transcendent intrinsic worth. The loss of a subspecies must be weighed against the costs visited on ordinary citizens. All risks should be considered in the context of natural hazards and assumed risks. While there is no magic cutoff for acceptable risk, rankings of the cost of risk avoidance and of natural and man-made risks can help to defuse the hysteria that causes an allocation of resources to low-risk, high-cost concerns. —Forum Participant Comment As particular environmental concerns became prominent, systems of measurement were put into place to provide the needed information. The interest in temperatures and rainfall led to the establishment of national weather bureaus, which then proceeded to add other dimensions as demands arose. Some of the data systems use relatively simple instruments and training, as with the thousands of amateur observers around the United States who report daily measurements. Others are highly sophisticated, such as the satellites that furnish the images that record the approach of tropical hurricanes. Some need to be global because the phenomena being investigated and recorded occur on a global scale—for example, satellite measurements of stratospheric ozone. Although the desirability of directly comparable measurements has long been recognized, the great majority of environmental data collected over the last several decades fails to meet this criterion. Most scientific environmental research has the primary goal of understanding a particular system at one time and in one place, and only later and separately does the question of whether this understanding is substantially different in another place or in the same location at some future time arise. Science and technology can contribute to achieving environmental goals by identifying and developing improved data-collection methods, systems and sensors that are faster, have wider collection area(s), and are less expensive, more accurate, and more remote. —Forum Participant Comment Environmental monitoring has been going on in a quantitative instrumental manner since before the 1870s. In general, the development of research efforts in long-term environmental monitoring originated first in the geophysical sciences and only much later spread to the biological sciences.

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Linking Science and Technology to Society's Environmental Goals Knowledge Advances Needed for Development of Sound Environmental Management Goals Setting Goals What is the distribution of biodiversity in the U.S.? How much complementarity exists between regions of high conservation value for genetic, species, and community diversity? How sensitive is the protection of biological diversity to the area protected? How much opportunity is there to protect biodiversity in disturbed landscapes? What is the economic value of various services we obtain from ecosystems and what is the economic value of biological diversity? How should we weigh instrumental with intrinsic values of diversity? How can planning tools be made to be more interactive and accessible to a broader cross-section of the public? Assessing Impacts and Managing Resources What species and communities occur in specific ecosystems and regions? What are their ecological requirements? How does the diversity of species influence various ecosystem services? What species play particularly important—keystone—roles in the system? How does fragmentation influence the key species? What methods can be used to successfully restore degraded habitats or ecosystem services? What are the long-term trends in the structure and function of given biological communities and what is the variability in various measures? What are the chronic effects of chemicals being released into the environment on plant and animal populations? How will species in various ecosystems respond to changes in temperature, precipitation, disturbance, and CO2 levels as predicted under climate models? What environmental indicators can be developed that bear on the achievement of environmental management goals? SOURCE: Walter Reid paper in Part II of this report. The International Geophysical Year (IGY) in 1957–1958, and the polar year in the late 1800s, are examples of special measurement efforts by scientists from many countries to establish a baseline understanding of the physical characteristics of the terrestrial and marine environments. The introduction of Dobson spectrophotometers and balloon-borne temperature sensors into several locations in Antarctica for the IGY and their maintenance since then have provided baseline data that allow scientists to know that the stratospheric ozone concentrations over Antarctica each October in the 1990s are very much less than was characteristic

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Linking Science and Technology to Society's Environmental Goals of the 1950s and 1960s. More recent efforts include the World Ocean Circulation Experiment and the Tropical Ocean Global Atmosphere Program, and the measurement of CO2 at the Moana Loa observatory in Hawaii. Comparable comprehensive global biological studies are still in the planning stages. One of the consequences of these varying stages of development is that people perceive the monitoring of physical characteristics differently from that of biological characteristics. Many physical characteristics have been or could have been recorded for two or more decades—stratospheric ozone concentrations have been measured almost daily over Arosa, Switzerland, since 1931, and comparable weather measurements have been made globally with calibrated instruments for many decades. But, the situation in the physical sciences is often that measurements have been made for an extended period, but for one reason or another the results are not comparable. However, even when such comparisons over time or space are an important focus of a research effort, the results are not useful for answering comparative questions. The causes of the failures are many, such as changes in personnel without adequate opportunity for transfer of precise protocol procedures, slow drift in equipment response or breakdown and repair without appropriate recalibration, relocation of equipment to a nonequivalent site, and change in time of day of measurement. Whatever the cause, the result is a seriously flawed time series of data. What would be necessary to conclude that an environmental goal was achieved, that measurable goals were to be consistently met? We need new metrics to define what a healthy environment is. —Forum Participant Comment The situation in the biological sciences is even more serious. First, biological systems are more complex and multidimensional than are physical systems. Although there are some standard descriptors of biological systems, such as species richness or population size and density, the fundamental decisions have yet to be made as to what characteristics are likely to be the most important for assessing whether a given change is an indicator of irremediable environmental degradation or loss of long-term ecosystem sustainability. Second, unlike the physical sciences, there are very few long-term data sets on biological factors in even the most prominent ecosystems, and those which do exist are either species-specific (e.g., the monitoring of deer populations on the George Reserve in Michigan) or geographically restricted (e.g., the monitoring of the wolf populations on Isle Royale) and are not designed to integrate multiple ecosystem functions. Finally, the data sets that do exist have many of the same flaws as the sets of physical data—such as changes in personnel, changes in protocols, failure to standardize collection methods among sites, and shifts in priorities at the collection site.

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Linking Science and Technology to Society's Environmental Goals The barriers to achieving America's most important environmental goals are primarily political. Over-costly approaches or methods that ask a subgroup of citizens to bear the costs for the whole country are naturally opposed. A cooperative spirit would be fostered if approaches were flexible and fair. Landowners who set aside habitat for endangered species should be rewarded, not penalized. Manufacturers who can find superior technology to prevent pollution should be allowed to do so, rather than following a fixed technology approach. Cities should be trusted to protect their citizens' drinking water. —Forum Participant Comment ECOLOGICAL KNOWLEDGE Of particular concern relative to gaining a better understanding of the state of the environment is ecology. Many of the environmental problems that challenge human society are fundamentally ecological. "Ecological knowledge and understanding are needed to detect and monitor changes, to evaluate consequences of a wide range of human activities, and to plan for the sustainable management of natural and human-dominated ecological systems" (Lubchenco et al. 1991). Scientific understanding of the structure and function of ecological systems and biodiversity has advanced tremendously over the last three decades. Still, the limits of scientific understanding of these phenomena are obvious: "Even where general trends, such as wildlife population declines or changing stream quality, are clear, scientists are often unable to determine the impact of a specific action on those trends with any precision (or even, whether the trends are a consequence of previous human actions or are natural). Problems of cumulative effects, lack of site-specific ecological knowledge, and the natural variability of ecological systems conspire to add substantial uncertainty to almost all uses of scientific knowledge in environmental decision-making. As a consequence, we must place as much emphasis today on techniques and policies for coping with uncertainty as we do with efforts to reduce that uncertainty" (see Reid paper in Part II). A recent National Research Council (NRC 1994a) report found such research to be rather poorly organized: "Many national and local agencies have responsibilities for understanding and managing the nation's biological resources, but there is no effective cross-institutional framework for identifying and conducting research of the highest priority, coordinating activities, or making information available in a coherent and usable way to the many agencies and other organizations that need The chief barrier to achieving environmental goals is ignorance—of how ecosystems interrelate, how to measure and observe systems, and how our society communicates and reaches consensus on specific actions to be accomplished. —Forum Participant Comment

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Linking Science and Technology to Society's Environmental Goals it.'' The absence of a national "organizational home" for ecological research hampers the integration of the results of research that is being conducted in various locations. Furthermore, such research is at a disadvantage in comparison with other research that has explicit "representation" in the federal budget process. Another NRC (1992c) report observed that the lack of an integrated national environmental-research plan, among other things, weakens the ability of the United States to work creatively with governments of other nations to solve regional and global problems. It recommended strengthening environmental research by fundamentally advancing factual knowledge, maintaining disciplinary research at the same time that emphasis on multiscale and multidisciplinary studies is increased, and ensuring economical and high-quality research with stable funding bases. Ecosystems exemplify an issue confronting society in many forms—complex, nonlinear dynamic systems. Better understanding of the functioning of natural systems might provide insights into how to interact with and control complex adaptive systems. Special attention should be given to developing new theoretical and practical approaches to characterizing natural systems in ways that improve our ability to manage them. MONITORING THE STATE OF THE ENVIRONMENT As concerns about the environment mount, an important role for science and technology is to provide quantitative data that characterize the state of the environment. In most human habitats, the ongoing state of the nearby supplies of air and water are of prime concern. Continuing efforts to monitor the purity of air and water are needed to determine qualitatively whether they are safe to breathe and to drink and quantitatively whether their purity is improving or getting worse. Such data are important not only as observations, but even more when decisions about the applications of economic resources toward such purity have been made or are under consideration. When steps have been authorized to produce a purer water supply, a proper role for science and technology is the quantitative determination of changes that have occurred in the water supply after implementation. Retrospective examinations of the efficacy of an improved purification procedure often reveal that some critical component has not been measured or the For the environment, science should be focused on providing clear and unambiguous data on the effects of pollutants on the health of people, other life forms, and the environment as a whole. It should also be attempting to clarify the areas where the data cannot yet be unambiguous, such as in global climate changes, and helping to protect realistically the possible scenarios, with best-estimate probabilities. —Forum Participant Comment

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Linking Science and Technology to Society's Environmental Goals instrument not calibrated after repair, etc.; the result is that the available data are inconclusive. The long-known solutions to this problem involve devoting a minor fraction of the effort to calibration, to testing of blanks and unknowns—in short, to continuing quality control of the data as they arise. Status of the U.S. Environmental-Monitoring System Currently, a great deal of monitoring data is collected in the United States. However, the data are incomplete, especially in ecology (because of the late recognition of the importance of ecological sciences), of varied quality, and nonstandardized in collection protocol (see Reid paper in Part II). Because of those problems, combining data from different regions and different times is unreliable. Currently, "the scientific community does not unanimously agree on what the best indicators of environmental quality should be" (see Reid paper in Part II). With standardization and sufficient quality control, some existing data sets could be more useful. "Federal, State, local and nongovernmental organizations (NGOs) spend hundreds of millions of dollars each year on the collection, storage and use of environmental data. Much of these data are collected for specific purposes and are not designed for developing general measures of environmental quality" (see Ross et al. paper in Part II). This brings up a number of questions as to how such data could be collected and used Can we make better use of existing nongovernment monitoring, such as that required as part of permit requirements under existing or future law? Can we make better use of data collected by a variety of government entities around the country? Can we make better use of the data collected for the many environmental-impact statements carried out throughout the country? Can we make better use of trained and supervised volunteers without compromising the quality of the data collected or the rights of private landowners. The U.S. Fundamental Ecological Research System The United States has no national program addressing fundamental ecological research, to provide coordination and focus. One way of meeting that need could be to establish a program of focused fundamental research under the auspices of a federal lead agency. Properly structured, such a program could provide the direction and momentum that are missing in the nation's ecological research. The research program could address fundamental research questions on a variety of scales, from cell to organism to ecosystem to region, as well as, for example, determinants of diversity, the role of fragmentation and edges, and the maintenance or restoration of ecosystem function. Although the details of the research program could be determined by the competitive process that has served research

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Linking Science and Technology to Society's Environmental Goals To conclude that our environmental goals were achieved, I would need scientific evidence that pollutants had diminished; that ecosystems were working; that there were no longer significant negative health effects from food, water, air, and soil; and that businesses and communities continued to function in a sustainable and successful manner consistent with ethical standards in a free and democratic society. —Forum Participant Comment in this country so well, the organization of research by problem would probably enhance effectiveness. One project, for example, could address fundamental biological and ecological questions at the same time that it provides information relevant to important human activities, such as agriculture, biotechnology, and manufacturing. The selection of the focus could engage scientists from the ecological research community in a systematic assessment of potentially productive strategic-program directions. We offer the following examples as illustrations of where current research needs to be expanded: Chemical and nutrient cycles. Determinants of natural and human-induced variation in natural populations. Physiological responses of organisms to natural and human-induced stresses. Habitat fragmentation, scale and edge phenomena. Maintenance and restoration of ecological services. Competitive-grant research programs could be organized to address such fundamental topics. At the same time, however, attention could be given to the practical aspects of the information being generated regarding such issues as deriving wealth from biological systems in sustainable ways, revealing the principal ways that human activities are stressing natural systems, and the ways such responses feed back to human society. The research could also improve the knowledge base for managing natural resources. INDICATORS OF THE STATE OF THE ENVIRONMENT Environmental indicators are a set of quantitative measures that provide a comprehensive picture of the condition of a nation's environment and that can be used to evaluate trends in environmental quality. Many agencies in the United States have begun attempts to develop such indicators. The agencies need to interact with the scientific community to review the indicators so that a consensus can be developed as to whether the indicators are sufficient or new ones are needed.

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Linking Science and Technology to Society's Environmental Goals There is not unanimous agreement among scientists or among countries as to what these indicators should be, but rates and direction of changes in environmental characteristics that lead to changes in biodiversity in a given region are certainly the framework by which the indicators should be assessed. The Ross et al. paper in Part II reviews how indicators are developed. The Organization for Economic Cooperation and Development uses the pressure-state-response (PSR) model.1 Environmental goals should include protection of natural resources, starting with clean air, water supply, and land. Environmental goals must be focused on maintaining or improving these vital resources. —Forum Participant Comment The process of measurement of the state of the environment begins with the selection of a set of appropriate indicators that are major factors in any marked changes or are closely bound in behavior to some factor. The protocol specifies how the appropriate data should be collected, analyzed, checked for quality, and stored for future access. Adequate provision must be built into the process for continual assurance that the measurement procedures and equipment are in standard working order. Finally, examinations of the data for consistency must be carried out periodically to determine whether unanticipated problems have entered into the picture. Because the preferred set of environmental indicators is likely to change over time, the nation's monitoring system needs to be of sufficient quality, content, and standardization to support a broad range of likely indicators. Data are needed not only for specific regulatory purposes, but also for developing general measures of environmental quality. FINDINGS, CONCLUSION, AND RECOMMENDATIONS Findings If the nation is to have useful environmental goals, indicators of progress toward these goals are needed. The quantification of these indicators must be based on monitoring data of sufficient quality and duration that relevant trends can be differentiated from noise. Reliable monitoring is also essential if the nation is to get early warning of emerging environmental problems (NRC 1991). The few long-term data sets that 1   The PSR model asserts that human activity exerts pressures (such as pollution emissions or land use changes) on the environment, which can produce changes in the state of the environment (such as changes in ambient pollutant concentrations, habitat diversity, and water flows). Society responds to changes in pressures or state with environmental and economic policies and programs intended to prevent, reduce, or mitigate pressures or environmental damage (see Ross et al. paper in Part II). Environmental quality is the reflection of the state component of the PSR model.

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Linking Science and Technology to Society's Environmental Goals exist have already played key roles in alerting humanity to impending serious problems (NRC 1992c). Current environmental data are being collected by disparate agencies and private groups. Much of this collecting is designed for other purposes (e.g., compliance) and not for developing general environmental indicators or providing early warning of environmental problems. The existing environmental-monitoring data sets on which environmental indicators and early warnings must be based are incomplete in space and time, especially with respect to ecology (because of the late recognition of the importance of ecological sciences), and are not necessarily relevant to measuring progress or anticipating problems. These data are also of varied quality and need better standardization (see Ross et al. paper in Part II). Managing the nation's environmental data is a complex task. In the NRC's (1994a) report on the National Biological Survey (NBS) titled A Biological Survey for the Nation, it was suggested that a distributed federation of databases be designed to make existing information more accessible and to establish mechanisms for efficient, coordinated collection and dissemination new information (NRC 1993). Far too much money is currently being wasted taking environmental data of dubious quality…in poorly chosen locations, and at temporal and spatial resolutions ill suited for comparison with the computer models used to…gauge progress. —Forum Participant Comment To establish indicators and identify emerging issues, only a small fraction of the data might be needed in some cases. The question is how we determine what fraction of data is necessary to support an indicators program. When evaluating such issues, it is important to take a hypothesis-driven approach and be responsive to clearly stated questions (NRC 1995d). Monitoring is not given adequate priority in the nation's science efforts (NRC 1992c). Although a number of reports have addressed the nation's monitoring system and made recommendations for its improvement, little improvement has been made (NRC 1991). The U.S. monitoring system is outdated and inadequate and would need to be modernized, expanded, and systematized to allow the calculation of useful indicators that match environmental goals. This monitoring system, which would provide the data for the indicators, should have sufficient quality control and standardization for the information yielded to be useful and the results from it to be believable. It could make possible the support of a compilation of indicators for a broad range of national and regional goals. This might allow for changes in goals and shifts in the choice of indicators. There are other reasons for wanting monitoring data beyond their use in measuring progress toward environmental goals: long-term monitoring data are of great use in basic science. Trends in such data can serve as an early warning of

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Linking Science and Technology to Society's Environmental Goals problems not yet recognized. For example, the long-term monitoring of CO2 data by Keeling has provided a key part of the information that scientists need to evaluate the potential for global warming. In addition, examinations of long-term data collections at natural-history museums has allowed scientists to show how plant life has responded in structure and form to changing atmospheric conditions. Currently, the scientific reward system tends to provide too little incentive for routine baseline data collection in relation to its potential value in giving early warning of possible environmental problems before they cause any appreciable harm. One example of a national environmental monitoring and reporting system for air quality is embodied in EPA's National Air Quality and Emissions Trends Report (EPA 1993). This report presents data on monitored concentrations of what EPA calls criteria air pollutants—PM10 (particulate matter), SO2 NO2 CO2 O3, and Lead—in the 30 largest metropolitan areas in the United States and estimates of aggregate emissions of the same pollutants. Although the report has limitations—for instance, it reports virtually no information on emissions or concentrations of hazardous air pollutants, such as benzene, acrylonitrile, and asbestos and does not measure concentrations in all parts of the country or within a given city—it is exemplary in several respects. For example, the reported trends are based on a relatively consistent set of ambient-air monitors, the data have been collected for a long period, the data are clearly summarized and presented (including measures of variability, in addition to nationwide averages), and the statistical findings are described in a clear and graphically attractive manner. The country would be fortunate to have comparable information on other environmental conditions and trends. For example, with respect to water quality, several monitoring systems would need to be taken into account. Creating a mission to support monitoring of environmental indicators and to provide early warning can bring needed focus to the nation's diffuse data-collection system. Conclusion Science and technology provide quantitative data to characterize the state of the environment. Scientists analyze and interpret this information to provide society with a deeper understanding of its relation to the state of the environment. As part of this analysis, they compare past conditions with projections to determine the potential for achieving a desired state of environmental quality at a feasible rate of change. One particular concern relative to achieving a desired state of environmental quality is our understanding of the ecological system in which plants, animals, and humans live. Current ecological data and understanding are inadequate to Detect, monitor, and characterize environmental changes. Evaluate the consequences of human activities.

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Linking Science and Technology to Society's Environmental Goals Provide an information base for sustainable management (i.e., "no loss") of both natural and ecological human-designed systems. Therefore, it is difficult to conduct the comparative analysis of past, current, and future ecological states (as described earlier) to determine what actions are needed to achieve a desired end of environmental quality. Furthermore, current programs do not address these issues in a sufficiently coherent and comprehensive manner on a national basis. Indicators that are needed to measure the current status of ecological systems, to gauge the likelihood of meeting society's environmental goals, or to anticipate problems resulting from economic growth are not available. We are spending much money to collect data that are neither complete nor always relevant to the decisions that society needs to make about land use, transportation, industrial activity, agriculture, and other human activities. The system of monitoring the state of the environment needs to be improved to make it more relevant to decision-makers, and there is need for a more-sophisticated and better-informed discussion of what needs to be measured and why. Recommendations The White House Office of Science and Technology Policy should review and evaluate the quality of existing measurement and monitoring systems for relevance to and usefulness in meeting environmental goals. That would include establishing a system-design process to complete and maintain the monitoring system. Congress should assign an existing or new federal research organization the mission of working with the scientific community to identify key subjects for ecological research and ensuring that this research is being pursued adequately somewhere in the overall environmental research system, which includes not only EPA and the Department of the Interior, but also the National Science Foundation, National Aeronautics and Space Administration, National Oceanic and Atmospheric Administration, Department of Defense, and DOE. Research should aim at identifying and developing reliable indicators of the health and sustainability of the environment and ecosystems. Such indicators might include chemical nutrient systems, habitat fragmentation, and changes in biodiversity. New systems of monitoring that meet society's decision-making needs should be identified and implemented. This includes provision of access to data sets via the Internet, integration of data from various scales (e.g., integrating satellite data with land-based measurements), and finding sources of historical data (e.g., glacial samples that have preserved the earth's history). The nation's existing monitoring system needs to be reviewed and evaluated for its relevance to indicators of environmental progress and identification of emerging issues. This evaluation procedure is a first step toward improving the overall system.

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Linking Science and Technology to Society's Environmental Goals For more information and guidance, the reader should refer to the following: NRC (National Research Council), Research to Protect, Restore, and Manage the Environment (Washington, D.C.: National Academy Press, 1993). NRC (National Research Council), A Biological Survey for the Nation (Washington, D.C.: National Academy Press, 1994). NRC (National Research Council), A Review of the Biomonitoring of Environmental Status and Trends Program: The Draft Detailed Plan (Washington, D.C.: National Academy Press, 1995). NRC (National Research Council), Review of EPA's Environmental Monitoring and Assessment Program: Overall Evaluation (Washington, D.C.: National Academy Press, 1995).

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