4—
Resource Components

This chapter considers the various EMAP resources. In some cases, resources have been reviewed in earlier reports on surface waters, estuaries, and forests; for those, the executive summaries of the earlier reports are reproduced along with any new information. Brief, new reviews are provided here of the agroecosystem and Great Lakes. One of the program's originally planned resource groups, wetlands, has been eliminated, and insufficient information is available on the rangelands (formerly arid lands) resource group for review.

Agroecosystems

The activities of the Agroecosystems Resource Group of EMAP are reported in five documents: (1) Agroecosystem Research Plan, Heck et al., 1991a; (2) Agroecosystem Monitoring and Research Strategy, Heck et al., 1991b; (3) Agroecosystems 1992 Pilot Project Plan, Heck et al., 1992; (4) Agroecosystem Pilot Field Program - 1993, Campbell et al., 1993; and (5) Agroecosystem Pilot Field Program Report - 1992, Campbell et al., 1994. The monitoring phase of the Agroecosystem component of EMAP is scheduled to begin in 1998. To date the program has been largely concerned with research on biological indicators, establishment of relationships with the National Agricultural Sta-



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--> 4— Resource Components This chapter considers the various EMAP resources. In some cases, resources have been reviewed in earlier reports on surface waters, estuaries, and forests; for those, the executive summaries of the earlier reports are reproduced along with any new information. Brief, new reviews are provided here of the agroecosystem and Great Lakes. One of the program's originally planned resource groups, wetlands, has been eliminated, and insufficient information is available on the rangelands (formerly arid lands) resource group for review. Agroecosystems The activities of the Agroecosystems Resource Group of EMAP are reported in five documents: (1) Agroecosystem Research Plan, Heck et al., 1991a; (2) Agroecosystem Monitoring and Research Strategy, Heck et al., 1991b; (3) Agroecosystems 1992 Pilot Project Plan, Heck et al., 1992; (4) Agroecosystem Pilot Field Program - 1993, Campbell et al., 1993; and (5) Agroecosystem Pilot Field Program Report - 1992, Campbell et al., 1994. The monitoring phase of the Agroecosystem component of EMAP is scheduled to begin in 1998. To date the program has been largely concerned with research on biological indicators, establishment of relationships with the National Agricultural Sta-

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--> tistical Survey of the United States Department of Agriculture that will collaborate with EMAP and collect the majority of the field data, and refinement of the logistics of data generation from sample collection to data analysis and reporting. The objectives of the Agroecosystem component of EMAP are the same as those of the other resource components, i.e., the determination of the distribution and extent of agroecosystems, assessment of status and trends, association between changes in status and stressors, and preparation of periodic reports. While this consistency is necessary and appropriate, the application of the EMAP approach and protocol to highly managed agricultural ecosystems is problematic. Nearly all past agricultural research has focused on management of agricultural commodities. Practically nothing is known about the other biological components of agroecosystems. Gathering such information is problematic as the intensive management of agroecosystems can overwhelm measures that would be meaningful in other ecosystems. For example, the application of nitrogen fertilizer causes extreme short-term changes in soil chemistry and microbial community structure and metabolism. It is difficult to avoid these effects completely in a sampling protocol because nitrogen fertilization practices vary with crop, agroclimatic zone and individual farmers. Development of meaningful indicators that are relatively free of influence by agricultural managers is an extraordinary challenge, but it is necessary given the frequency of sample collection. The strategy of the Agroecosystem component involves monitoring of indicators that are clustered around three assessment questions and collection of samples and data by the National Agricultural Statistical Survey. The assessment questions are expressed differently in several of the documents produced by the resource group but are reasonably consistent in intent. They include: sustainability of production potential for commodities; quality of air, water and soil; and maintenance of biological diversity.

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--> A fourth and implied assessment question involves the impact of agroecosystems and their management on adjacent and downstream ecosystems. These assessment questions seem appropriate and comprehensive. However, the development of quantifiable indicators for such questions is difficult. The measurement of physical and chemical properties of air, water, and soil and the identification of trends in such measurements are straightforward. However, integration of these properties into a measure of quality and establishment of acceptable levels of quality is far from straightforward. The assessment of the sustainability of production potential is limited by the current state of the art to monitoring of crop yields. The relationship of yield to ecosystem condition is unclear. During the past decade, yields of wheat and rice agroecosystems in southern Asia have declined. Whether or not this decline represents a compromise of the sustainability of production is as yet undetermined, despite considerable research efforts to identify the cause of such declines. EMAP's attempts to assess the value of production efficiency as a measure of sustainability are admirable, but they are still in the research stage. Because yield data are already available, EMAP's greatest contribution to monitoring agroecosystems is the development of indicators of overall ecosystem status. Appropriate indicators of biodiversity within agroecosystems are not yet perfected. EMAP's exploration of the potential of using trophic groups of nematodes as indicators of soil health and diversity is founded on good theoretical grounds, but experimental testing of the theory is still under way. The recent addition of hedgerows and pest-management parameters will expand the number of habitats sampled, and thereby likely improve overall estimates of system diversity. The challenge for EMAP is to ascertain the set of taxonomic divisions and habitats that will reflect the system diversity. Because of the regional variability in the nature and distribution of agroecosystems, EMAP should test the adequacy of the sampling grid. In the Southeast and Midwest, agroecosystems are relatively uniform in distribution because the landscape is

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--> relatively uniform, and rainfall is generally adequate for growing crops. The base grid will likely sample such regions very well. In the arid regions of the West, and especially in central California, agroecosystem distribution is very patchy because agroecosystems are clumped around sources of irrigation water. High-volume crops such as fruits and vegetables are generally grown in these areas with high yield and economic return. In the Northeast, agroecosystems are typically patchy because of the topography. Agroecosystems with patchy distribution are less likely to be sampled adequately by the base grid. EMAP intends to collaborate with the National Agricultural Statistical Survey in the collection of data. Essentially, EMAP will augment the sampling grid and data requirements of the survey, which has been ongoing for years. The partnership will capitalize on the experience and expertise of the United States Department of Agriculture while contributing the ecological experience and perspective of EPA and EMAP. The ecosystem components that are not commodities and the influences of agroecosystems on adjacent and downstream ecosystems are concerns that EMAP will add to the survey. EMAP should be commended for forging this partnership to increase the utility and cost-effectiveness of the efforts of both agencies. The 1992 pilot program of the EMAP Agroecosystem group was conducted in North Carolina by a new partnership between EMAP and the Department of Agriculture National Agricultural Statistical Service (NASS). This partnership represents an attempt to modify the NASS survey of U.S. agricultural lands to be compatible with the sampling and data needs of EMAP. The pilot was conducted as the first attempt to perform field operations, collect and prepare samples and field data, transport samples to various laboratories for analysis, and to manage and analyze resulting data. In essence it was a true operational pilot study. In most respects the pilot was a qualified success. Data-collection was incomplete for several reasons, including failures by the National Agricultural Statistical Service (NASS) to adequately

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--> adapt, and problems in quality control. None of these failures is surprising in a first trial. However, it is essential to resolve these issues before implementing the EMAP monitoring program across a greater area. The pilot failed to establish the suitability of its indices and measures as indicators of ecological condition. While some of the indices and measures have potential, their values are not yet documented. The report of the pilot recognized its limitations and failures, but few details were offered about correcting the deficiencies in future activities. It is unlikely that the lessons of the 1992 pilot were used to modify the 1993 pilot, as the report of the 1992 study was published in 1994, well after the second pilot was completed. The Pilot Field Program of 1993 was conducted in Nebraska. It had four major objectives as follows: (1) empirically establish the range and variance in indicator values within the State of Nebraska; (2) to compare the efficiency and precision of the EMAP hexagonal design and the NASS rotational panel design; (3) refine plans for logistics and data handling; and (4) develop and evaluate additional indicators of soil quality and landscape structure. Also included within the first objective was a subobjective to assess the ability of indicators to reflect condition. These are generally worthwhile objectives, and the plans for implementing them seem sound. Only the subobjective of assessing the ability of an indicator to reflect ecosystem condition seems questionable. The establishment of the correlation between indicators and ecosystem condition is a great challenge faced by EMAP across all resource groups. It is particularly challenging to the Agroecosystem group because there is so little ecological knowledge available on agroecosystems. The challenge will only be met by persistent research and empirical evaluation of indicators.

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--> Conclusion The Agroecosystem resource group is subject to most of the same concerns that have been expressed about other resource groups. The utility of indicators, especially the biological indicators, is largely undocumented and requires empirical research over several years to provide such documentation. The intensity of the base grid may be too coarse to adequately sample adequately agroecosystems that have patchy distributions. Questions concerning data management, coordination with other resource groups, and interagency cooperation are virtually identical to those in other resource groups. Most problematic is the appropriateness of the EMAP approach, primarily intended for natural systems, for monitoring intensively managed agroecosystems. The Agroecosystem program is at an immature stage of development relative to other resource programs. This is not surprising as the focus of past agricultural research has been on management of a few species and particularly on factors affecting their yields. Ecological sustainability, and its relationship to biotic components, and the functional linkages among such components are relatively new concerns for to agricultural scientists. Efforts are under way at several institutions to develop methods for assessing agricultural sustainability. EMAP would be well served to become familiar with such efforts and to incorporate them in its deliberations and plans. Examples include the Sustainable Agriculture Research and Extension-Agriculture Compatible with Environment (SARE-ACE) and Sustainable Agriculture and Natural Resource Management (SANREM) programs at the University of Georgia, work at the Leopold Center of lowa State University, and the Agroecology program at the University of California at Santa Cruz.

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--> Estuaries (Modified from NRC, 1994a, Executive Summary) The goals of the 1990 Virginian Province demonstration project were to identify which indicators and design attributes are most effective for assessing the ecological condition of estuarine resources on a regional scale with limited financial resources. Significant progress was made in many areas. The grid-sampling scheme was successfully modified to represent better discrete systems such as small estuaries and large rivers without compromising the acquisition of unbiased samples. A complex field-sampling program was successfully mounted with a well-coordinated plan for quality assurance of data acquisition, analysis, and management. Initial steps were taken toward the development of a group of indicators of ecological condition. Subsequent efforts have been made to involve regional managers by having them cooperate in future sampling and in the evaluation of the applicability of data collected. The activities and results of the first year of sampling (1990) have been issued in a well-written synthesis report describing the process of indicator development and containing an initial interpretation of the data obtained (Weisberg, et al., 1992). Based on the material in this report, EMAP has made a good first step in getting the estuaries section of EMAP started. Although there have been many positive accomplishments, there are a number of areas needing significant work. A more explicit conceptual model must be developed to drive indicator development and set priorities. Continued work also is needed to develop meaningful indicators that assess basic ecological condition (status and functioning). The combination of the EMAP probability-based sampling design and the realities of national coverage with a limited budget severely limit the type and number of indicator measurements that can be made. The review panel of the Estuarine Research Federation doubts that the indices generated by EMAP will have the power to detect the amount of environmental change expect-

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--> ed. Environmental change can occur at various rates. For example, the EMAP design standard is the ability to detect a 20 percent change occurring over a decade. The published information on changes in various indicators shows, however, that some changes occur in estuaries at a much slower rate than this (Stanley, 1993). As a result, it may take several decades for a 20 percent change to occur, therefore, it would take decades to be able to detect changes with the current EMAP sampling design. By contrast, changes in ecosystems can be quite sudden and catastrophic, perhaps too fast to be adequately captured by EMAP's sampling scheme. It is time for this issue to be clearly analyzed by EMAP using extant data sets or similar proxy data. According to the letter from Dr. Martinko (Appendix A), these studies are currently being carried out on Virginian Province data sets. Future (1995-1996) analyses are planned on existing data sets from the Louisianian Province. Large programs such as the estuaries component of EMAP usually pay insufficient attention to analyzing exactly what they have learned in their pilot and demonstration projects. There is a temptation to think that the next challenge is to carry out pilot projects on new provinces, one after another. However, as pointed out by the Estuarine Research Federation review committee, the real challenge is in obtaining the best possible set of indicators of ecological condition. Therefore, EMAP personnel should stop and evaluate the estuaries part of EMAP in detail before going on or adding additional provinces. This evaluation should occur as soon as possible after the Virginian Province demonstration completes its first four-year cycle and should include a comparison of the EMAP information with other published information on indicators of condition of estuarine resources with different design attributes. This evaluation has begun (See Appendix A).

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--> Indicators The estuaries component of EMAP should include indicators of ecosystem function. These indicators are difficult to monitor when studies are made only once a year, but can be estimated to some extent indirectly. Lack of such indicators should be addressed as soon as possible. An example of such an indirect approach is that algal biomass can be used as a surrogate for primary production. Also, remote sensing provides one possibility for chlorophyll measurements on a regional scale. Another measure of important coastal habitat, submerged aquatic vegetation, was missing in the Virginian Province demonstration project. Inclusion of submerged aquatic vegetation in the sampling scheme for all estuaries demonstration projects should be considered. Insufficient effort has been devoted to fish sampling to make the data obtained useful. A relatively short trawl done once does not collect enough fish for meaningful determination of population characteristics, contaminant body burdens, or incidence of gross pathology. If quantitative information on these indices is desirable, arrangements should be made with other agencies with the experience and personnel on hand for more comprehensive collection and analysis of data. If the level of planning and effort allocated by EMAP for these activities cannot be significantly increased, fish sampling program should be eliminated. In support of new indicators development, areas of research that should be looked at include the analysis of long-term data sets from various sites to examine indicator variability and its causes and the use of molecular probes to look for the presence of enzymes indicating pollutant exposure or changes in ecosystem function (e.g., nitrogen fixation). No use has yet been made of a number of historical data sets in the Virginian Province that have data comparable to those being collected by EMAP. Out of 18 studies investigated, eight were found to contain information important to EMAP and in

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--> particular to EMAP-Estuaries. This material should be analyzed in detail to provide valuable information on spatial and temporal variability and the power of certain indicators to detect trends within a given period. It is past time for this work to have been completed. (This recommendation is addressed in Appendix A. Advice, Consultation, and Scientific Review EPA has sought advice from a wide variety of scientists in developing EMAP, but the effectiveness of the present mechanisms for incorporating scientific expertise into the design and execution of resource group activities are not what they should be. Working groups, which have been used by most of the resource groups, provide peer review but are not necessarily efficient or adequate for ensuring that activities are based on the best scientific approach. Continuing oversight and review by groups of scientists from outside of EPA, built into the program at the highest levels, should be implemented for EMAP Center planning, for indicator development strategy, for landscape characterization, and for all resource groups. Update There has been progress since the last report dealing with estuaries was written. Some of the progress has been responsive to the report. Much of the recent progress in the development of indicators and sampling methods has not yet appeared in documents available for review, and so the following evaluation of progress may not be complete. Two big issues face EMAP-Estuaries (and the other resource components)—indicator development, and the time and space scales at which interpretation of the measurements will be meaningful. EMAP-Estuaries appears to have made some progress with respect to indicators, but the information available does not

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--> indicate whether the program will be able to adequately assess trends in the condition of the nation's estuaries. Indicators EMAP officials report that a revised conceptual model for indicator development will be released later in 1994. It should be based on ecological relationships and on how disturbances of the ecosystem would be reflected in the various indicators to be measured. For instance, excess nutrients would lead to hypoxia that could be measured by increases in the extent of areas with low dissolved oxygen. Thus far, it is not clear from EMAP's response to the previous report, which called for explicit conceptual models, that this is the type of model being developed. Detecting Trends The fish-sampling program is fundamentally flawed. It is not clear how a supportable program could be undertaken without a large increase in investment of resources for adequate development of indicators. The type of extensive sampling that supported the development of an approach for measuring dissolved oxygen would have to support the development of any indicator based on measurements of fish collected. It is still not clear that the EMAP sampling design and indicators will have the power to detect the kinds of environmental changes anticipated at the appropriate scales. This is because of the high degree of spatial and temporal variability in estuarine systems and because rates of change are expected to be slow. Stanley (1993) was forced to lump data into 10-year increments and into three major river sectors to detect change, even with monthly sampling at many sites for more than a decade. EMAP is primarily concerned with changes in the areal extent of indicator distributions. However, based on the known spatial and tem-

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--> also because those goals and questions are a very incomplete list of the fundamental issues that need to be addressed before the surface waters program is ready for full implementation. In particular, issues of coordination among resource groups, relationships between indicators and specific stressors, and ability to make inferences on scales ranging from single lakes to entire regions were not addressed. Not every issue can be addressed in a single pilot study, but there appears to be no overall plan to address these issues sequentially in subsequent pilot studies. In addition, oversight and involvement of senior scientists from a central management team at EMAP Center might have enhanced the scientific rigor of the pilot study, improved the design, analysis and reporting phases of the pilot study, and produced more useful models for the full program. Background and Objectives The Surface Waters component of EMAP has responsibility for achieving EMAP goals for the nation's lakes, reservoirs, streams, and rivers. Surface Waters is one of eight EMAP resource groups. The other resource groups are: forests, estuaries, agroecosystems, arid lands, the Great Lakes, wetlands, and landscape ecology. EMAP-Surface Waters' initial efforts emphasized lakes and reservoirs, and this portion of the program is more fully developed than the program for rivers and streams. For lakes and reservoirs a pilot project was conducted from 1991 to 1993 in the northeast area of the United States. A stream pilot project was conducted in the mid-Appalachian area in 1993. EMAP-Surface Waters differs from most other surface water monitoring approaches in that it is statistically designed to infer information from a sample of lakes to the entire population of lakes on regional and national scales. Objectives of EMAP-Surface Waters parallel those of the general EMAP program. The objectives of the Surface Waters Component (from D. McKenzie, EMAP Program Officer, verbal communication, February 24, 1994) are to:

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--> estimate the current status, trends, and changes in selected indicators of condition of the nation's lakes, reservoirs, streams, and rivers on a regional basis with known confidence; estimate the extent (number and surface area of lakes and reservoirs, miles of rivers and streams) of the nation's lakes, reservoirs, streams and rivers with known confidence; seek associations between selected indicators of natural and anthropogenic stresses and indicators of the condition of ecological resources; and provide annual statistical summaries and periodic assessments on the condition of the nation's lakes, reservoirs, streams and rivers. Assessment End Points EMAP-Surface Waters has designated three assessment end points for the lakes portion of their program: biological integrity; trophic condition; fishability. The choice of assessment end points provides the foundation for the EMAP Lakes Program. This first step, therefore, is of critical importance. The EMAP-Surface Waters' current selection of end points needs further definition and improvement. Of the three end points, biological integrity is the most problematic. As used by EMAP-Surface Waters, this term is vague and all-inclusive, conceptually subsuming the content of the other end points and all other more specific environmental problems in lakes. Such a broadly defined term may be useful in summarizing diverse data or in addressing the multiple issues related to environmental quality, but it is not specific enough to be a useful end point upon which to design data monitoring activities. Therefore, EMAP-Surface Waters (and other EMAP resource groups) should use the term "appropriate biological diversity" instead of "biological integrity" as an assessment end point, as discussed in Chapter 2. This term is based on objective evaluations and depends on measurable, quantifiable reference systems, and its use should lead to the development of objective, quantifiable indicators. The other two assessment end points for EMAP-Surface Waters are trophic condition and fishability. In theory, each could be

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--> defined in reasonably unambiguous ways and straightforward means can be developed to measure them quantitatively. Nonetheless, further efforts are needed to refine the definitions and measurement strategies for both end points. In addition, although EMAP's financial resources will be limited, it is imprudent to exclude drinking water from consideration as a societal value in its surface water assessment program. The EPA and the revised Clean Water Act both express and affirm the concept of holistic watershed planning and management. Also many impoundments and natural lakes are used both for recreation and for drinking water supplies. This is an example where close cooperation with EPA's Office of Water 305b program could be very beneficial. Indicators Once the major assessment end points have been decided, the next critical task is to determine what measurements are necessary to assess these end points. When the problem has been stated, a conceptual model of how the particular system works with respect to the problem should then be stated explicitly. Examination of the conceptual model leads to the selection of potential indicators, which are tested in the field. The indicators are selected on the basis of known or suspected cause-effect relationships that are identified in the conceptual model. Until March 1994, EMAP provided no satisfactory program-wide guidelines for indicator selection strategy, and each resource group was left to fend for itself with little or no guidance from EMAP-Center. As a result, use of conceptual models to drive indicator selection is not well developed in EMAP. The conceptual model implicit in the EMAP-Surface Waters strategy document underestimates the complexity of freshwater ecosystems. There is no consideration of factors like biogeography, seasonal shifts in community structure with secondary nutrient depletion, competition, predation, or hydrologic factors.

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--> Therefore, explicit conceptual models of the ecological systems being monitored should be used to guide indicator development. EPA's peer review panel was concerned about heavy reliance on indices with unknown properties. Use of indices to describe complex ecosystems has some advantages but also some important disadvantages. The major advantage is the ability of an index to condense many parameters into a single number, which at first glance may be easier to understand. A major disadvantage is that the statistical properties of the index are often not well understood; moreover the indices are often nonlinear; that is, a change from 1 to 2 is not the same as a change from 2 to 3. Rather than relying upon a univariate index with unknown statistical properties, it is possible to use the multi-response vector of the original parameters and apply multivariate statistical techniques for analysis (e.g., logistic regression, clustering and pattern-recognition algorithms, neural network analysis), or exploratory data techniques involving better visualization of multi-dimensional data (Becker et al. 1987, Cleveland and McGill 1988). Nonparametric multivariate procedures also exist (as in Zimmerman et al. 1985) for testing whether groups of multivariate data points are significantly different from each other (e.g. comparing disturbed to undisturbed areas). EMAP-Surface Waters should continue its efforts to develop indices using a number of different approaches including multivariate statistical and exploratory data analyses. In addition, appropriate new statistical methods should be incorporated as they become available. Sampling Design The design for the Surface Waters component follows the overall EMAP design. The scheme for lakes is better developed than that for streams, which have not received detailed consideration to date. About 3,200 lakes will be selected using a probability-based sampling scheme. A different subset of 800 of them will be sampled each year so that every lake is sampled once every four-years. Lakes will be stratified into size classes so that large lakes (which are relatively rare compared to small lakes) are represented in the sample. The random selection of the lakes will

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--> occur in a way that maintains uniform spatial coverage nationally. There are several areas of concern regarding the general EMAP sampling design. A watershed perspective is lacking in the sampling design. Because surface water systems are linked with their watersheds, the lack of a watershed perspective will severely limit the identification of likely causes of detected changes in the EMAP lakes. Without this watershed perspective, landscape characterization data cannot be used to evaluate the status of individual aquatic resource units. Thus, a greater emphasis should be given to concomitant measures of watershed characteristics. Remotely sensed data on land use and cover could be used to great advantage. Representatives of EMAP have recently indicated (May 1994, conference call with surface water panel members) that they will be using a watershed approach for their data gathering, and the committee encourages this approach. Another concern is that the sampling design may not be sensitive enough to detect a change in condition unless the change is very large in magnitude and affects most lakes and streams in a region. There are many types of lakes and streams in many types of landscapes and each one has different sensitivities to a particular stress. It is not clear that enough sensitive lakes and streams will be included in the sample to detect a change due to a particular stress. Because lakes and streams will be sampled during one 9-week period, some measurements may not be made at the biologically most meaningful time, thus decreasing the sensitivity of the measurement. In addition, the sampling design may have difficulty detecting changes in biological measurements over time. Variances of biological populations (and therefore community measurements) among lakes and within lakes over the course of a year are large. EMAP-Surface Waters has been a leader in performing tests of statistical power to detect changes or differences with real limnological data collected by various state agencies. Power studies to date have examined primarily physical and chemical variables since these data were relatively available. Similar tests with published or simulated biological (population and community

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--> level) data should be vigorously pursued, because EPA indicates that these data will be important in formulating indicators similar to Karr's Index of Biological Integrity (Karr, 1992). It is not clear how useful the trends that EMAP may detect will be, and whether EMAP will be able to relate such trends to specific stressors is uncertain. Because of the four-year revisitation rate, the current design essentially does not allow for site-specific inferences to be made. Although it is not an explicit goal of EMAP to make site-specific inferences, there is value in making site-specific inferences from well-chosen sites. This would augment the basic EMAP design and the added value could be achieved at small additional cost. Therefore, a substantial number of sites should be sampled annually. Some of these sites might be selected because they are known or suspected to be sensitive indicator lakes for selected stressors. Additional power tests should be performed to examine the ability of the current design to detect status and trends for quantiles in the tails of distributions (e.g., lower and upper 10th percentiles). Lake Pilot Project The surface water component of EMAP began its first year pilot study during the summer of 1991. Pilot activities included a regional sampling effort (EPA Region 1), a set of more focused indicator development studies, and an analysis of the effects of different types and magnitudes of variability on the ability to detect regional trends. The regional assessment portion of the pilot study represents the first application of the general EMAP design to surface water ecosystems. The EMAP-Surface Waters implementation pilot was reasonably organized, and logistical aspects of the operation were well planned. Field execution of the regional assessment portion of the pilot was successful. Valuable experience was gained in the site selection process and in evaluating the logistical aspects of the program. However, a substantial portion of the data was not analyzed in time to meet deadlines for the pilot study report. This

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--> suggests that a larger investment in data analysis will be necessary if a larger scale implementation is to be completed in a timely fashion. The design of the indicator development study was not as good as that of the regional assessment portion of the pilot. The scope of this portion of the pilot was too ambitious given the financial resources available. The response of lakes to catchment disturbance, or even the ability of certain indicators to detect the response, is unlikely to be discerned without a much larger set of lakes selected specifically to address this question. With only four to six lakes per class it was unreasonable to expect to be able to see a strong signal between disturbance and the response variables. Field sampling for the indicator portion of the pilot appeared to go smoothly. Useful variance estimates and time and cost estimates were obtained for many of the assemblage indicators. However, there appear to be major difficulties with the analyses of the indicator assemblage data. They include: lack of planning and coordination; lack of statistically sound hypothesis evaluation; and lack of any quantitative comparison between the various indicator variables measured. Streams EMAP-Surface Waters also began to conduct a pilot program on streams in the summer of 1993. It is difficult to evaluate this pilot study, because of the scarcity of documentation. The sampling strategy to be used in the stream survey needs further development. Based on the limited information now available, it was premature to embark on a stream pilot study at this time. The currently conceived sampling strategy appears inadequate to characterize stream quality either chemically or biologically. Not everything can be planned in advance, and there still is room for the trial-and-error approach in developing large-scale

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--> programs like EMAP. Nonetheless, the scale of financial and human resources required even for a pilot-level survey is sufficiently great that EPA must not only minimize the risk of error, but also maximize the likelihood that it will successfully address the critical issues necessary for planning a full-scale stream survey. EMAP is not presently in this position. EMAP should decide what its overall objectives are for assessing the status of the nation's rivers and streams. These objectives—and a strategy to achieve them—need to be developed within the context of existing federal monitoring programs. This should occur before EMAP proceeds with the development of stream pilot studies. The currently conceived sampling strategy is not appropriate to characterize stream quality either chemically or biologically. It is unclear to what extent there has been substantive involvement of the scientific community in the planning done to date for the streams pilot. Therefore, EMAP-Surface Waters' scientists should spend time developing a substantive planning document and continue their dialogue with stream scientists in other branches of EPA, in other water-related federal agencies (U.S. Geological Survey, U.S. Fish and Wildlife Service, etc.) and in the academic community to better evaluate how the stream phase of EMAP should be designed. Intra-Agency Cooperation Much routine water quality sampling done by state pollution control agencies on surface waters nationwide is funded through EPA's Office of Water under Section 305b of the Clean Water Act. Closer collaboration between the 305b program and EMAP has the potential to enhance the effectiveness of both programs while reducing the overall cost of federal monitoring programs for surface water quality. Therefore, EMAP-Surface Waters and the EPA Office of Water should work together to insure that data collected under the 305b program can be useful not just for compliance monitoring (the primary focus of current programs in most states), but also to assess temporal and geographic trends in water quality.

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--> Oversight And Coordination Among EMAP Resource Groups Coordination among resource groups is especially important for the Surface Waters component of EMAP. Surface waters are affected by processes occurring within the terrestrial ecosystems in their watersheds. Currently, the Surface Waters group is analyzing riparian vegetation. However, it is not clear that the classification system being used is the same as that used by terrestrially-focused resource groups. Without a closer interaction with the terrestrial components of EMAP, an opportunity for comprehensive understanding of how and why lakes may be changing is likely to be missed. EMAP-Center Organization There is a continuing lack of a clearly defined procedure for defining and prioritizing the assessment questions that can and will be addressed by the program. These questions are critically important, because they will drive the sampling strategies and clarify the goals of EMAP-Surface Waters and the other resource groups. A procedure should be developed to identify the most important assessment questions from a policy perspective, but at the same time ensure that it is scientifically feasible to address the questions. One possible approach is to formalize a planning structure that would be composed of guidance panels associated with each resource group. A central planning committee, composed of representatives from each of the thematic panels would then make the hard decisions about resource allocation and attempt to optimize efficiency and coordination between groups. Some aspects of such a planning structure already exist within EMAP. However, it is critical that the guidance panels also include representatives of EMAP clients, i.e., policy makers and the larger scientific community. Most panel members should be external to EMAP and to EPA and they should be leaders in their areas of

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--> expertise. These panels should not duplicate the advisory and planning functions of the current peer review panels or of EPA's Science Advisory Board.

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