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- Info
Restoration of aquatic ecosystems: Science, technology, and public policy
| Author: |
National Research Council; Commission on Geosciences, Environment, and Resources; Water Science and Technology Board; Committee on Restoration of Aquatic Ecosystems: Science, Technology, and Public Policy |
| Date: |
1992 |
| Periodical: |
Washington, DC: National Academy Press |
| Abstract: |
This report is the result of recognition by the Water Science and Technology Board of the National Research Council's (NRC) Commission on Geosciences, Environment, and Resources that it should be concerned with the emerging science of restoration ecology in relation to aquatic ecosystems. During its deliberations, the Committee on Restoration of Aquatic Ecosystems found that almost every restoration effort it reviewed focused on some component of a larger hydrologic system. The components fit into one of four categories: lakes, rivers, streams, and wetlands. However, the committee was also acutely aware that each of these entities functions in a larger ecological landscape greatly influenced by other components of the hydrologic cycle, including adjacent terrestrial systems. Regrettably, the case histories of restoration attempts that involved this larger ecological landscape were exceedingly rare. After much discussion, the committee finally decided to review restoration case studies in the components of lakes, river and streams, and wetlands because the available literature tended to be compartmentalized in this way and because it was a convenient and easily understood means of communicating a large body of information. At the same time, the committee believed very strongly that the spatial and temporal scope of most restoration efforts was far too small. Moreover, the committee felt that all too many environmental decisions, including those involving restoration, had been made in a fragmented fashion unlikely to produce a self-maintaining aquatic ecosystem integrated into the larger ecological landscape. As a result, there is a special chapter on integrated aquatic ecosystem restoration (Chapter 7) that discusses the failings of a fragmented approach and speculates on the advantages to be derived from a more integrated approach to restoring aquatic ecosystems. The committee recognized the difficulty of producing a report of acceptable length while also providing a useful level of detail on the large number of restoration efforts that have been completed or are in progress. It was decided that a limited number of illustrative case studies would be selected for review and that the level of detail would include only the information necessary to communicate the unique attributes of each restoration effort. This report describes the status and functions of surface water ecosystems; the effectiveness of aquatic restoration efforts; the technology associated with those efforts; and the research, policy, and institutional reorganization required to begin a national strategy for aquatic ecosystem restoration. Although ground water is an important natural resource in the United States and degradation of its quality has an effect on surface water supplies, the committee chose not to review restoration of ground water. Despite increasing awareness that some of the ground water in the United States is contaminated, public policy toward ground water protection is still in the formative stages. Increased technology and expanded monitoring activities probably will detect the effects of past contamination and land uses on water quality. Conclusive answers to questions about the location, extent, and severity of ground water contamination, and about trends in ground water quality, must await further collection and analysis of data from the nation's aquifers. The Water Science and Technology Board has in progress at this time a separate, special, detailed assessment of ground water remediation. The committee was much influenced by the strategy of the former NRC Committee on Applications of Ecological Theory to Environmental Problems. Our committee shares the 1986 NRC committee's perception that, whereas much about the functioning of ecological systems remains poorly understood, it is common to fail to use even available information when attempting to solve environmental problems. Finally, our committee also decided to provide examples of the creative use of ecological information, believing that a good example is more instructive than a bad one. In following this strategy, we also recognized that powerful analytical systems are not substitutes for biological insights or imaginative questioning and hypothesizing. Therefore, we joined the Committee on Applications of Ecological Theory to Environmental Problems in focusing on some important issues concerning restoration techniques. This report does not address the need for reintroducing species in restoration attempts, except to note the need for source pools of species in each ecoregion. The 1981 National Research Council report Testing for Effects of Chemicals on Ecosystems advocated the establishment of ecological preserves, although for a different purpose (test species for ecotoxicological procedures including the establishment of microcosms and mesocosms). The need for such ecological preserves as a source of recolonizing species will increase dramatically if the "no-net-loss" policy for wetlands and other aquatic ecosystems is not implemented expeditiously. The committee carried out its tasks through a series of meetings in which the format of the report was decided. Subgroups were formed to draft the various chapters. Restoration case studies were selected by these groups to illustrate points made in each chapter. The committee made four field trips to sites where restoration of aquatic systems had taken place or was going on. Subcommittees made two other site visits.
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