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An Exploratory Approach to Assessing the Influences of Environmental Factors on Fish Community Distribution and Health
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| Abstract: | The Chesapeake Bay is one of the most productive systems in the world. It supports a variety of aquatic resources of flora and fauna. However, for the past 350 years and especially in the last two to three decades, there has been substantial deterioration of the natural resources. Many species of submerged aquatic vegetation and benthic invertebrates have been extirpated. Commercial harvests of fish, crabs and shellfish have also declined. The cause of this ecological phenomenon is unknown, although it may be related to nutrient enrichment. To restore the Bay area and to conserve the fish resources, the causal relationships between the environmental stressors and the distribution and health of the fish communities must be understood. This research project adopts an integrated methodology involving the use of multi-variate ordination, statistical and geographical information systems (GIS) techniques to explore the intricate effects of various environmental factors on fish. Multi-variate ordination techniques are useful exploratory tools to help elucidate the latent environmental relationships and to define specific biocriteria. GIS is a spatial analytical technique for identifying spatial relationships. In this project, a non-metric multi-dimensional scaling ordination technique is employed in conjunction with other statistical techniques and ArcView GIS to reveal the relationships between a suite of environmental factors (including in-stream habitat characteristics and neighboring land use) and nitrate levels and fish conditions (such as the Index of Biological Integrity, % of abnormalities, the presence and absence values of fish species) in the riverine system. The results showed that land use is significantly related to nutrient loading, and each is related to the distribution and health of the fish communities. |
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| Citation: | Tong, S. Y., and S. M. Cormier. An Exploratory Approach to Assessing the Influences of Environmental Factors on Fish Community Distribution and Health. Presented at International Congress on Ecosystem Health: Managing for Ecosystem Health, Sacramento, CA, August 15-20, 1999. |
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| Contact: |
Linda Ransick - (513) 569-7395 or ransick.linda@epa.gov
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| Division: |
Ecological Exposure Research Division |
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| Branch: |
Ecosystems Research Branch |
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| Product Type: |
Abstrct/Oral |
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| Presented: |
08/15/1999 |
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