Relationships Between Upstream Land Use at Multiple Spatial Scales and Benthic Macroinvertebrate Community Composition in the Deerfield River Watershed of Vermont and Massachusetts

Download or read book Relationships Between Upstream Land Use at Multiple Spatial Scales and Benthic Macroinvertebrate Community Composition in the Deerfield River Watershed of Vermont and Massachusetts written by Jason Saltman and published by . This book was released on 2009 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, I examined relationships between land-use patterns and macroinvertebrate communities in 45 first through fourth-order stream reaches in four subwatersheds within a New England watershed. Land-use patterns were quantified in GIS at three spatial scales to determine the effect of scale on the strength of relationships between instream biological conditions and adjacent land-use conditions. A GIS was used to quantify forest, agricultural, and developed land use at three spatial scales, including the entire upstream catchment area and two sub-corridors. Macroinvertebrate communities were analyzed using a multimetric approach and a multivariate approach to relate community composition to land-use variables measured at each spatial scale. Among community metrics, richness, EPT richness, percent affinity, and total metric scores were significantly correlated with quantified land-use variables, including percent forest, percent agriculture, percent developed, and percent agriculture + developed at the upstream catchment scale. Land-use variables also showed significant correlations with community composition as indicated by ordination axes resulting from multivariate analysis. Results of the approaches were in general agreement with each other, each indicating that relationships between instream benthic conditions and adjacent land use were strongest at the entire-upstream-catchment scale. These results suggest that conditions and processes occurring at this scale appear to be more influential than are localized adjacent land-use conditions in shaping community composition and in-stream biological conditions.