Comparison of macroinvertebrate communities of two intermittent streams with different disturbance histories in Letcher County, Kentucky
Small headwater streams receive little attention with regard to land management and regulatory policy, yet they greatly contribute to regional biodiversity and ecosystem function of their receiving streams. To ascertain differences associated with past logging and mining disturbances, I surveyed the macroinvertebrate communities of two first-order streams in the Eastern Coalfield Region (Letcher County, Kentucky) in spring, summer, fall, and winter 1998-1999. The reference stream drains old-growth forest in Lilley Cornett Woods; the disturbed stream lies in an adjacent hollow that was logged ca. 1940s and contour-mined ca. 1975. Benthic macroinvertebrates were collected using both quantitative and qualitative techniques at one site in each watershed. Results showed that the reference stream scored higher in measures of taxon richness, EPT richness, density, and diversity (H') but did not differ greatly in the pollution tolerance index (mHBI) or functional feeding group organization. Seasonal differences in taxon richness, EPT richness, density, and diversity within individual streams were noted and were attributed to life history phenologies of the resident taxa. Both streams had dominant taxa in common in spring (e.g. Paraleptophlebia, Epeorus), summer (e.g., Leuctra, Paraleptophlebia), fall (e.g., Diplectrona, Paraleptophlebia), and winter (e.g., Ephemerella, Epeorus), but wide variation in relative abundances were observed for most species. These results provide a reference for future comparisons of macroinvertebrate community structure in these and other small streams in the region.
Pond, G. J. 2000. Comparison of macroinvertebrate communities of two intermittent streams with different disturbance histories in Letcher County, Kentucky. Journal of the Kentucky Academy of Science 61:10-22.