TESTING THE USEFULNESS OF QHEI GEOMORPHIC VARIABLES AND PROPORTION OF FINE SEDIMENTS AS PREDICTORS OF STREAM HEALTH: WESTERN ALLEGHENY PLATEAU

Many anthropogenic actions affect stream health, such as mining, development, and irrigation. The degree of impact on stream systems can be seen in changes to geomorphology, geochemistry, hydrology, and biology. Qualitative stream characteristics, such as those relating to geomorphology, can be quantified to measure stream health in the form of the QHEI (Qualitative Habitat Evaluation Index). The QHEI is an index of macrohabitat quality that relates stream potential to habitat quality on a macro-scale and measures emergent properties of habitat. The main focus for this study is use of QHEI to evaluate stream health in conjunction with geologic variables (geochemical and hydrologic) as predictors of stream habitat quality.

This study examines geomorphic variables that affect stream health (QHEI) relative to basal foodchain organisms present in streams of known adequate aquatic health in the Western Allegheny Plateau (WAP), Ohio. Algae are the basic source of energy for the stream ecosystem. Bedload is important to algae in that it controls exposure of the autochthonous primary production by controlling burial and affecting the turbidity of the water, which affects exposure to sunlight. Primary production of algae in relation to the trophic support can allow the diatom species metrics to be used as an indicator for the health of the rest of the ecosystem. The percent of fines in the bedload has been examined to determine how the fines affect algae. Biotic indicators are used as health gages. The bedload, diatom species metrics, and QHEI data are compared in an attempt to better understand how the fluvial geomorphology affects stream health.

This research project is a subset of the EPA STAR project in the Ohio Western Allegheny Plateau. The variables for this project include the biologic, geographic, and geologic variables with a specific focus on the geomorphology. The EPA STAR research group consists of subgroups of biologists, geographers, and geologists. The STAR project will study the geologic and biologic variables and the spatial relationships of the sampling sites to determine if there are any relationships that can be used to predict stressor levels in the absence of additional work.