PERIPHYTON ASSEMBLAGES AS BIOINDICATORS OF MINE-DRAINAGE IN UNGLACIATED WESTERN ALLEGHENY PLATEAU LOTIC SYSTEMS

摘要

In order to determine the influence of geologic patterns and coal mining on benthic algal assemblages, 56 stream sites throughout the unglaciated Western Allegany Plateau were investigated. These sites were categorized based upon catchment mining/reclamation history. At each site, select environmental parameters such as pH, temperature, dissolved oxygen, specific conductance, metallic salts concentration, turbidity, maximum wetted width, and average thalweg depth were measured. Periphyton from riffle areas and macroscopic algal taxa from a 20 m segment were collected. Relative importance values were developed and calculated for both the periphyton and macroalgal communities. Canonical correspondence analyses of the periphyton and macroalgal data set each showed five major groups of stream reaches that were defined by specific algal taxa and environmental characteristics. Two of the groups were dominated by variables associated with acid mine drainage (AMD) and had taxa known from very acidic waters. One group was entirely composed of sites receiving treated waters from active coal mines. Another group was dominated by sites classified as alkaline mine drainage (AkMD) and the last group was primarily reference sites with a few reclaimed reaches. The AMD impacted groups had a significantly lower species richness and diversity than the other three groups. Species-based models for inferring the level of critical environmental parameters related to mining showed the periphyton-based inference model for pH was highly predictable and may be quite useful for evaluation of coal mine remediation. Other promising periphyton- and macroalgal-based models, yielded poor r~2 and root mean square error (RMSE) after cross-validation. Comparison of the relative importance values with more traditional assessments of community structure showed similar results with the diatoms and chlorophytes dominating the periphyton and macroalgae, respectively.