COMPARATIVE WATER QUALITY OF LIGHTLY- AND MODERATELY-IMPACTED STREAMS IN THE SOUTHERN

Abstract

Abstract. For less-developed regions like the Blue Ridge Mountains. data are limited that link basin-scale land use with stream quality. 'lbo pairs of lightly-impacted (90-100 % forested) and moderately-impacted (7&80 % forested) sub-basins of the upper Little Tennessee River basin in the southern Blue Ridge were identified for comparison. The pairs contain physically similar stream reaches, chosen for the purpose of isolating forest conversion as a potential driver of any detected differences in water quality. Streams were sampled during baseflow conditions twice monthly over a six-month period from September 2003 through February 2004. Parametric t-tests were run for each parameter measured between the lightly-and moderately-impacted streams within each pair. Statistically significantly higher mean values of suspended and dissolved solids, nihate, specific condt~ctivity, turbidity, and temperature were observed in the moderately impacted streams versus the lightly impacted streams in both pairs, while dissolved oxygen levels were lower in the moderatelyimpacted streams. No significant differences were demonstrated in orthophosphate or ammonium coneenhution. A near-bankfull runoff event on February 6,2004. was sampled for stormflow values, and the results support baseflow findings. The water quality of these streams is very good when compared with lower relief areas like the Piedmont, and none of the parameters measured in thi