Chemical characteristics and temporal trends in eight streams of the Catskill Mountains, New York
Chemical characteristics and temporal trends in eight streams of the Catskill Mountains, New York
复制标题
纽约卡茨基尔山脉八条溪流的化学特征和时间趋势
DOI：
10.1007/bf00478154
复制
发表时间：
1993
期刊：
影响因子：
--
通讯作者：
J. Stoddard
中科院分区：
文献类型：
--
作者：
P. Murdoch;J. Stoddard
美国地质调查局（USGS）作为美国环境保护署（U.S. EPA）长期监测项目（1983-89）的一部分，对八条溪流的排放与浓度关系进行了研究，结果表明，大气沉积中的H2SO 4和HNO 3以及土壤中的有机酸会使一些溪流酸化。降水中主要离子的浓度与美国东北部其他地点报告的浓度相似。SO 42 −和NO3−的平均浓度在溪流之间是相似的，但碱阳离子浓度差异很大，这些差异导致了酸中和能力（ANC）的差异。在高流量下，基流ANC不是流酸度的可靠预测因子;一些具有高基流ANC（>150 M eq L−1）的流在高流量下下降至接近零ANC，并且一个具有低基流ANC（<50 M eq L−1）的流随着流量增加没有接近零ANC。峰值流量期间ANC和pH值的阶段性下降与NO3−和溶解有机碳（DOC）浓度的增加有关。在Neversink河和Rondout河的源头河流的高峰流量期间，观察到铝浓度超过300微克L− 1。时间趋势的季节性Kendall Tau检验表明，在1983-1989年期间，河水中SO 42 −浓度普遍下降，NO3−浓度上升。在整个记录期间，酸阴离子的总浓度（SO 42 −+ NO3−）基本上没有变化，这表明这些溪流的酸性沉积状态没有变化，而且NO3−正在逐渐取代SO 42 −成为卡茨基尔溪流中的主要酸阴离子。
Discharge to concentration relationships for eight streams studied by the U.S. Geological Survey (USGS) as part of the U.S. Environmental Protection Agency's (U.S. EPA) Long-Term Monitoring Project (1983–89) indicate acidification of some streams by H2SO4and HNO3in atmospheric deposition and by organic acids in soils. Concentrations of major ions in precipitation were similar to those reported at other sites in the northeastern United States. Average concentrations of SO42−and NO3−were similar among streams, but base cation concentrations differed widely, and these differences paralleled the differences in acid neutralizing capacity (ANC). Baseflow ANC is not a reliable predictor of stream acidity at high flow; some streams with high baseflow ANC (>150 Μeq L−1) declined to near zero ANC at high flow, and one stream with low baseflow ANC (<50 Μeq L−1) did not approach zero ANC as flow increased. Episodic decreases in ANC and pH during peak flows were associated with increased concentrations of NO3−and dissolved organic carbon (DOC). Aluminum concentrations exceeding 300 Μg L−1were observed during peak flows in headwater streams of the Neversink River and Rondout Creek. Seasonal Kendall Tau tests for temporal trends indicate that SO42−concentrations in streamwater generally decreased and NO3−concentrations increased during the period 1983–1989. Combined acid anion concentrations (SO42−+ NO3−) were generally unchanged throughout the period of record, indicating both that the status of these streams with respect to acidic deposition is unchanged, and that NO3−is gradually replacing SO42−as the dominant acid anion in the Catskill streams.