汤浦水库及入库支流水质时空变化特征与影响因素分析

运用聚类分析和主成分分析对汤浦水库及入库支流的水质时空特性进行了分析，聚类分析结果表明，汤浦水库水质可分为支流、支流入库库湾、水库库中3个典型空间区域和持续强降雨、雨季、非雨季3个季节时段。汤浦水库3个空间区域的主成分分析显示，第1、2主成分较好地反映了不同区域影响水质状态的主要因素。以水库库中为代表的水域水质明显不同于以北溪和南溪两条主要入库支流下游为代表和支流入库库湾两类区域，规律也不同，它主要受到随季节波动的库区初级生产力状况和无机盐的影响。汤浦水库3个典型季节的主成分分析显示，第1主成分较好地反映了不同季节影响水质状态的主要因素。以1至4月和9至12月非雨季为代表的水库水质变化与持续强降雨季节（6月）和降雨季节（5月、7月和8月）完全不同，主要受到气象因子和水位的双重影响，表现为营养水平波动、细菌等微生物的反硝化作用和水位涨落带的轻微有机及重金属污染。

Characteristics and Influencing Factors Analysis of Spatio Temporal Variations of Water Quality in Tangpu Reservoir and Its Tributaries

Cluster analysis and principle component analysis were used to analyze the spatial and temporal characteristics of water quality near and in Tangpu Reservoir. The results of cluster analysis showed that water quality of Tangpu Reservoir can be divided into 3 typical spatial areas including tributary, reservoir bay and reservoir, and 3 seasons including heavy rain, rain, and non-rain. Principle component analysis of 3 spatial areas in Tangpu Reservoir indicated that the 1st and 2nd principle components well reflect main factors influencing water quality of different area. Water quality in reservoir, which different from that in downstream of tributaries and reservoir bay, was mainly affected by primary production and inorganic salt fluctuated with seasons. Principle analysis of 3 seasons in Tangpu Reservoir indicated that the 1st principle component well reflects main factors influencing water quality of different seasons. Water quality in non-rain season (from January to April and from September to December), which different from that in heavy rain season (June) and rain season (March, July and August), was mainly affected by interact of and meteorological factors and water level, and result in fluctuations of trophic level, anti-nitrification by bacterial and microorganisms, and slight organic and heavy metal pollution in hydro-fluctuation belt.