Spatial-temporal characteristic of water quality in Lake Taihu and its relationship with algal bloom

以太湖2005-2007年的连续监测资料为基础,运用聚类分析和自相关分析方法,针对总无机磷、总无机氮、水温等环境理化因素与叶绿素a进行时空序列分析,初步归纳了当前太湖水质指标变化的空间特点、时间周期性及其与蓝藻水华暴发的关系.结果表明,太湖水质的空间分布大致分为三个入湖河口、四个湖湾、湖心区、西部湖区、东部湖区等十个区,其中入湖河口和北部湾区富营养化明显高于其他区,入湖河口的氮磷含量高于北部湾区,外源污染是造成水质恶化的根本原因.叶绿素a与总无机氮、铵态氮、水温呈显著相关关系,月平均指标显示水华暴发期集中在4-10月份,其中梅梁湾、贡湖和竺山湾为水华暴发的高发区,呈多峰形态.;Based on continuous monitoring data from 2005 to 2007 in Lake Taihu.spatisa and tempoml series wem analyzed using cluster analysis and self-correlation method for chlorophyll-a and total inorganic phosphorus, total inorganic nitrogen, water temperature and other physical and chemical faetom of the aquatic environment.The current spatial-temporal characteristics of water quality in Lake Taihu and their relationship with algal bloom are summarized.The results revealed that the spatial distribution of water quality roughly dividedintoten groups, includingthree estuaries, fourbays, center lake, westem area and eastern area. The dedree of eutrophication in estuaries and the northern bys was significantly higher than other area. while nitrogen and phosphorus in estuaries were higher than those in northern bays because of external 80urce pollution. A significant correlation between chlorophyll-a and total inorganic nitrogen, ammonia nitrogen, water temperature was noted. The monthly average chlorophyll-a displayed that algal bloom occurred from April to October and Meiliang Bay, Gonghu Bay。Zhushan Bay had high coincidence, showing multiple peaks.