藻类聚集对太湖水环境的影响研究

Study on the Effect of Algal Accumulation on the Water Environment of Taihu Lake

为探究藻类聚集对湖泊水环境的影响,本研究选取太湖藻类聚集区(竺山湾符渎港近岸带)和开阔水域作为研究区域,从2020年6月-2021年5月定期对研究区域水环境开展调查研究,分析了水体溶解氧(DO)、pH、氧化还原电位(ORP)、总有机碳(TOC)、总氮(TN)和总磷(TP)等指标变化趋势。结果表明:藻类聚集区上覆水的叶绿素a含量高于开阔水域,大量的藻类聚集衰亡降低了上覆水DO浓度,使水体DO浓度降低至接近0 mg·L^(-1),形成缺氧的环境;藻类聚集区上覆水的TOC、TN、TP的浓度大幅上升,最高分别达到112.53,8.82和1.30 mg·L^(-1)。湖泊藻类聚集导致了湖泊水环境质量的下降,加剧了水体富营养化,因此对湖泊藻类聚集区通过定期打捞减少藻类堆积厚度,可以有效减少藻源性营养盐的输入,减缓水体富营养化进程。

In order to explore the impact of algae aggregation on the water environment of the lake,this study selected the algae aggregation area of Taihu Lake(the nearshore zone of Fudu Port in Zhushan Bay)and open water as the study area.From June 2020 to May 2021,the water environment in the study area were investigated regularly.The variation trend of dissolved oxygen(DO),pH,REDOX potential(ORP),total organic carbon(TOC),total nitrogen(TN),total phosphorus(TP)and other indexes were analyzed.The results showed that the content of chlorophyll a in the overlying water was higher than that in the open water.A large number of algae aggregation and decay reduced the DO concentration of overlying water,reduced the DO concentration of water body to nearly 0 mg·L^(-1) ,and formed an anoxic environment.The concentrations of TOC,TN and TP in the overlying water increased significantly,reaching 112.53,8.82 and 1.30 mg·L^(-1) respectively.The algae aggregation in lakes leads to the decline of water environment quality and intensifies the eutrophication of water body.Therefore,the algal aggregation area in the lake can be regularly salvaged to reduce the thickness of algal accumulation,which can effectively reduce the input of algal derived nutrients and slow down the eutrophication process of water body.