广东省水库的蓝藻污染状况与水质评价

Pollution by Blue-green Algae (Cyanophyta) in Reservoirs of Guangdong Province and Water Quality Evaluation

摘要:

于2000年的丰水期和枯水期对广东省19个大中型水库的浮游植物状况进行了调查,并根据浮游植物群落结构、多样性指数、蓝藻污染状况和营养状态指数对水库的水质进行了分析。结果表明,大部分水库为蓝藻型水体,优势种类主要是能产生毒素的微囊藻类,而且蓝藻种类数和细胞密度与水库水质密切相关。蓝藻细胞密度和百分比分别为0.1×10⁴-6728.4×10⁴ cells L^-1和0.53%-99.2%。大部分水库受到了一定程度的污染,属于中营养型;东江流域的新丰江水库和白盘珠水库水质优良,为贫营养型;而位于经济较发达的沿海地区的鹤地水库、石岩水库和契爷石水库已受到严重污染。东江流域和北江流域水库水质普遍较好,而粤西沿海地区和珠江三角洲地区水库则污染较为严重。

Abstract:

A phytoplankton and water quality survey was conducted in flood and dry seasons in 2000 in 19 typical reservoirs in Guangdong Province, China, in order to evaluate the trophic state and blue-green algae (cyanophyty) pollution. Results showed that many reservoirs were polluted by blue-green algae, of which the potentially toxic Microcystis was the dominant species and often took up over 50% of the total phytoplankton cell concentration. Cell density and percentage proportion of blue-green algae were 0.1×10⁴-6728.4×10⁴ cells L^-1 and 0.53%-99.2%, respectively. Furthermore, species richness and density of blue-green algae were closely related to the water quality. Results based on phytoplankton community structure and trophic state index(TSI) revealed that the trophic level was lower in reservoirs located at upper reaches of rivers and mountainous districts than at lower reaches and coastal regions. Moreover, the water quality of reservoirs in Dongjiang and Beijiang drainage areas were better than those in other water areas especially the west coastal area and the delta area of the Pearl River. Most reservoirs have been polluted to some extent and belonged to mesotrophic state, two in Dongjiang drainage area are oligotrophic, while other three which located in highly economic developing coastal areas are heavily polluted and enriched.