密云水库的浮游植物群落结构与密度

STRUCTURE AND DENSITY OF THE PHYTOPLANKTON COMMUNITY OF MIYUN RESERVOIR

1998年的调查研究显示 ,密云水库库区水体的浮游植物群落为硅藻 (Bacillariophyta) -绿藻 (Chlorophyta)型 ,细胞密度为 35 8.76× 10 4· L- 1。湖泊的营养特征为浮游植物响应型。1988～ 1998年库区水体总氮增长 48.7% ,总磷增长 31.2 % ,浮游植物细胞密度增长 41.7% ,库区水体已为中营养 ,并出现了富营养型浮游植物指示种类 ,例如斜生栅藻 (Scenedesmus obliquus(Turp) .Kütz.) ,铜绿微囊藻 (Microcystis aeruginosa Kütz.) ,湖泊色球藻 (Chroococcus limneticus L emm.)。水体向富营养化发展趋势明显。应加强水环境保护 ,增加密云水库流域植被覆盖度 ,净化、涵养水源 ,以保证密云水库向北京市供水的质量和数量。

This 1998 research found that the structure of the Miyun reservoir phytoplankton community was of a diatom green algae type, and the cell density is 358.76×10 4·L -1 . The nutritive peculiarity belongs to responding type of phytoplankton. From 1988 to 1998, the total nitrogen of water body increased by 48.7% and total phosphorus of water body increased by 31.2%. Over this period the cell density of phytoplankton also increased by 41.7%. The water body of the lake has reached a medium level of nutrition and eutrophic phytoplankton, (e.g. Scenedesmus obliquus (Turp.) Kütz., Microcystis aeruginosa Kütz. and Chroococcus limneticus Lemm.) are now common in the lake. The water body, which supplys water for Beijing, is approaching a eutrophic condition. In order to maintain the water quality and production of Miyun reservoir, it is essential that the water environment of the valley is protected and the vegetation cover of the valley is increased.