富营养化与玄武湖浮游动物群落的演变

1986年4月-1987年3月对玄武湖浮游动物群落进行的调查结果与1976年4月-1978年1月调查结果相比,表明原生动物每dm~3水年平均个体数后次是首次的3.25倍,而轮虫、枝角类、桡足类每dm~3水的年平均数前次与后次相比,则分别为4.03倍、3.56倍和2.11倍。在种类、生物量、优势种等方面,10年间亦有明显的变化.玄武湖富营养化在继续发展.目前已达超富营养化状态。

Eutrophication and the changes of zooplankton cammunity in Xuan Wu Lake

Quantitative and qualitative Zooplakton samples from April 1986 to March 1987 were monthly manipulated. The investigation results, including species composition, the changes of numbers, taxa and distribution and the variance of dominative species and the diversity indes of protozoa, were compared with those at same sites from April 1976 to January 1978. After a decennium "s interval, the protozoa species composition decreased, their densities elevated, the average protozoa abundance increased 3.25 time. However, the densities of rotifer, cladacera and copepoda decreased, densities were down to 4.03 times, 3.56 times and 2.11 times respectively. At these sites, the species composition and dominantive species were entielly changed. The biomass of zooplankton and the diversity index of protozoa also were changed. The results showed that eutrophication in Xuanwu Lake was in continuous development.