春秋两季鄱阳湖浮游植物物种多样性的比较研究

根据1999年6月和9月所采的样本,比较分析了中国鄱阳湖区春秋两季浮游植物的种类组成和物种多样性.该湖春、秋两季浮游藻类的物种数、数量及生物量依次为:68种和178种、1.76×107 cells/L和2.4×106 cells/L,21 mg/L和2.1 mg/L. 物种多样性分析结果显示,春、秋两季的物种多样性指数(H)值分别为0.7309～2.8098和0.3565～2.5913,群落均匀度指数(J)值分别为0.2941～0.9159和0.1351～0.8383,物种丰富度指数(R)值分别为0.3827～1.6382和0.5300～2.5605,生态优势度指数(C)值分别为0.2456～0.9091和0.3636～0.9587.结论是,秋季物种较春季丰富,数量和生物量则以春季为大,C平均值春季低于秋季,导致H、J平均值春季高于秋季.此次调查检出的种类中有18个属于有机污染指示藻类,且H平均值低于往年,提示鄱阳湖有向富营养化发展的趋势.

The Comparison of Species Diversity of Phytoplankton Between Spring and Autumn in Poyang Lake

The species diversity of phytoplankton in Poyang Lake was compared between spring and autumn through the samples collected in June and September 1999. A total of 68 and 178 species of phytoplankton were observed in June and September, respectively. The mean total cell numbers (MTCN) of phytoplankton in the whole lake were 1.76×107 cells/L and 2.4×106 cells/L, respectively, and the mean biomass (MB) were 21 mg/L and 2.1 mg/L. In June, diversity analysis showed that values of species diversity index (H) ranged from 0.730 9 to 2.809 8, evenness index (J) ranged from 0.294 1 to 0.915 9, species richness indexes (R) ranged from 0.382 7 to 1.638 2 and dominance indexes (C) ranged from 0.245 6 to 0.909 1. In September, H ranged from 0.356 5 to 2.591 3, J ranged from 0.135 1 to 0.838 3, R ranged from 0.530 0 to 2.560 5 and C ranged from 0.363 6 to 0.958 7. It can be concluded that the number of species in June was lower than that in September, while MTCN and MB were higher. The mean value of C in June was lower than that in September, which resulted in that H and J were higher. There were 18 common species belonging to those 80 species of the organic pollution-indicating algae. The H in 1999 was lower than those before. The study concluded that Poyang Lake was developing a trend of eutrophication.