摘要
本文根据1973—1975、1979—1982年在武汉东湖进行的调查资料,并与1962—1963年他人的研究结果对比,总结了20年来,在东湖2个采样站上轮虫的种类演替和数量的变动。轮虫的种类明显地减少。Ⅰ站由1962—1963年的68种至1982年减为44种;Ⅱ站由56种减为49种。由原来Ⅰ站种类多于Ⅱ站演变为Ⅱ站多于Ⅰ站。轮虫的数量急剧增加。Ⅰ站轮虫的年平均值由1962—1963年的687个/升至1982年上升为3,555个/升;Ⅱ站由332个/升上升为1,538个/升。轮虫总数的变动曲线呈夏季和秋季二个高峰,冬、春季轮虫的数量均很低。本文从生态学的角度,对轮虫种类演替及其数量的发展趋势进行了探讨。
Summarizing the data of rotifers obtained in 1973—1975 and 1979—1982, and comparing with the results of Wang et al. (1965), the authors analyse the species succession and the change in the abundance for the past two decades at two sampling stations, station ⅰ and station Ⅱ, which are representative of the bay region and the pelagic zone, respectively.
The number of species decreased markedly from 68 species in 1962—1963 to 44 species in 1982 for station ⅰ, and from 56 species to 49 species for station Ⅱ. Therefore, in the 1960s the species number at station ⅰ was larger than station Ⅱ, but now the situation has been reversed.
In general, the standing crop of rotifers at station ⅰ is far much greater than at station II thoughout the year. In the pattern of seasonal fluctuation of abundance, the maximum population in each year is usually recorded in summer and in autumn, while the minimum is found in winter and in spring.
From the angle of ecology, the authors discuss the species succession as well as the seasonal change in abundance of rotifers in Lake Donghu and probe into the trend of development of rotifers in the lake.
