丰、枯水期里下河腹地典型水体浮游动物群落结构与水质评价

为了探究丰枯水期里下河腹地典型水体中浮游动物的群落结构特征,通过布设20个采样站点,于2014年丰水期(7月29日)和枯水期(12月24日)对里下河腹地典型水体进行了2次全面调查,并对水质状况进行了评价。结果表明,里下河腹地典型水体共鉴定出浮游动物21种(包括变种和变型),无节幼体1类;其中轮虫最多,共14种,占浮游动物总种数的66.6%;枝角类次之,共6种,占28.6%;桡足类最少,仅1种,占4.8%;各站点浮游动物种类组成和密度均以轮虫和枝角类为主,数量在5~15种,密度变化在9.8~102.2个/L。浮游动物相似性指数在0.18~0.55,平均为0.36,偏向于轻度相似,表明丰水期与枯水期的生境差异较大。优势种的优势度不高,在0.023~0.297;多样性指数在1.73~3.56,均匀度指数在0.67~0.95,表明丰、枯水期里下河腹地典型水体的浮游动物群落信息含量较大、群落结构处于较稳定状态。浮游动物多样性和水质监测结果均表明,枯水期水质优于丰水期,枯水期水质基本处于清洁状态,丰水期水质基本处于中度污染状态;污染源主要为面源污染,且串场河(6号)、新通扬运河(12号)、喜鹊湖(17号)、兴姜河(18号)受人类活动影响较大。

Zooplankton Community Structure and Water Quality Assessment in Typical Water Bodies of the Lixia River Basin in Dry and Wet Seasons

The zooplankton community structures of the typical water bodies in Lixia River hinterland in dry and rainy seasons of 2014 were researched. The results showed that 21 species of zooplankton and 1 class of nauplius have been founded in Lixia River hinterland. Among them, rotifer, 14 species, predominated in species, accounting for 66.6% of the total zooplankton species, cladoceran, 6 species, taken second place, accounting for 28.6% of the total zooplankton species. And the species number of copepoda was 1 species, accounting for 4.8% of the total zooplankton species. The species number and biomass of zooplankton in Lixia River hinterland ranged from 5 to 15 species and 9.8 to 102.2 ind/L respectively. Rotifer and cladoceran predominated both in species number and biomass. The analysis results of similarity showed that the similarity index ranged from 0.18 to 0.55, which meant the similarity indexes were low and the eco-environment differed significantly between dry season and rainy season. The analysis result of predominance index showed that the predominant indexes were not high, ranging from 0.023 to 0.297. The analysis results of diversity and uniformity showed that the diversity index and uniformity index ranged from 1.73 to 3.56 and 0.67 to 0.95, respectively, which meant that both diversity and uniformity of phytoplankton were good. So it could be concluded that the zooplankton community structures in Lixia River hinterland both in dry season and rainy season of 2014 were in a complex and integrate state. And zooplankton community structure in dry season was better than that in rainy season, according to the result of comparing the zooplankton community structure between dry season and rainy season.