天津市重点河湖大型底栖生物多样性调查研究

Investigation of Macrobenthic Biodiversity in Key Rivers and Lakes in Tianjin

摘要: 为探究天津市重点河湖的大型底栖动物的群落结构特征，2021年对天津市8条国控入海河流及其主要支流、大运河在我市境内流经的北运河、南运河，以及主要水库及其汇入河流，共计24条河流、2个水库共计62个点位进行了野外调查，对底栖动物的种类组成、多样性以及群落结构进行分析。河流部分两期调查共采集到底栖动物17种，分属9目13科。其中节肢动物门3种，软体动物门13种，环节动物门1种；水库部分两期调查共采集到底栖动物44种，分属9目22科。其中节肢动物门30种，软体动物门12种，环节动物门2种。各水域底栖动物种类和数量存在差异，优势种不同，根据优势种分析显示，摇蚊是多个水系中的优势种。通过Shannon-Wiener多样性指数、Pielou均匀度指数和Margalef丰富度指数对底栖动物的平均密度和生物量进行了统计分析，结果显示两期数据对比三个生物多样性指数均普遍降低。选取底栖动物多样性综合指数作为评估指标，发现底栖动物多样性综合指数偏低，评价等级为较差级别以下。底栖动物作为重要的生态指标，其群落结构和多样性指数的变化可有效反映水环境质量。因此，应加强河湖底栖动物的监测工作，完善基于底栖动物的水质评价体系，以促进天津市河湖生态系统的良性循环。

Abstract: In order to investigate the community structure omacrobenthos in key rivers and lakes in Tianjin, field surveys were conducted in 2021 on eight state-controlled rivers entering the sea and their major tributaries, the North Canal and the South Canal through which the Grand Canal flows in the city, as well as the major reservoirs and their confluent rivers, a total of 24 rivers, two reservoirs and a total of 62 sites, to analyze the species composition, diversity, and community structure of benthic fauna. The species composition, diversity and community structure of benthos were analyzed. A total of 17 species of benthos were collected in the two phases of the river survey, belonging to 9 orders and 13 families. Among them, there are 3 species of Arthropoda, 13 species of Mollusca, and 1 species of Annelida; 44 species of benthos were collected in the two phases of the survey in the reservoir, which belong to 9 orders and 22 families. Among them, 30 species of Arthropoda, 12 species of Mollusca and 2 species of Annelida. There are differences in the species and number of benthos in each water body, and the dominant species are different. According to the dominant species analysis, the rocking mosquito is the dominant species in several water systems. The average density and biomass of benthos were statistically analyzed by Shannon-Wiener diversity index, Pielou evenness index and Margalef richness index, and the results showed that the biodiversity index was generally lower in the comparison of the two periods of data. The benthic diversity composite index was selected as the evaluation index, and it was found that the benthic diversity composite index was low and the evaluation grade was below the poor level. As an important ecological indicator, changes in the community structure and diversity index of benthos can effectively reflect the quality of water environment. Therefore, the monitoring of river and lake benthos should be strengthened and the benthos-based water quality evaluation system should be improved to promote the benign cycle of river and lake ecosystems in Tianjin.