Study On River-lake Ecosystem Health Assessment Based On Benthic Animal Integrity Index

This research select six rivers in tongling city ecosystem,in November 2020 in the city of tongling city carried out the typical lakes along the Yangtze river water system of large benthic animal research,analyzes the lakes ecosystem in the benthic animal community structure and distribution characteristics of building large benthic animals having integrity index,and the ecological evaluation.It is of great significance to effectively solve the environmental and ecological protection and restoration problems of Tongling city and to support the environmental protection of the Yangtze River.A total of 73 species of benthos were identified,belonging to 3 phyla and 6classes.The main group of benthos was Arthropoda(42 species),accounting for57.53%.The number of species of annelida was the second(19),accounting for26.03%;Mollusca 12 species,accounting for 16.44%.The average biomass and density of benthic animals in the river and lake ecosystems in Tongling city were51.81g/m~2 and 126.15%ind/m~2.The distribution of benthic species in different rivers and lakes in Tongling city was baedang Lake > Chenyao Lake > Fengsha Lake >Huanghu River > Caizi Lake > Shunan River.During the survey period,the shannon Weiner index of the river and lake diversity index of Tongling city ranged from 0.25 to 2.23,the richness index from0.37 to 3.28,and the evenness index from 0.23 to 1.0.For shannon-Wiener diversity index,the average value of shannon-Wiener diversity index was fengsha Lake >Huanghu Lake > Baidang Lake > Chenyao Lake > Caizi Lake > Shunan River.The average variation of Margalef richness index was caizi Lake > Baidang Lake >Huanghu River > Fengsha Lake > Chenyao Lake > Shunan River.The mean value of Pielou evenness index is huanghu River > Chenyao Lake > Fengsha Lake > Baidang Lake > Caizi Lake > Shunan River.Based on the current situation of river and lake ecosystems in Tongling city,46 candidate parameters were selected to reflect the species richness,species diversity tolerance and feeding habits of benthic animals.Finally,the core index of the ecosystem biointegrity index in tongling city was established,which consisted of total number of taxa(M1),number of gastropod taxa(M7),Margalef abundance index(M26)and number of avulsion taxa(M37).Tongling city index of biological integrity of rivers and lakes ecosystem tallied with ratio method,it is concluded that tongling city rivers drainage 43 sampling points,9 of sampling point is "healthy" status,14 sample point is "sub-health state",five sampling points is "general" status,seven sampling point is "poor" state,eight sample point is "poor" state.The study on the river and lake ecosystem of the Tongling River is of great significance to the ecological protection and restoration of the rivers and lakes and the environmental protection of the Yangtze River.