三峡库区浮游生物群落DNA结构与水体理化因子的分析

DNA STRUCTURE ANALYSING OF PLANKTON COMMUNITY AND PHYSICO-CHMICAL FACTORS IN THE THREE-GORGES RESERVOIR REGION

本文对三峡水库大坝至香溪河段所设A、B、C、D、E、F和G等7个站点浮游生物群落DNA进行了RAPD分子生物学研究,并分析了其与水体理化因子的关系。各站点间RAPD研究表明:D和E首先聚到一组,然后与A聚到一起,最后与C聚成一大类;B和F聚成一大类;站点G独自归于一类。而理化因子聚类结果显示:B首先与C聚为一小类,再与D聚到一起,然后与G、F聚成的小类聚为一类,而E与A分别单独归为一类。比较发现,RAPD聚类结果中相距较近的站点在理化因子聚类中显示为相距较远的站点(如站点A、C、D、E之间),而在RAPD聚类中相距较远的站点在理化因子聚类中显示为相距较近的站点(如站点B、F分别与G之间)。这可能因为它们之间存在负相关性,也可能部分因为试验条件本身所造成的误差。本实验为确定浮游生物DNA指纹结构与理化因子的关系提供了新的信息,进而为建立一种新的水质评价体系积累了理化因子的一些背景资料。

Along with the development and progress of society economy, dams have been playing increasing important roles, and so does the Three-Gorges Dam. Inevitably,hydrobios, hydrochemistry and other key physico-chemical factors of water body were altered. In order to evaluate these changes,many pursuers study water quality through bio-detectors and physico-chemical factors. But both of the two methods failed to compare from different studies since different bio-detector and physico-chemical factors were adopted. In this paper,the author tries to probe into a new way through discussing the relationship between DNA structure of plankton community and physico-chemical factors in the Three-Gorges Reservoir region （TGRR）. Random amplified polymorphic DNA （RAPD） was used to analyze DNA structure of plankton community, and got the result that 7 locations clustered into 3 groups. Station D and E clustered together at first, then A and C joined in this group; B and F was as another group,and G was different from all the others. While the physico-chemical factors clustering showed that station B and C clustered as a group at first,then adding D into this group; G and F clustered into another group; A and E was other two separated groups. After comparing, some stations such as A,C, D and E clustered close in RAPD while were away fram each other in physico-chemical factors. On the other hand,B-G and F-G clusteried apart from each other while reversed in physicochemical factors analysis. All the results indicated two possibilities： One was that DNA structure of plankton community under RAPD analysis and physico-chemical factors analysis of water body in the TRGG correlate negatively ; the other was because of the instantaneous samples, some natural and artificial factors, such as water flow, weather, man-made operations and so on, might affect the experiment results to some extent. Accordingly, new information about physico-chernical factors has been obtained,which is beneficial to affirm relationship of DNA structure of plankton community and physico-chemical factors. Further more,it is better for establishing a new assessment system of water quality.