鄱阳湖克氏原螯虾的分布现状及其群体外部形态聚类分析

CURRENT DISTRIBUTION OF PROCAMBARUS CLARKII(CRUSTACEA,DECAPODA,CAMBARIDAE)IN POYANG LAKE AND THE PRELIMINARY MORPHOLOGICAL CLUSTER ANALYSIS OF DIFFERENT POPULATIONS

克氏原螯虾(Procambarus clarkii)作为外来入侵物种,对淡水水生生物的多样性已构成严重威胁为国内外学者所共识。有鉴于此,本项目通过对环鄱阳湖湖盆地域9县(市)计12个调查点进行样本采集,并对其多个形态学指标进行测量和数据聚类分析,以探讨克氏原螯虾在该地域的地理分布现状。研究结果表明,克氏原螯虾在鄱阳湖湖盆地域已占据一定的生态地位,并呈现全湖广泛分布及泛滥孳生趋势,已形成对其他水生生物多样性和生态系统稳定的潜在威胁;聚类分析结果显示,鄱阳湖克氏原螯虾群体外部形态上分为两个类群,即星子县、永修县、共青城市群体为一类,鄱阳县、新建县、余干县群体聚成一类,两类群似不存在地域上的交叉,但尚不能说明这两类群为完全不同的群体。同时,提出了防控克氏原螯虾的可行性建议。

Procambarus clarkii is native to southern USA and northern Mexico. As an exotic invasive species,it has been well known throughout domestic and overseas that P.clarkii has made a severe threat to natural biodiversity of common freshwater aquatic organisms. Alien invasive species have become a serious environmental issue throughout the world. Therefore, the research collected specimens from 12 localities out of 9 counties （cities） covered by basin of the Poyang Lake,afterwards we measured various morphological features and analyzed the data, then finally probed the current possible distributing status of P.clarkii.The preliminary survey indicated that P.clarkii had been dominant species around basin area in the Poyang Lake, moreover,it presented broadly vigorous growth over the whole lake and the situation was likely getting worse, which had produced potential negative effects on other aquatic species and the ecosystem; and the yield of indigenous Macrobrachium presented a reducing trend year by year. Results from morphological cluster analysis showed that P.clarkii from the Poyang Lake could be divided into two groups; the first group covered the area of Xingzi, Yongxiu, Gongqing counties and the second one prevailed in Poyang, Xinjian, Yugan counties etc. The survey indicated there was no any obvious cross distribution phenomena between these two groups, nevertheless, they were not two totally distinct groups yet based on current research result. Meanwhile, this study also proposed some feasible preventive suggestions on the invasive species,which should be considered for adjusting the on-going policy of lake- controlling and fish moratorium.The current period of time of fish moratorium （from April to June） also almost covers the peak season of P.clarkii growing, developing and breeding. There might be applying a specific fishing policy aiming at P. clarkii in the Poyang Lake which can only allow fisherman to catch P.clarkii freely for controlling its amounts and potential population booming, not for other aquatical species at the same period time during fish moratorium. Furthermore, we still need to do more biological fundamental research work of P. clarkii and some systematic research involving its biological invasion mechanism.