放逸短沟蜷断顶现象成因初探  

A Primary Study for Semisulcospira libertine’s Decollation

作　　者：唐骋[1] 朱家伟[1] 张甦洋[1] 李忠秋[1] 

机构地区：[1]南京大学生命科学学院,南京210093

出　　处：《四川动物》2012年第6期896-899,共4页Sichuan Journal of Zoology

基　　金：国家基础科学人才培养基金项目(J1103512)

摘　　要：在安徽省黟县洪星乡河流中的放逸短沟蜷断顶现象严重。本文对此断顶现象提出了河流流速和流段两个假说。通过比较在不同流速和流段的样方中取得之样本的螺体长和螺口宽的比值,证明放逸短沟蜷的断顶现象自上游至下游而愈发严重,而流速对其影响却很小。表明流段是影响放逸短沟蜷断顶的关键因素,而流速对于放逸短沟蜷断顶没有显著影响。A great number of Semisulcospira libertina are found decollated in the rivers of Hongxing town, Yixian county, Anhui province. To explain the phenomenon, two hypotheses on the flow rate and location are proposed respectively. By comparing the ratio of faucal width and body length of the samples from five quadrates according to the flow rate and loca- tion, it is proved that Semisulcospira libertina＇s decollation turns increasing severely from upstream to downstream while the .flow rate contributes little to it. The results showed that the location but not the flow rate influences Semisulcospira libertina＇s decollation mostly.

关 键 词：放逸短沟蜷 断顶 水流流速 流段 上下游 

分 类 号：Q958[生物学—动物学]