【摘要】 为进一步了解南水北调将钉螺移至北纬33°15′以北地区后,钉螺能否生存繁殖并形成新的有螺区,本文采用现场定量放养的方法,对钉螺在山东济宁、江苏徐州和镇江三地的生存繁殖作了纵向观察比较.结果,6、12、18和24个月后,济宁钉螺死亡率依次为35.33%、95.18%、100%和100%,徐州为16.23%、79.57%、86.24%和76.73%,对照点镇江为10.93%、32.38%、30.68%和31.58%;钉螺在济宁的产卵量15.9301只/雌螺,卵的孵化率32.50%,二者均为对照点的1/3,新孵出幼螺成活率为0;徐州上述三项指标均低于对照点(P<O.01).观察提示,如果南水北调将钉螺移至北方,由于受温度、土壤等因素影响,钉螺难以正常生存繁殖并形成新的有螺区.更多还原

【Abstract】 In order to understand the probability of survival and multilication of Oncomelania snails in northern area with construction of Project of South-To-Northern Water Transfer in China, the observations were made on the survival and multiplications of the snails in the different latitude regions. The results showed that death rates of snails in Jining (35°23’ north latitude) for 6,12,18 and 24 months were 35.33%,95.18%,100% and 100% respectively and the death rate of snail in Xuzhou (34°21’ north latitude) were 16. 23% ,79. 57% ,86. 24% and 76.73%,but in the control group, Zhengjiang (32°10’ north latitude) were 10.93%, 32.38%,30.68% and 31. 58%,and significantly lower than in Jining and Xuzhou. The Oncomelania snails in Jining and Xuzhou produced less number of eggs and the hatching rates were reduced. The survival rates of young snail were low else in Jining and Xuzhou更多还原