林农复合系统灭螺机制及其持续灭螺

本文利用连续数年在试验基地观测和调查资料，结合五省其它试验点的研究结果，探讨了林农复合系统灭螺机制及其持续灭螺方法．结果显示，林农复合系统的小气候特征、土壤环境以及实施的耕翻间种措施等不利于系统内钉螺的孳生，使钉螺体内糖原含量明显减少，SDH、LDH活性下降，蛋白质总量和氨基酸含量降低，影响了钉螺的生存和繁殖．林农复合系统动态生长以及汛期外系统钉螺随水而来会影响灭螺．采用间伐、邻近草滩发展水产养殖以及在更大范围建立林农复合系统可以持续灭螺．

MECHANISM OF CONTROLLING ONCOMELANIA IN FOREST-AGROSYSTEM AND ITS PERSISTENT CONTROLLING

The impact of Forest-Agrosystem on the population of Oncomelania was investigated using multi-years experimental data.The reduction of the snail population was attributed to large variation of microclimatic and soil characteristics in the Forest-Agrosystem.Such microenvironmental variation significantly influenced the contents of glycogen and amino acid,and the activities of SDH and LDH in the snail,resulting in reduced growth and reproductivity of the snails.The effect of Forest-Agrosystem on the snail density may fluctuate during the dynamics of the system and the seasonal flooding.During which the snails can come from the neighhouring system,Thus,regular cutting to ensure intercropping and developing fish farming in the neighbouring grass land and establishing more Forest-Agrosystem in Low-middle reaches of Yangtse river may help control Oncomelania persistently.