入侵藁杆双脐螺迁移扩散机制研究

The Biomphalaria straminea，which as an important alien species, is one of the intermediate host of Schistosomiasis mansoni. Thus, it is of great importance to investigate the mechanism, and subsequently to find the effective way to control the spread of Schistosomiasis mansoni. But as a new emerging species, the current research on the mechanism of Biomphalaria straminea's migration and spread is still scarce. In this present study, we take the typical rivers in South China as the research area. A comprehensive method, including the field observation, flume experiment combined with physical and chemical analysis, is used to reveal the underlying mechanism. Firstly, the motion characteristics and dispersal form of the Biomphalaria straminea in water are studied by field investigation and flume experiments. Then, the ecological factors which influence the Biomphalaria straminea distribution and their quantitative relationship are discussed by in-situ observation and statistical analysis. Finally, a habitat suitability model for Biomphalaria straminea spread is developed to analyze the response of Biomphalaria straminea to the changing environmental condition. Based on these research, the mechanism of the Biomphalaria straminea migration and spread could be revealed. This research will help to to reveal the migration and spread law of Biomphalaria straminea’s distribution under different river habitat conditions, and guide the engineering practices for controlling spread of Biomphalaria straminea.

藁杆双脐螺是我国南方地区重要的入侵螺类，也是曼氏血吸虫的中间宿主之一。探明藁杆双脐螺的迁移扩散机理，是从源头上限制甚至阻断血吸虫病传播蔓延的有效手段。然而作为新型的入侵物种，其迁移扩散机制的研究还较为匮乏。本项目拟以华南地区的典型河道为研究区域，通过野外调查与观测、水槽试验和室内理化分析相结合的手段，揭示藁杆双脐螺在水体中的运动规律，弄清藁杆双脐螺随水流扩散的主要形式；分析研究藁杆双脐螺孳生分布的河道生境要素，明确藁杆双脐螺分布与生境要素间的定量关系；构建藁杆双脐螺分布的栖息地适合度模型，阐明生境要素变化下其迁移扩散的机制。项目开展有助于辨识藁杆双脐螺在不同河道栖息地条件下的迁移扩散规律，同时可为藁杆双脐螺的防控提供借鉴和依据。

藁杆双脐螺我国南方地区重要的入侵螺类，也是曼氏血吸虫的中间宿主之一。探明藁杆双脐螺的迁移扩散机理，是从源头上限制甚至阻断血吸虫病传播蔓延的有效手段。然而作为新型的入侵物种，其迁移扩散机制的研究还较为匮乏。本项目通过野外调查与观测，水槽试验和室内理化分析相结合的方法手段，研究了藁杆双脐螺在静水、动水条件下的沉降特性，分析在有无吸附力情况下藁杆双脐螺起动流速差异，建立了藁杆双脐螺静水沉降、动水沉降及起动流速公式；分析弄清了藁杆双脐螺随漂浮物扩散情况，明确了藁杆双脐螺在水体扩散的主要形式，揭示了藁杆双脐螺在水体中的运动规律。基于广义相加模型（GAM），筛选出影响藁杆双脐螺分布密度的主要生境要素,确定了藁杆双脐螺可能出现最大的分布密度的生境要素最适值，明确了藁杆双脐螺分布与生境要素间的定量关系。构建了藁杆双脐螺栖息地适宜度曲线，选择观澜河典型河段（桂花新村段），建立二维水力栖息地模型，模拟分析了不同流量下，该河段藁杆双脐螺栖息地适宜性变化，评价了不同时期流量变化对藁杆双脐螺栖息地的影响，项目研究可为藁杆双脐螺的防控提供借鉴和依据。