Abstract: Objective To investigate the syngenetic and synecological characteristics of Leptospira host animals in the farmlands along Huaihe River, China. Methods Trap-at-night method was used to capture small animals in the farmlands along Huaihe River. Simpson index, Shannon-Wiener index, Pielou index, and Levins index, the indices of community dominance, diversity, evenness, and niche breadth, were used for the analysis of syngenetic characteristics and niche characteristics of Leptospira host animals in the farmland ecosystem. Results Of the animals captured in the farmlands along Huaihe River, Apodemus agrarius accounted for 89.80%, Crocidura attenuata 6.51%, and Rattus norvegicus, Mus musculus, and Cricetulus triton together 3.69%. The density of host animals was the lowest (5.54%) in 2006 and the highest (13.75%) in 2010. The diversity index, evenness index, and dominance index of the host animals along Huaihe River were 0.4338, 0.2696, and 0.8111, respectively. The spatial niche breadth indices of Ap. agrarius and C. attenuata were 0.8030 and 0.9353, respectively, but the spatial niche breadth indices of R. norvegicus, M. musculus, and C. triton were 0.3912 to 0.4220. The temporal niche breadth indices were 0.9185 to 0.9979 for all host animals except C. triton (0). Conclusion There are 5 species of Leptospira host animals in the farmlands along Huaihe River, among which Ap. agrarius is the dominant species and C. attenuata is also common. The host animal density increased in general in 2005-2011, with the peak level in 2010. The host animals have low diversity and evenness and high dominant concentration. Ap. agrarius and C. attenuata have good adaptation to farmland ecosystem and good farmland resource utilization ability. The competition between the species of host animals is not prominent, which may lead to the population outbreak of Ap. agrarius, so the regions along Huaihe River are high-risk areas of leptospirosis.

Key words: Leptospirosis, Host animal, Community diversity

摘要： 目的 研究沿淮农田区钩端螺旋体(钩体)宿主动物发生特点和群落生态学特征。方法 以夹夜法在农田捕获小型兽类。采用Simpson指数为群落优势度指数, 以Shannon-Wiener指数为多样性指数, 以Pielou指数为均匀性指数, 以Levins指数为生态位宽度指数, 并通过以上指数来描述群落发生特点和生态位特征。 结果 沿淮农田区宿主动物群落中黑线姬鼠占89.80%, 灰麝鼩占6.51%, 褐家鼠、小家鼠和大仓鼠共占3.69%, 2006年宿主动物密度最低为5.54%, 2010年最高为13.75%;沿淮农田区宿主动物多样性指数为0.4338, 群落均匀性指数为0.2696, 优势度集中指数为0.8111;黑线姬鼠和灰麝鼩空间生态位宽度指数分别为0.8030和0.9353, 但褐家鼠、小家鼠和大仓鼠的空间生态位宽度指数很低在0.3912～0.4220之间, 时间生态位宽度指数除大仓鼠为0外, 各宿主动物在0.9185～0.9979。结论 沿淮农田区钩体宿主动物有5种, 其中黑线姬鼠为优势种, 灰麝鼩为常见种;2005-2011年宿主动物密度呈上升趋势, 并且在2010年达到高峰;农田区宿主动物多样性低, 群落均匀性也低, 优势度集中指数高, 其中黑线姬鼠和灰麝鼩对农田生态环境的适应性强, 对农田资源的利用能力也较强;群落内种间竞争不突出, 容易发生黑线姬鼠种群数量暴发, 故沿淮地区仍然是钩体病发生的高风险地区。

关键词: 钩端螺旋体病, 宿主动物, 群落多样性