摘要:
Objective To investigate the relationship between fleas density of Spermophilus alaschanicue and host density as well as meteorological factors.Methods The densities of fleas of Spermophilus alaschanicue and meteorological temperature,precipitation,relative humidity data in the same period from 1977 to 2014 in plague natural foci of Spermophilus alaschanicue of Gansu Province were collected.In order to further establish the multiple linear regression and the stepwise regression analysis model,SAS 9.3 software was used to explore the linear correlation analysis between fleas index number,density of Spermophilus alaschanicue and meteorological factors.Results The average body flea index positively correlated with the density of Spermophilus alaschanicue (r =0.34,P < 0.05),in addition,hole fleas index was in negative correlation with the average temperature of the current and preceding first,second and third years (r =-0.44,-0.39,-0.45,-0.54,P < 0.01).However,hole fleas index positively correlated with the average rainfall of preceding first year (r =0.38,P < 0.05).More specifically,the monthly body flea index was negatively correlated with the average rainfall and the average temperature of current,preceding first,second,and third months,and the average relative humidity of current month (r =-0.23,-0.34,-0.43,-0.29,-0.25,-0.33,-0.36,-0.38,-0.26,P < 0.01).After multiple linear regression analysis,the following equations were obtained:body fleas index =3.983 1 + 0.695 1 × Sperrnophilus density-0.004 9 × average annual rainfall;hole fleas index =10.780 4 + 0.009 1 × average annual rainfall-0.216 2 × annual average relative humidity.Conclusions The relationship between fleas density of Spermophilus alaschanicue and the environment is complex,they have mutual connection as well as mutual restriction.Except Spermophilus density affects the number of fleas,the two most important meteorological factors which affect the flea body index are temperature and rainfall.In addition,the relationship between meteorological factors and flea body index shows somewhat lagging behind for two to three months.%目的 探讨阿拉善黄鼠寄生蚤数量与宿主数量和气象因素的关系.方法 收集1977-2014年甘肃省黄鼠疫源地内蚤数量数据和同期温度、降雨量、相对湿度等气象资料.采用SAS 9.3软件进行蚤指数与宿主数量和气象因素的相关分析,进一步建立蚤指数与黄鼠密度和气象因素多元线性回归模型和逐步回归模型.结果 黄鼠年体蚤指数与黄鼠密度呈正相关(r=0.34,P<0.05);年洞干蚤指数与当年及领先1(相对于当年作为参照的前1个年份)、2、3年平均温度呈负相关(r=-0.44、-0.39、-0.45、-0.54,P均<0.01),与领先1年平均降雨量呈正相关(r=0.38,P<0.05).月体蚤指数与当月及领先1、2、3月平均降雨量、平均温度,以及当月平均相对湿度均呈负相关(r=-0.23、-0.34、-0.43、-0.29、-0.25、-0.33、-0.36、-0.38、-0.26,P均< 0.01).经多元线性回归分析,体蚤指数=3.983 1+0.695 1×黄鼠密度-0.004 9×年均降雨量,洞干蚤指数=10.780 4+0.009 1×年均降雨量-0.216 2×年均相对湿度.结论 蚤类和宿主动物及环境间既相互联系又相互制约,除黄鼠密度影响蚤数量变动外,影响体蚤指数最大的两个气象因素是气温和降雨量,且影响存在2~3个月滞后效应.