人为不同干扰方式下荒漠啮齿动物群落格局年间变动趋势

The annual fluctuating tendency and patterns of desert rodent communities under human disturbance

2002-2007年,在阿拉善荒漠区的典型地区,选择了4种不同干扰方式的样地,分别为开垦区、轮牧区、过牧区和禁牧区,研究啮齿动物群落的变动趋势,在每种干扰方式的地段设计了标志流放区,面积为0.95hm^2,采用标志重捕法,每月连捕4d,同时在4种不同干扰方式的地区选择了4条线路取样,每条线路面积约10km2,采用铗日法调查,分别在4、7、10月份取样。结果表明,6个年度中啮齿动物群落的格局在4种不同的干扰方式下表现出不同特征,组成群落鼠类数量和生物量相对比例的年度变化特征均表变现为过牧区较突出。过牧区群落生物量年度变化趋势与数量变化趋势同,群落生物量的年度变化主要是由数量变化来决定的。开垦区群落生物量的年度变化主要是由数量变化来决定的。轮牧区、禁牧区群落生物量年度变化均与数量变化趋势不一致,受不同种间个体生物量和种内个体生物量的差异影响较大。

The four kinds of sites under different kinds of human disturbed were selected and the fluctuating tendency of rodent communities was studied in the typical region of the Alashan Desert of Inner Mongolia from April 2002 to October 2002,from April 2003 to October 2003,and from April 2004 to October 2004,from April 2005 to October 2005,from April 2006 to October 2006,and from April 2007 to October 2007,i.e.a farmland area,a rotational-grazing area,a over-grazing area and a prohibited-grazing area.The four kinds of mark-recapture samples and of line samples were taken in different human disturbance areas.The area of the Mark-recapturing sample was 0.96 hm^2 and that of the line sample was 40 km2.The samples were collected every month in the Mark-recapturing sites for 4 consecutive days and in line sites in April,July,and October every year.The results showed that there were different types of rodent communities under different kinds of human disturbance in Alashan desert in six years.The features of annual component number changes and biomass changes of rodent communities were both prominent on the over-grazing area.The annual component number change of rodent communities were the same as the annual biomass change of rodent communities on the over-grazing area.At the same time,the biomass change of rodent communities were mainly decided by the component number change on the over-grazing area and the farmland area.The component changes of rodent communities were not consistent with annual changes of biomass on the rotational-grazing area and the prohibited-grazing area due to different species and different individuals of same species had a great effect on the biomass change of communities.