五趾跳鼠是内蒙古境内分布范围最广的鼠种之一。本文根据区内五趾跳鼠的形态差异，通过对其体长、耳长、尾长等5项外部性状特征及头骨14项特征的测量，运用SPSS11.0统计软件主成分分析和系统聚类分析，将所收集到的标本进行数值分类。结果表明，其前6个因子的累积方差贡献率已达到71.423%，通过分析各项测量指标在前6个因子上的因子负荷量最终确定了系统聚类所用的指标。根据聚类分析结果并结合各类群的分布特征将内蒙古地区的五趾跳鼠分为四大类，即应有四个亚种。

本文对内蒙古阿拉善地区不同生境中小型兽类群落的物种组成和多样性进行了初步研究。1998年8～9月和1999年8～9月，2002年10月，在8种不同生境类型中共布放54个样地，22606个有效铗日，捕获小型兽类标本866只，分属2 目6科，共20种。多样性分析结果表明：8种不同生境的小型兽类群落Shannon-Wiener多样性指数在1.186～1.589 之间；Pielou均匀性指数在0.6309～0.8618 之间；Simpson生态优势度指数在0.2349～0.4157之间；Margalef丰富度指数在0.9318～2.020之间。根据不同生境的小型兽类群落相似性指数聚类结果，可以将8种生境的小型兽类群落大致划分为4种类型：耐旱型（群落Ⅴ和群落Ⅶ）、干旱型（群落Ⅰ、Ⅱ、Ⅲ）、农林交错型（群落Ⅵ和群落Ⅷ）和森林型（群落Ⅳ）。生境条件的差异对小型兽类群落物种组成和多样性有一定的限制作用，而人为干扰有明显影响。

The rodents were investigated with trap-day method in Alashan Desert of Inner Mongolia from August to September 1998 and 1999. Sixty-five sites were selected according to conditions of vegetation, landform, topography and soil. The area of the site was 10 ha in which 400-500 traps were arranged. There were 1019 samples captured with 31 469 effective trap-days in all sites. The results showed that Meriones meridianus was a typical dominant species and Euchoreutes naso was one of representative rodents in Alashan Desert. The Alashan Desert was a new distribution region of Salpingotus crassicauda in China. Therefore, geographical distribution of the three rodents was analyzed with Map-info Professional 615 software of GIS (Geographical Information System). The results showed that the distribution maps of the three rodents, which were obtained on the basis of GIS, not only told the infor-mation of prophetical distribution of the three rodents in Alashan Desert, but also reported information of the rodents' distribution affected by habitat change, which can not be obtained by traditional site-distribution ways. This result can be used as scientific foundation for perfecting research design and monitoring harmful rodents in future.

根据库布其沙漠及其毗邻地区生境和鼠类分布的差异，应用系统聚类法，将该地区的鼠类划分为5个群落：（1）沙漠鼠类群落；（2）半荒漠区沙地鼠类群落；（3）荒漠鼠类群落；（4）荒漠化草原鼠类群落；（5）干草原鼠类群落。5个群落可聚为3个群落组。（1）沙地群落组；（2）半荒漠和荒漠群落组；（3）干草原群落组。同时对鼠类群落的多样性、均匀度等进行了初步分析。

1998年8～9月和1999年8～9月在内蒙古阿拉善地区对啮齿类进行了调查，捕到内蒙古兽类两个新记录种：间颅鼠兔(Ochotona cansus) 和肥尾心颅跳鼠(Salpingotus crassicauda)，经鉴定在国内属新的分布区。