Abstract: The population dynamic changes of plateau zokor (Eospalax baileyi) is closely related to its reproductive performance that is influenced by the habitat condition. For clarifying the relationship between the reproductive performance of plateau zokor and its rangeland habitat condition, we selected two pastures with different zokor population densities to investigate the monthly changes of the botanical composition, total biomass, aboveground biomass, underground biomass, polysaccharide content of plant root, soil compaction, soil moisture as well as the zokor population density during the breeding season. Based on the Multi-way ANOVA and Independent sample T test analysis, the results showed that the may is breeding peak, the june is end of breeding. There was no significant difference in the reproductive performance between male zokors during the breeding seasons and female zokors during the breeding peak (P>0.05), there was significant difference in the reproductive performance in the end of breeding. The sex ratio of the zokor in the pasture with higher population density was greater than that in the pasture with lower population density during their reproduction peak. However, the sex ratio of the zokor in the pasture with lower population density was greater than that in the pasture with higher population density during the early and final breeding period. There was no significant difference in the botanical composition, total biomass, aboveground biomass, underground biomass between the two pastures with higher and lower zokor population density(P>0.05), however, the polysaccharide content of plant root had significant difference in the soil depth (0-30 cm) between the two pastures (P<0.05). There was no significant difference in the soil compaction except in the soil depth (0-20cm) between the two pastures with different zokor population densities (P>0.05), the soil moisture had significant difference in the soli depth from 0 to 30cm(P<0.05). The results indicated that the changes of the zokor reproductive performance was related to the polysaccharide content of plant root and soil moisture and unrelated to the botanical composition, total biomass, aboveground biomass, underground biomass, soil compaction and moisture.

Key words: Plateau zokor, Reproductive characteristics, Habitat condition, Pasture quality

摘要： 高原鼢鼠种群密度动态变化与其繁殖特性密切相关，而繁殖特性又与其栖息环境有关。为了解高原鼢鼠繁殖特性与其栖息草地质量的关系，本文在祁连山东段选择两个不同高原鼢鼠种群密度分布区，在其繁殖期调查各密度区雌雄个体不同月份的繁殖特性、草地生物量、植物组成、地下根系重量及根系可溶性糖含量、土壤紧实度和水分变化。通过多因素方差分析和独立样本T检验研究繁殖特性与草地质量的关系。结果显示：在高原鼢鼠繁殖期，5月为繁殖高峰期，6月进入繁殖末期；不同种群密度区之间个体繁殖强度无显著性差异（P>0.05）；雌性繁殖强度在繁殖高峰期无显著性差异（P>0.05），而繁殖末期存在显著差异（P<0.05）；高原鼢鼠性比在繁殖高峰期表现为低密度区大于高密度区，而在繁殖初期和繁殖末期为高密度区大于低密度区；两个种群密度区之间，草地植物组成、草地地上生物量、可利用草地生物量和地下生物量无显著性差异（P>0.05），而0-30 cm土层根系根可溶性糖含量存在显著性差异（P<0.05）；除高原鼢鼠采食深度（0-20 cm）外，不同密度区土壤紧实度无显著性差异（P>0.05），而0-30 cm土层土壤水分含量存在显著性差异（P<0.05）。结果表明在一定种群密度下，高原鼢鼠繁殖特性的变化与地下根可溶性糖含量和土壤水分有关，而繁殖特性与草地植物学组成、草地生物量无显著关系。

关键词: 高原鼢鼠, 繁殖特性, 种群密度, 草地质量