关键词: 啮齿动物, 密度, 达乌尔黄鼠, 相关分析, 多样性, 分段Logistic 模型

Abstract: According to the population of rodents inWuningbatu Sumu, Zhengxiangbai Qi, Inner Mongolia Autonomous Region during 1974～1993, the authors have found that there were 13 rodent species, with Citellus dauricus (67.85% ) as the dominant species and Allactaga sibirica (10.16% ) came second, the common species were Meriones unguiculatus, Microtus brandti and Ochotona daurica, and the other species were very few.The correlation between the number of individuals ( the sum of population densities of rodents in unit area) and density of C. dauricus was positive (P < 0.0001) , between A .sibirica and the number of individuals, and between A.sibirica and C. dauricus were negative, respectively (P < 0.001). The regression model was ( the number of individuals) = 1.065+ 0.916 (density of C. dauricus) + 0.310 (density of A . sibirica) (P < 0.0001). The diversity and evenness of rodents were influenced significantly by the density of C. dauricus. In another part, a Logistic piecewise model of the population growth N (t) = K/{1+ { [K- N (t₀) ] /N ( t₀) } exp {- [ r₀ ( t- t₀) + ( r₁- r₀) (t- t_c) H (tt_c)]}} was introduced, where N ( t) was a population density at time t, K was a carrying capacity, r₀ and r₁ were instantaneous rates of increase, t_c was a change point, H ( t- t_c) = 1,t≥t_c, and H ( t- t_c) = 0, otherwise. The parameters and the change point were determinted at the same time by the multivariate secant ( DUD, Doesn’t use derivatives) method of the nonlinear model. Finally, two simulation examples in the density of C.dauricus and the number of individuals were given respectively.

Key words: Rodent, Density, Citellus dauricus, Correlation analysis, diversity, Logistic piecewise model