为了讨论单一物种在异质性景观中的空间传播,将平均场近似模型和偶对近似模型的结果进行对比研究.本研究选择了有代表性的四邻域和八邻域时物种的传播情况,首先运用细胞自动机建立了理想模型,对偶对近似模型和平均场近似模型在全局密度和局域密度固定时随着出生率与死亡率比值变化的结果比较,以细胞自动机模型结果为依据,判断偶对近似与平均场近似哪个结果更加接近细胞自动机模型的结果.通过分析得到四邻域时在近似细胞自动机模型结果时偶对近似的结果优于平均场近似的结果,但是在八邻域时三个模型之间的差异性不再那么明显,偶对近似依然能够很好的预测细胞自动机模型的结果.
In order to discuss space spread of a single species in heterogeneous landscape, we compared the result of the mean-field approximation model and pair approximation model. This study discusses the spread of species in the four domains and eight domains.First,using Cellular Automata to establish an ideal model.When fixing the global density and local density to compare the mean-field approximation model and pair approximation model with the change of ratio of births and deaths.Based on the result of Cellular Automata to determine the mean-field approximation and pair approximation which is closer to the cellular automata model results.By analyzing the four domains,the results of pair approximation is more close the cellular automata than mean-field approximation,but the difference between three models is not so obvious in eight domain,pair approximation can still predict the results of cellular automata very well.