中点位移中性景观模型对不同主题景观的模拟分析

Simulation Analysis of Mid-point Displacement Neutral Landscape Model to Different Theme Landscape

在景观图幅大小、景观类型数和景观各类型所占比例等与4类真实景观相同的基础上,采用中点位移(mid-point displacement,MPD)中性景观模型,通过设置等间隔变化的空间自相关参数生成10个梯度的中性模拟景观,应用景观指数分析了模拟景观对不同主题真实景观的模拟情况。结果表明,MPD中性景观模型在斑块数、分维数、聚集度等指数方面能够很好地模拟4个主题的真实景观;而在边界密度、散布与并列等指数方面,对4个主题景观的模拟效果不佳。MPD中性景观模型只能在某些方面较好地模拟真实景观,并不能对真实景观进行全面模拟。虽然主题不同,但MPD中性景观模型并未有效区分模拟效果好坏,只是指数重合参数范围不同。在指数表现方面,本研究中某些结果与前人研究结果有偏差,说明不同中性景观在景观格局不同方面的表现存在差异,在模型选取时需慎重。

The mid- point displacement （MPD） neutral landscape model was tested against four real landscapes across a 10 -step gradient while constraining the same map size, the number of landscape types and the proportion of each landscape types. This paper analyzed whether there are differences in the simulation of different theme landscapes. Measurements of some mettles （TA, FRAC_ AM and AI） suggested that definite level of consistency between simulated landscape and real landscape did exist at class level. The ED and IJI didn＇ t show any agreement between simulated landscape and real landscape. MPD neutral landscape model can only simu- late the real landscape in certain aspects and the coincidence parameters of the artificial landscape were greater than those of the natu- ral landscape. In addition, some results were in discrepancy with previous research results according to metrics behavior. This indica- ted different neutral landscape models may perform different in some aspect and the selection of models needs to be cautious.