基于马尔科夫模型土壤侵蚀动态变化研究——以西安都市圈为例

Dynamic Changes of Soil Erosion Based on Markov Model——A Case Study of the Xi'an Metropolitan

以西安都市圈为研究区域,采用遥感影像、DEM和经济社会统计数据等基础数据,通过RS和GIS技术,结合通用水土流失方程(RUSLE),对2000年、2005年和2010年西安都市圈土壤侵蚀动态变化情况做定量估算分析。在定量计算的基础上,应用马尔科夫模型预测2015年、2020年、2025年的土壤侵蚀演变情况。结果表明:(1)2000—2010年,从时间特征上来看,西安都市圈土壤侵蚀呈减小趋势;从空间特征来看,北部和南部区域土壤侵蚀比较严重,中心区域相对较轻。(2)2000—2010年,各类土壤侵蚀类型面积主要趋于由较高转向较低等级侵蚀类型,说明西安都市圈土壤侵蚀强度呈减小趋势。(3)从预测结果可以看出,2015—2025年,微度侵蚀面积在逐年增加,轻度及以上类型的面积逐年减少,整体呈良性发展趋势。

We took Xi′an metropolitan as the study area.Based on DEM data,remote sensing data and the economic and social statistics data,using RS and GIS technology,combining with the universal soil loss equation（RUSLE）,we analyzed the dynamic change of soil erosion in Xi′an metropolitan in 2000,2005and2010.On the basis of the quantitative calculation and application of Markov models,the dynamic changes of soil erosion areas of Xi′an metropolitan in 2015,2020,2025 were predicted.The results showed that：（1）from 2000 to 2010,on the view of time features,soil erosion presented the decreasing tendency in Xi′an metropolitan;on the view of spatial characteristics,soil erosion was more serious in north and south region,and was relatively light in central region;（2）from 2000 to 2010,various types of soil erosion areas shifted from higher to lower level erosion types,specification of Xi′an City circle of soil erosion intensity showed the trend of decrease indicating that soil erosion intensity presented the decreasing tendency in Xi′an metropolitan;（3）predicted value results show that,the tiny degree of soil erosion area will increase year by year,light and above the light degree soil erosion areas will reduce year by year from 2015 to 2025,the overall trend will tend to a status of benign development.