普安县不同岩组类型对区域土壤侵蚀景观格局的影响

Effects of Different Petrofabric Types on Landscape Pattern of Regional Soil Erosion in Pu′an County

以普安县白云岩、石灰岩、砂页岩和玄武岩等不同岩组区域的土壤侵蚀景观作为研究对象,基于ArcGIS软件中Spatial Analysis拓展模块空间分析技术及景观生态学中的景观格局空间分析方法,从宏观空间尺度上研究了不同岩组类型对区域土壤侵蚀景观格局的影响。结果表明:普安县岩组分布特征是以白云岩为主,其次是石灰岩,砂页岩和玄武岩面积较少;石灰岩区总体侵蚀程度不高,但是局部侵蚀较为严重。普安县土壤侵蚀景观格局特征表现为:微度侵蚀是4种地层岩组土壤侵蚀景观的景观基质,微度侵蚀景观斑块在空间分布上集中连片、异质性低、均匀度指数高,极强度侵蚀与剧烈侵蚀最大面积比例与斑块面积都是最小,斑块在空间分布上距离都较远且及其破碎,连通性较低。普安县不同岩组土壤侵蚀景观格局存在差异,白云岩区景观最为破碎,具有较高的异质性;石灰岩区侵蚀斑块分布较为集中;玄武岩区具有最高的多样性,斑块间的信息交流最为频繁。

This study took the soil erosion landscapes of different petrofabric types in dolomite, limestone, sand shale, and basalt in Pu′an County as the research objects. Based on the module spatial analysis technology developed by spatial analysis in ArcGIS software and landscape pattern spatial analysis methods in landscape ecology, we examined the effects of different petrofabric types on the landscape pattern of regional soil erosion from the macroscopic spatial scale. The results show that: the distribution patterns of petrofabric in Pu′an County are dominated by dolomite, followed by limestone, and shale and basalt are less in area;the overall degree of erosion is not high in the limestone area, but the local erosion is more serious;the characteristics of landscape patterns of soil erosion in Pu′an County are as followings, slight erosion is a landscape matrix of soil erosion landscapes in four kinds of stratigraphic petrofabric, the patches of slight erosion landscape concentrate among the spatial distribution with low heterogeneity and high uniformity index, the maximum area percentages of extremely intensive erosion and intensive erosion, and patch area are the smallest, the patches are far apart and broken in space distribution, and the connectivity is low;the landscape patterns of soil erosion in different petrofabrics in Pu′an County are different, the landscape in the dolomite region is the most fragmented and has a high heterogeneity;the distribution of erosion patches in the limestone region is more concentrated;the basalt region has the highest diversity, and the exchange of information between the patches is most frequent.