作　　者： ; ; ; ;

机构地区： 中国科学院亚热带农业生态研究所

出　　处： 《土壤学报》 2006年第4期554-562,共9页

摘　　要： 土壤水分空间变异性研究在喀斯特地区生态环境的恢复和重建过程中具有重要意义。通过网格（5m×5m）取样，用地统计学方法研究了喀斯特洼地典型区域（150m×50m）表层土壤水分（0～5cm和5～10cm）的空间变异特征。结果表明：土壤水分在采样区内呈比较简单的斑块状分布，相同性质斑块与土被连续分布区和石丛集中分布区范围相当；半变异函数在不同性质斑块内呈现出截然不同的变异特征，在整个采样区内表现出各向异性；旱季洼地表层土壤水分主要受石丛和地形两个不同尺度的环境因素影响；土壤水分具有一定的尺度效应，半变异函数的变程随着最小采样间隔增大而增大；当研究区域存在多重尺度的变异结构时，需要根据研究的目的和精度确定合理的采样尺度。 To quantify spatial variability of soil water is of important significance for ecological environment restoration in Karst regions. The geostatistics method is used to determine and quantify spatial variability of surface soil water （0 - 5 cm and 5 - 10 cm） for analysis of spatial patterns of soil water in a typical karst depression （ 150 m× 50 m） in Guzhou. Using the grid sampiing method （5 m ×5 m space）, 341 sampling points are fixed in total. Based on autocorrelation analysis, spatial correlation structure of these soil moisture patterns is calculated with the aid of the Moran＇s I index. Results indicate that the soil water contents in the two layers have a simple pattern of periodic variations, and patches with the same spatial autocorrelation character correspond to soil continuum and rock distribution in area. Sample variograms are found to have an anisotropy character in the whole research area. And in different patches, the semivariograms show different structure characters. The soil continuum patch has a low sill and a long.trudge, whereas the rock distributed patch has a high sill and a short range. Such soil water patterns can be explained by the effect of bare rock distribution and the topography of the research area. Based on the soil water content data, spatial scaling of soil moisture is further studied. The range of the soil water is increased with the sample spacing. This implies that when the spatial pattern is controlled by plural factors of different scales, sample spacing should be decided by the aim and precision of the research. The findings of this study may help improve the sampling design in the research on soil moisture in the Karst regions.

关 键 词： 喀斯特地区 峰丛洼地 土壤水分 旱季 空间变异性 地统计学

领　　域： [农业科学] [农业科学]