沙坡头人工固沙植被土壤水分空间异质性  

Spatial heterogeneity of soil moisture in Shapotou sand-fixing artificial vegetation area

作　　者：马风云[1] 李新荣[2] 张景光[2] 李爱霞[2] 

机构地区：[1]山东农业大学林学院,泰安271018 [2]中国科学院寒区旱区环境与工程研究所沙坡头沙漠试验研究站,兰州730000

出　　处：《应用生态学报》2006年第5期789-795,共7页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(40401004);国家重点基础研究发展规划资助项目(G2000048704)

摘　　要：利用传统统计学和地统计学相结合的方法对沙坡头人工固沙植被区0～200cm之间的各层土壤水分的空间变异性进行研究．结果表明，1）土壤水分相对变异较大的层是在160～180cm层和180～200cm层，变异系数分别为0．72和0．73．表层0～5cm层的相对变异也较大，变异系数为0．66．2）半方差函数分析结果表明，各层土壤水分均具有明显的空间变异性，各层土壤水分自相关部分的空间异质性占总空间异质性的程度很高，所占比例在87．7％～99．9％范围内．各层土壤水分的有效变程大小有较大差异，最小值出现在60～80cm层（7．04m），最大值出现在20～40cm层（19．71m），土壤水分有效变程从表层到深层没有明显的变化规律；3）土壤水分插值图反映出0～140cm之间相邻各层土壤水分变化较大，140～200cm各层土壤水分变化较小；4）土壤水分在0°、45°、90°、135°四个方向的半方差函数基本上是一条直线，表明在这四个方向上半方差和距离的相关性较低，土壤水分变化是独立、随机的，是同质性的．To explore the characteristics of soil moisture heterogeneity in sand-fixing artificial vegetation area is of significance in vegetation recovery and environment control in arid regions. With the methods of traditional statistics and geo-statistics, this paper studied the heterogeneity of soil moisture in the layers from 0 to 200 em in depth in Shapotou sand-fixing vegetation area. The results showed that the variation of soil moisture in layers of 160～180 and 180～200 cm was relatively larger, with the variation coefficient being 0.72 and 0.73, respectively, and the next was in top layer （0～5 cm）, with a variation coefficient of 0.66. Semi-variance analysis showed that the autocorrelation of soil moisture spatial heterogeneity in total spatial heterogeneity was high, ranging from 87.7% to 99.9%. The scale of spatial heterogeneity in different soil layers was different, with the minimum in 60～80 cm layer and the maximum in 20～40 cm layer, but no regular changes being observed from surface to deep layers. The colorful contour maps of Kriging interpolation indicated that the variation of soil moisture was larger in 0～140 cm layer than in 140～200 cm layer. The correlation between semi-variance and distance in four directions of 0°, 45°, 90° and 135° was weak, suggesting that the variation of soil moisture was independent, random, and homogeneous.

关 键 词：固沙植被 土壤水分 变异函数 空间异质性 

分 类 号：S152.7[农业科学—土壤学]