华北农牧交错带农田-草地界面土壤水分的空间特征  

Spatial pattern of soil moisture at the cropland-grassland boundary in agro-pastoral transitional zone of North China

作　　者：王红梅[1] 王堃[2] 米佳[2] 谢应忠[1] 

机构地区：[1]宁夏大学农学院草业科学研究所,银川750021 [2]中国农业大学动物科技学院草地研究所,北京100193

出　　处：《应用生态学报》2010年第3期604-612,共9页Chinese Journal of Applied Ecology

基　　金：国家重点基础研究发展规划项目(2007CB106800);国家科技支撑计划项目(2006BAD16B06);宁夏大学科学研究基金项目(ndzr09-36)资助

摘　　要：利用经典统计与地统计学方法,对华北农牧交错带农田-草地界面不同采样粒度(1m×1m、2m×2m)0～50cm土层土壤水分的空间异质性进行了分析.结果表明:研究区农田、草地、农田-草地界面土壤水分均属中等变异,草地土壤水分的变异系数较农田大;土壤水分的变异系数随土层深度的增加而逐渐增大,且1m×1m采样粒度下农田-草地界面土壤水分变异系数与土壤深度呈显著相关(P<0.05);1m×1m采样粒度下,农田-草地界面各土层土壤水分的空间异质性明显高于邻近的农田和草地,表现为中度到强度的空间自相关性,变程在7.65～30.99m,且具斑块分布格局;2m×2m采样粒度下,农田-草地界面各土层土壤水分的空间结构既有中到强度的空间自相关性,又有完全随机化的纯块金效应,变程在4.16～18.86m;在农田-草地边界存在土壤水分的界面效应.By the methods of classic statistics and geostatistics, this paper analyzed the spatial heterogeneity of soil moisture at 0-50 cm depth in different sampling grain sizes （1 m×1 m and 2 m×2 m） at the cropland-grassland boundary in agro-pastoral transitional zone of North China. In study area, the soil moisture at 0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm, and 40-50 cm depths of cropland, grassland, and cropland-grassland boundary presented moderate variance, and the coefficient of variation （CV） of grassland was higher than that of cropland. The CV increased with soil depth, and a significant linear regression relation（P〈0.05） was observed between them in sampling grain size 1 m×1 m. In sampling grain size 1 m×1 m, the spatial heterogeneity of soil moisture at different depths was obviously higher at cropland-grassland boundary than in cropland and grassland, which had a moderate to strong spatial dependency, and the range （A0） was 7.65-30.99 m; whereas in sampling grain size 2 m×2 m, the spatial distribution of soil moisture at cropland-grassland boundary had both the moderate to strong spatial dependency and the pure nugget effect, and the A0 was 4.16-18.86 m, suggesting that there existed ecological edge effect of soil moisture at cropland-grassland boundary.

关 键 词：农田-草地界面 土壤水分 空间异质性 界面效应 

分 类 号：S152.7[农业科学—土壤学]