黄土区农草混合利用坡面土壤水分空间变异性  

Spatial Variability of Soil Water Content on a Cropland-grassland Mixed Slope Land in the Loess Plateau,China

作　　者：佘冬立[1,2] 邵明安[2] 俞双恩[1] 

机构地区：[1]河海大学南方地区高效灌排与农业水土环境教育部重点实验室,南京210098 [2]中国科学院教育部水土保持与生态环境研究中心黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100

出　　处：《农业机械学报》2010年第7期57-63,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金资助项目(90502006);黄土高原土壤侵蚀与旱地农业国家重点实验室基金资助项目(10501-250);河海大学自然科学基金资助项目(2009422411)

摘　　要：通过对黄土区农草混合利用坡面的土壤水分分析,研究土地利用结构对土壤水分空间变异特性的影响。结果表明,研究区坡面土壤水分呈中等变异,且农草混合利用结构明显增加了土壤水分的空间变异强度,坡面土壤水分具有明显空间结构性。干湿条件下坡面0~60 cm土层平均含水率的半方差最优理论模型分别为高斯模型和球状模型,且干旱条件较湿润条件下保持较高的基台值和变程,而块金值/基台值相对较低。Kriging插值结果显示坡面土壤水分呈现差异显著的斑块状分布格局,与坡面的混合土地利用结构一致。研究区浅层土壤水分空间变异及其分布格局主要受地形、降水和土地利用方式及其结构等因素的影响。The effects of land use structure on the spatial variation characteristics of soil water content were studied based on the survey of soil water condition on a cropland-grassland mixed slope land in the Loess Plateau.The results showed that the soil water content presented a moderate spatial variability on the slope scale.The cropland-grassland mixed land use structures significantly increased the spatial variability of soil water contents.The soil water content had obvious spatial structure.The Gaussian model and Spherical model were the best fitting descriptors for the mean soil water content of 0～60cm soil depth under arid and moist condition respectively.Compared to the moist condition,the mean soil water content had a higher sill and range,but a lower nugget-to-sill ratio under dry condition.The interpolation map by Kriging method showed that soil water content presented a significant different plaque distribution pattern,which was consistent with the mixed land use structure on the slope.The difference in the spatial variability and distribution pattern of soil water content（0～60cm） in the test area mainly were effected by topography,precipitation,land use and land use structure.

关 键 词：土壤水分 农草混合结构 空间变异性 

分 类 号：S152.7[农业科学—土壤学]