岷江上游干旱河谷区林-农-草地土壤水分特征与数值模拟  

Moisture Characteristics and Numerical Simulation of Forest-farmland-grassland Soil in Arid Valley Region in the Upper Reaches of Min River

作　　者：唐香君 郭亚琳[1] 樊敏[1] 王青[1] 赵丽[1] Tang Xiangjun Guo Yalin Fan Min Wang Qing Zhao Li(School of Environment and Resource, Southwest University of Science and Technology, Mianyang Sichuan 621010)

机构地区：[1]西南科技大学环境与资源学院,四川绵阳621010

出　　处：《中国农学通报》2017年第7期128-133,共6页Chinese Agricultural Science Bulletin

基　　金：四川省科技厅科技支撑项目"地震灾区生态恢复与灾害防治关键技术研究"(2014SZ0058);四川省科技厅科技支撑项目资助"岷江上游山区农业生产区施肥对生态环境演变的响应特征"(15zx2104);四川省教育厅项目"岷江上游土壤环境质量对退耕还林驱动的林树下线下移的响应"(16ZB0139)

摘　　要：岷江上游干旱河谷土壤水分是农业生产和生态修复的关键因子。以干旱河谷典型区生态林、经果林、农地和荒草地4类土壤含水量为研究对象,通过对4类土壤含水量的变化分析和数值模拟,揭示土壤水分与土层深度的关系。结果表明:(1)土壤平均含水量依次为:农地(18.62%)>生态林(17.47%)>经果林(16.53%)>荒草地(11.25%);(2)从干旱河谷(1500 m)到天然林下线(2500 m)的山地垂直方向上,林地土壤含水量呈浅U型分布;海拔2100~2500 m土壤含水量均值为19.77%,海拔1900~2100 m为13.72%,海拔1500~1900 m为16.00%;(3)土壤水分随土层深度的增加而减少,生态林土壤水分垂直变化最为显著,农地土壤水分垂直变化则相对稳定;(4)土壤水分多水平贝叶斯模型能够较好地说明4种土地利用类型下土壤含水量的变化和剖面分布特征;(5)林地与荒草地土壤含水量差异表明,土壤平均含水量14%是界定林-草地的分界值。研究结果可为岷江上游干旱河谷生态修复提供数据支撑。Soil moisture in arid valley region in the upper reaches of Min River is the key factor of agricultural production and ecological restoration. Soil moisture of four typical land use types （ecological forest, economic fruit forest, cropland and wild grass ground） were investigated, the relationship between soil moisture and soil depth was analyzed through the mutation analysis and numerical modeling of soil moisture. The results showed that： （1） the average content of soil moisture was followed the order of cropland （18.62%） 〉 ecological forest （17.47%） 〉 economic fruit forest （16.53%） 〉 wild grass ground （11.25%）; （2） in vertical direction from the dry valley （1500 m） to timberline of the natural forest （2500 m）, soil moisture of forest land showed the distribution characteristics of shallow U shape; soil moisture average content was 19.77% at the altitudes of 2100-2500 m, 13.72% at 1900-2100 m and 16.00% at 1500-1900 m; （3） soil moisture decreased with the increases of soil depth, the vertical change of soil moisture in ecological forest was the most significant, while that of cropland was relatively stable： （4） the multilevel Bayesian model was good to illuminate the variation of soil moisture and profile distribution characteristics under this four land use types; （5） soil moisture in forest land and wild grass ground showed significant difference, the average soil moisture of 14% was the boundary value of forest land and wild grass ground. The research results could provide data supporting ecological restoration in the upper reaches of Min River.

关 键 词：土壤含水量 土地利用 多水平贝叶斯模型 岷江上游 

分 类 号：X321[环境科学与工程—环境工程]