沙漠水渠两侧不同坡向人工固沙区土壤水分空间变异特征  

Spatial Variations of Soil Water Contents in Artificial Sand-fixing Areas with Different Slope Directions around the Canal in Gurbantunggut Desert

作　　者：侯建秀 陶冶[2] 

机构地区：[1]新疆额尔齐斯河流域开发建设工程管理局,新疆乌鲁木齐830000 [2]中国科学院新疆生态与地理研究所干旱区生物地理与生物资源重点实验室,新疆乌鲁木齐830011

出　　处：《中国农村水利水电》2013年第2期12-16,20,共6页China Rural Water and Hydropower

基　　金：国家重点基础研究发展计划"973"项目(2009CB-825104)

摘　　要：在古尔班通古特沙漠中部引水渠两侧人工固沙区的阳坡和阴坡各选择一个样地(30m×30m),均匀划分为36个5m×5m的小样方,测定了各小样方中心10、30和50cm层的土壤体积含水量,采用半方差分析和克里格插值法对比研究了土壤含水量的空间变异特征。结果表明,2样地6层土壤含水量均呈正态或近似正态分布,均属中等变异(0.157～0.335)。无论阳坡或阴坡,下层土壤含水量均显著高于上层。除表层外,同一层次下阴坡的土壤含水量显著高于阳坡。半方差分析表明,6层土壤含水量空间变异最优模型均为指数模型;阳坡10cm层、阴坡10和30cm层的土壤含水量具有强烈的空间相关性,但变程较小(2.34～5.77m);余下3个变量具有中等空间相关性,变程较大(21.90～53.02m)。空间差值分析表明,阳坡3个土层的含水量均呈坡下低、坡上高的格局,阴坡50cm层也具有同样趋势;而阴坡10和30cm层含水量无明显规律,呈斑块状分布。阴坡较高的土壤含水量孕育了较丰富的草本植物,但草本植物的异质性分布可能也影响了阴坡浅层(10～30cm)土壤含水量的空间分布格局。Two sample plots （30 m× 30 m） are selected at shady and sunny slopes in artificial sand-fixing area beside the desert canal in central Gurbantunggut Desert, China. Each sample plot is divided into thirty-six 5 mN 5 m quadrats, and the soil volumetric water contents （SWC） at i0 cm, 30 cm and 50 cm layers in the center of each quadrat are measured by using a portable time domain reflec tometry （WET-2）. Then, the spatial variations of six soil water contents in two sample plots are analyzed by using semi-variance and Kriging interpolation methods. The results show that all SWCs at the six layers in two sample plots seem to be normal or approxi- mate normal distribution, and belong to moderate variation （coefficient of variance.. 0. 157±0. 335）. The SWC at lower layer is obvi- ously more than that at upper layer in each sample plot, and the SWC in shady plots is significantly higher than that in sunny plots at the same layer （except 10 cm layer）. The semi-variance analysis indicates that all SWCs at the six layers in two sample plots fit the exponential model. There is a strong spatial correlation between SWCs at 10 cm layer in sunny plots, and 10 cm and 30 cm layers in shady plots, but their lag distances （ranges） are relatively small （2.34-5.77 m） ; the rest of SWCs have moderate spatial correla- tion with larger ranges （21.90-53.02 m）. The Kriging interpolation shows that the three SWCs in sunny plots, as well as the SWC at 50 cm layers in shady plots, represent the pattern which the SWC is higher in the upper part of the sand dune and lower in the lower part; while the distributions of SWCs at 10 cm and 30 em layers in shady plots are irregular and blocky. Consequently, the higher SWC in shady slopes in artificial sand-fixing areas gestate the abundant herbs; however, the heterogeneous distribution of herbs also influence the distribution pattern of the shallow SWC （10-30 cm layer）.

关 键 词：人工固沙区 土壤含水量 空间变异 引水工程 环境保护 

分 类 号：TV91[水利工程—水利水电工程] X37[环境科学与工程—环境工程]