Zhao Ya Nan, Zhou Yu Rong, Wang Hong Mei
School of Agriculture, Ningxia University, Yinchuan 750021, China.
Ministry of Education Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in Northwest China, Yinchuan 750021, China.
Ying Yong Sheng Tai Xue Bao. 2018 Nov;29(11):3577-3586. doi: 10.13287/j.1001-9332.201811.001.
Combined with geographic information system (GIS) data, the spatial heterogeneity of soil water in the 0-200 cm soil layer of the desert steppe with the introduction of the shrub Caragana korshinskii in eastern Ningxia was studied by classical statistical and geostatistical methods. It was found that the soil water content of each soil layer in the 0-200 cm profile was relatively low, ranging from 0.6% to 19.0% (averaged 4.4%). The coefficient of soil water content variation ranged from 49.5% to 86.3%, which indicated moderate spatial heterogeneity. The variation of soil water content at the 0-60 cm and 80-120 cm soil layers fitted the spherical model, while that at the 60-80 cm soil layer fitted the exponential model and that at the 120-200 cm soil layer fitted the Gaussian model. Soil water content at different soil layers showed different degrees of spatial autocorrelation. The nugget/sill [C/(C+C)] of soil water content in the 0-40, 60-80, and 120-200 cm soil layers ranged from 26.1% to 49.9%, with moderate spatial correlations. The nugget/sill of soil water content in the 40-60 cm, 80-100 cm, and 100-120 cm soil layers ranged from 15.5% to 22.1%, with strong spatial correlations. The scale of spatial heterogeneity in soil water content (A) varied among soil layers. The A was relatively large in the 0-20 and 20-40 cm soil layers (37.10-45.18 km) and small in the 40-200 cm soil layers (3.58-8.66 km). The results indicated that the introduction of C. korshinskii shrubs into desert grassland for vegetation recovery in recent decades have depleted soil water and accelerated the depletion of soil water in the deep layer (40-200 cm), leading to spatial heterogeneity and fragmentation of soil water (0-200 cm) with stronger effects at deep soil layer.
结合地理信息系统（GIS）数据，运用经典统计学和地统计学方法，对宁夏东部引入柠条锦鸡儿灌木的荒漠草原0 - 200 cm土层土壤水分的空间异质性进行了研究。结果表明，0 - 200 cm剖面各土层土壤含水量相对较低，范围为0.6%至19.0%（平均4.4%）。土壤含水量变异系数范围为49.5%至86.3%，表明存在中等程度的空间异质性。0 - 6 m和80 - 120 cm土层土壤含水量的变异符合球状模型，60 - 80 cm土层符合指数模型，120 - 200 cm土层符合高斯模型。不同土层土壤含水量表现出不同程度的空间自相关性。0 - 40、60 - 80和120 - 200 cm土层土壤含水量的块金值/基台值[C/(C + C)]范围为26.1%至49.9%，空间相关性中等。40 - 60、80 - 100和100 - 120 cm土层土壤含水量的块金值/基台值范围为15.5%至22.1%，空间相关性强。土壤含水量空间异质性尺度（A）在各土层间存在差异。0 - 20和20 - 40 cm土层的A相对较大（37.10 - 45.18 km），40 - 200 cm土层的A较小（3.58 - 8.66 km）。结果表明，近几十年来在荒漠草原引入柠条锦鸡儿灌木进行植被恢复，消耗了土壤水分，加速了深层（40 - 200 cm）土壤水分的消耗，导致0 - 200 cm土壤水分的空间异质性和碎片化，对深层土壤的影响更强。
