Spatial and temporal variability of 0-to 5-m soil-water storage at the watershed scale
Spatial and temporal variability of 0-to 5-m soil-water storage at the watershed scale
复制标题
流域尺度0-5米土壤水储量时空变化
DOI：
10.1002/hyp.13172
复制
发表时间：
2018
影响因子：
3.2
通讯作者：
Liu Bingxia
中科院分区：
文献类型：
--
作者：
Fu Zihuan;Wang Yunqiang;An Zhisheng;Hu Wei;Mostofa Khan M G;Li Xuezhang;Liu Bingxia
降雨模式、土壤水分分布和植物生长之间的动态关系对于水资源有限生态系统中水土资源的可持续保护至关重要。由于缺乏深层土壤水数据，在流域尺度上深层土壤水含量的时空变化还没有得到充分的表征。在黄土高原老冶漫渠流域进行了19个采样点的深层土壤水储量（SWS）研究，采样深度为5 m（n= 73）。在0 ~ 1.5 m土层，土壤水稳度与降雨强度呈高度相关，随深度增加，相关性逐渐减弱，但在1.5-5.0 m土层，土壤水稳度的变化滞后于降雨对土壤水分的补充。地慢波的地质统计学参数也高度依赖于深度，平均地慢波在两个相邻层中呈现相似的空间结构。SWS的时间稳定性表示的平均相对差异，相对差异的标准差（SDRD），和平均绝对偏差误差（MABE）是显着较弱的浅层比在较深的层。在流域尺度上，土壤组分和有机碳含量控制着SWS的空间格局。确定了一个代表性位置（研究中心57），以估计流域1 - 5 m层的平均SWS。SDRD和MABE的半变异函数通过各向同性球形模型进行最佳拟合，其空间分布具有深度依赖性。SWS的时间稳定性和空间变异性随深度增加而增加。本研究对青藏高原深层SWS的估算和水土可持续管理具有一定的参考价值，对世界其他类似地区也具有一定的借鉴意义。
Dynamic relationships among rainfall patterns, soil water distribution, and plant growth are crucial for sustainable conservation of soil and water resources in water‐limited ecosystems. Spatial and temporal variation in deep soil water content at a watershed scale have not yet been characterized adequately due to the lack of deep soil water data. Deep soil–water storage (SWS) up to a depth of 5 m (n= 73) was measured at 19 sampling occasions at the LaoYeManQu watershed on the Chinese Loess Plateau (CLP). At a depth of 0–1.5 m, the annual mean SWS was highly correlated with rain intensity, and the correlation decreased with depth, but within the layers at 1.5–5.0 m, the changes in SWS indicated a lag between precipitation and the replenishment of soil water. Geostatistical parameters of SWS were also highly dependent on depth, and the mean SWS presented similar spatial structures in two adjacent layers. Temporal stability of SWS as indicated by mean relative difference, standard deviation of the relative difference (SDRD), and mean absolute bias error (MABE) was significantly weaker at the shallow than at deeper layers. Soil separates and organic carbon content controlled the spatial pattern of SWS at the watershed scale. One representative location (Site 57) was identified to estimate the mean SWS in the 1‐ to 5‐m layer of the watershed. Semivariograms of the SDRD and MABE were best fitted by an isotropic spherical model, and their spatial distributions were depth‐dependent. Both temporal stability and spatial variability of SWS increased over depth. This study is helpful for deep SWS estimation and sustainable management of soil and water on the CLP, and for other similar regions around the world.