摘要
土壤水分是黄土高原关键带水循环、地下水补给和植被恢复的关键因素。为揭示黄土高原关键带黄土整个剖面的土壤水分空间变化特征,通过土芯钻探的方式获取了黄土高原关键带5个典型样点(杨凌、长武、富县、安塞和神木)从地表到基岩的土壤水分样品,采用经典统计学和地统计学相结合的方法分析了剖面土壤水分的分布规律、变异特征及空间结构。结果表明:黄土高原关键带剖面土壤水分从南往北,土壤平均含水量由高变低;5个样点的土壤水分均为中等变异,随着深度由40 m增加到200 m,土壤水分变异性变弱,且样点之间的土壤含水量差异降低;地统计学分析表明样点的半方差函数能被理论模型较好地拟合(杨凌除外),指数模型能够描述大部分样点深剖面的空间变异结构。相关结果有助于了解黄土高原深层土壤水分状况及分布规律,对于黄土高原土壤水资源估算和区域植被恢复具有重要价值。
Soil water is central to our understanding of water cycle,groundwater recharge and vegetation restoration in the critical zone of the Loess Plateau. To ascertain the spatial variability of soil water for the entire profile in the critical zone of the Loess Plateau,we obtained soil samples from the top of soil profile to bedrock in five typical sites（ Yangling,Changwu,Fuxian,Ansai and Shenmu） based on soil core drilling and analyzed soil water vertical distribution,variation character and spatial structure in the entire soil profiles by classic statistics combining with geo-statistics. Results indicated that mean soil water content in the entire profile decreased at south-north direction in the critical zone of the Loess Plateau. Variabilities of soil water in the five sites all were moderate. Soil water variation in each site became weak gradually and difference in soil water content between the sites decreased as soil depth increased from 40 m to 200 m. Geo-statistics analysis demonstrated that semi-variogram of soil water content in the sites could be fitted well by theory model except Yangling site and exponential model could describe spatial variation structure in the most profiles. These results can benefit the understanding of soil water status and distribution regime in ultra-deep soil profile and are valuable for soil water resources estimation and vegetation restoration in the Loess Plateau.
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2017年第4期515-522,共8页
Advances in Water Science
基金
国家自然科学基金资助项目(41571130081
41371242)~~
关键词
土壤水分
空间变异
关键带
深剖面
黄土高原
soil water
spatial variability
critical zone
deep profile
Loess Plateau
