陕北黄土区深剖面土壤水的多因子联合作用及主控因素  

Multi-factor Combined Action and Main Controlling Factors of Soil Water in Deep Loess Profiles in Northern Shaanxi

作　　者：张轩华 黄亚楠[1] 李志[1] ZHANG Xuanhua;HUANG Yanan;LI Zhi(College of Natural Resources and Environment,Northwest A&F University,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《水土保持研究》2023年第3期173-180,187,共9页Research of Soil and Water Conservation

基　　金：国家自然科学基金项目“黄土区潜水补给的方式、速率与控制因素”(42071043)。

摘　　要：[目的]探究黄土高原植被变化后深剖面土壤水与各环境因子的关系,并识别主要控制因素,对土壤水的综合调控具有重要意义。[方法]在陕北定边县采集农地、草地、沙柳和杨树>15 m深土壤样品,利用传统统计学和小波相干分析等方法解析多个因子对土壤水含量的联合作用及主导性。[结果]0-15 m,土壤水含量和储量的大小顺序为农地>草地≈沙柳>杨树,水分亏缺量为810,1 375,1 371,1 762 mm。基于小波相干分析的控制因子识别,发现土壤电导率是解释水分运移的单一主导因子,其与土壤水的正相干区域贯穿整个尺度。农地产生联合作用的双因子组合是电导率-砂粒,沙柳和杨树是磁化率-砂粒,主要增加了大尺度的相干区域。[结论]深层土壤水受土壤性质的影响更大,但植物的根系情况会严重扰动水分与土壤性质间的关系。[Objective]It is important to investigate the relationship between soil water and each environmental factor in the deep profile after vegetation change in the Loess Plateau and to identify the main controlling factors for the comprehensive regulation of soil water.[Methods]Soil samples were collected from farmland,grassland and the 15 m depth of the habitation of salix psammophila and Populus in Dingbian County,northern Shaanxi.The soil samples were analysed using traditional statistics and wavelet coherence analysis.[Results]The order of magnitude of soil water content and storage in 0—15 m was farmland>grassland≈salix psammophila>poplar,with water deficit of 810 mm,1375 mm,1371 mm and 1762 mm,respectively.Based on wavelet coherence analysis of control factors,soil electrical conductivity(EC)was found to be the single dominant factor explaining water transport,and the area of positive correlation between EC and soil water was found throughout the scales.The two-factor combinations that combined effect of farmland are EC and sand,and magnetic susceptibility and sand for the lands grown salix psammophila and poplar.The two-factor combinations enhanced the degree of coherence mainly at large scales.[Conclusion]Deep soil water is more influenced by soil properties,but plant root conditions can seriously perturb the relationship between water and soil properties.

关 键 词：土壤水分 植被变化 土壤因子 小波分析 

分 类 号：S152.75[农业科学—土壤学]