桥山林区不同林分和坡位土壤水分对典型降雨的响应  

Response of Soil Moisture to Typical Rainfall at Different Stands and Slope Sites in Qiaoshan Forest Region

作　　者：郭义选 李婧[1] 徐国策[1] 张译心 陈曦[1] 谷丰佑 王斌[1] GUO Yixuan;LI Jing;XU Guoce;ZHANG Yixin;CHEN Xi;GU Fengyou;WANG Bin(State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China,Xi′an University of Technology,Xi′an 710048,China)

机构地区：[1]西安理工大学省部共建西北旱区生态水利国家重点实验室,西安710048

出　　处：《水土保持学报》2025年第1期84-93,101,共11页Journal of Soil and Water Conservation

基　　金：国家自然科学基金项目(42277191);陕西省教育厅重点科学研究计划项目(23JY057)。

摘　　要：[目的]降雨是土壤水分补给的主要来源,直接影响着土壤水分的分布特征,进而影响植被的生长状况,为探明桥山林区不同林分和坡位土壤水分对典型降雨的响应规律。[方法]以黄土高原南部桥山林区为研究对象,通过对典型林分(阔叶纯林和针阔混交林)不同土层深度土壤水分和降雨的监测,探究不同植被覆盖和坡位条件下的各层土壤水分体积分数对典型降雨的响应特征。[结果]1)研究期,降雨量主要集中在8月、9月、10月,其中9月的降雨量最大为251.7 mm。各样点同一土层的土壤水分体积分数季节性差异显著(p≤0.05),不同土层的平均土壤水分体积分数均在夏季最低。2)中雨事件仅浅层土壤水分体积分数对降雨发生响应,针阔混交林土壤水对降雨的响应强度>阔叶纯林。3)大雨事件土壤水对降雨的响应为针阔混交林大于阔叶纯林,不同坡位的响应关系为浅层坡下>坡中>坡上,深层坡上>坡中>坡下。4)暴雨事件土壤水对降雨的响应为阔叶纯林大于针阔混交林,不同坡位的响应关系为浅层坡下>坡中>坡上,深层坡上>坡中>坡下。5)在3场降雨中针阔混交林的补给量分别为纯阔叶林的1.55、1.65、1.00倍。[结论]探究桥山林区土壤水分对降雨的响应和浅层土壤水运动的过程,对桥山林区坡面降雨资源的优化配置和森林生态系统可持续恢复具有重要意义。[Objective]Rainfall is the main source of soil water supply,which directly affects the distribution characteristics of soil water,and then affects the growth of vegetation,to explore the response of soil moisture to typical rainfall at different stands and slope sites in Qiaoshan forest region.[Methods]The Qiaoshan forest area on the southern Loess Plateau was taken as the research object.Through monitoring the rainfall and soil moisture at different depths of typical stands(broad-leaved pure forest and mixed forest),the response characteristics of soil moisture at different layers to rainfall patterns under different vegetation cover and slope location conditions were explored.[Results]1)Rainfall during the study period was mainly concentrated in August,September and October,with the highest rainfall being 251.7 mm in September.The seasonal differences in soil moisture in the same soil layer at different points were significant(p≤0.05),and the average soil moisture in all soil layers was the lowest in summer.2)During moderate rainfall events,only shallow soil moisture content responded to rainfall,and the response intensity of soil moisture content to rainfall in mixed forest was greater than that in broad-leaved pure forest.3)In the event of heavy rain,the response of soil moisture to rainfall was greater in the mixed forest than in the pure broad-leaved forest,and the response relationship was as follows:lower slope>middle slope>upper slope for the shallow layer,and upper slope>middle slope>lower slope for the deep layer.4)In the event of heavy rainfall,the response of soil moisture to rainfall was greater in broad-leaved pure forest than in mixed broad-leaved forest,and the response relationship was as follows:lower slope>middle slope>upper slope for the shallow layer,and upper slope>middle slope>lower slope in the deep layer.5)In the three rainfall events,the supplement amount of the mixed forest was 1.55,1.65 and 1.00 times that of the pure broad-leaved forest,respectively.[Conclusion]It is of great signi

关 键 词：土壤水分 降雨响应 桥山林区 林分类型 

分 类 号：S152.7[农业科学—土壤学]