潮白河中游河岸毛白杨水分来源分析  

Analysis on water sources of Populus tomentosa on middle reaches of Chaobai River bank

作　　者：韩通 张志强[1] HAN Tong;ZHANG Zhiqiang(Institute of Soil and Water Reservation,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学水土保持学院,北京100083

出　　处：《人民长江》2020年第6期79-88,共10页Yangtze River

基　　金：国家科技支撑计划项目“内蒙古及北京区域节水型城镇景观林培育与管理技术体系研究与示范”(2015BAD07B06-4)。

摘　　要：毛白杨(Populus tomentosa)是我国北方地区常见绿化树种,具有生长快、水分适应性强的特点,选择毛白杨营造河岸防护林可有效发挥防风固沙、保持水土、绿化美化和阻隔面源污染的重要作用。运用氢稳定同位素示踪的方法,选取潮白河中游河岸毛白杨作为研究对象,测定其茎杆水及其潜在水源(降雨、土壤水、地下水、河水)的氢稳定同位素比率δD,利用多元线性混合模型,计算了各水分来源的贡献率,结合降雨量、土壤含水量等环境因素分析了各水分来源贡献率变化情况,得出了潮白河中游河岸毛白杨的水分来源特点。分析结果表明:①距离河岸50 m及以远的潮白河中游河岸毛白杨对降雨、土壤水、地下水、河水均有利用,以利用土壤水为主,其他依次为降雨、地下水、河水。②降雨对毛白杨的贡献率随降雨量的增大而增加。③降雨量对毛白杨土壤水贡献率的影响表现为各层土壤水贡献率的层内变化和层间转换,随着降雨量增大,0~20 cm土壤水贡献率呈增大趋势、20~50 cm土壤水贡献率呈减少趋势,当降雨量大幅度增加,不同土层土壤水贡献率发生层间转换。④到河岸距离对毛白杨水分来源的影响主要表现为地下水、河水的贡献率及不同土层土壤水贡献率的整体结构,地下水、河水贡献率随到河岸距离的增大而降低。在距离河岸50 m处,毛白杨均衡利用各层土壤水;离河岸200 m处各土层土壤水对毛白杨的贡献率由浅到深递减;距离河岸400 m处,50~100 cm土壤水对毛白杨贡献率最高。Populus tomentosa is a common green tree species in northern China,which has the characteristics of fast growth and strong water adaptability.Riverside shelter forest formed by Populus tomentosa plays an important role in preventing wind and fixing sand,retaining soil and water,greening and beautifying,and blocking non-point source pollution.By using hydrogen stable isotope tracer method,this paper selected Populus tomentosa on the bank of middle reaches of the Chaobai River as the research object,and measured the hydrogen stable isotope ratio(δD)of its stem water and potential source water(rainfall,soil water,groundwater and river water).By using multivariate linear mixed model,the contribution rates of various water sources were calculated.Combining with environmental factors such as rainfall and soil water content,the variation of contribution rates of various water sources were analyzed.Then water source characteristics of Populus tomentosa were concluded.The results showed that:①The Populus tomentosa 50m from the riverbank and farther away used water from rainfall,soil water,groundwater and river,which use soil water as a main source and followed by rainfall,groundwater and river water.②The contribution of rainfall to Populus tomentosa increased with the increase of rainfall;③The influence of rainfall on the performance of the contribution rate of Populus tomentosa soil water lied in the change of soil water contribution rate within and between soil layers.With the increase of rainfall,0~20 cm shallow soil water contribution rate showed an increasing trend,and 20~50 cm soil water contribution showed a decreasing trend.When the rainfall increased sharply,soil water contribution rate change between different soil layers.④The influence of the distance from the river bank on the water source of Populus tomentosa was mainly manifested in the contribution rate of groundwater and river water and the overall structure of soil water contribution rate of different soil layers.The contribution rate of groundwa

关 键 词：毛白杨 水分来源 稳定同位素 多元线性混合模型 潮白河 

分 类 号：S157[农业科学—土壤学]