文献类型：期刊文献

中文题名：三峡库区秭归段大气降水δD和δ^18O特征及水汽来源

英文题名：Characteristics ofδD andδ^18O in Precipitation and Water Vapor Sources in Zigui Section of the Three Gorges Reservoir

作者：王婷[1] 高德强[1] 徐庆[1] 靳翔[2] 张蓓蓓[1] 左海军[1]

第一作者：王婷

机构：[1]中国林业科学研究院森林生态环境与保护研究所,国家林业和草原局森林生态环境重点实验室,北京100091;[2]北京禹冰水利勘测规划设计有限公司,北京100161

年份：2020

卷号：33

期号：6

起止页码：88-95

中文期刊名：林业科学研究

外文期刊名：Forest Research

收录：CSTPCD;;Scopus;北大核心:【北大核心2017】；CSCD:【CSCD2019_2020】；

基金：国家重点研发计划子课题(2016YFD060020106);中国林业科学研究院中央级公益性科研院所基本科研业务费专项资金重点项目(CAFYBB2017ZB003);国家自然科学基金项目(31870716)。

语种：中文

中文关键词：大气降水;氢氧同位素;过量氘;水汽来源;三峡库区

外文关键词：meteoric water;hydrogen and oxygen stable isotopes;d-excess;water vapor resource;the Three Gorges Reservoir Area

分类号：P426.6

摘要：[目的]研究长江三峡库区秭归段大气降水δD和δ^18O特征及水汽来源,揭示该库区森林生态系统水循环过程对气候变化的响应机制。[方法]运用氢氧稳定同位素技术测定并分析三峡库区秭归段2016年9月至2019年8月共3个水文年大气降水氢氧稳定同位素组成,建立三峡库区秭归段大气降水δD-δ^18O关系式;在年尺度和季节尺度上分析影响大气降水氢氧同位素特征主要环境因子,并用HYSPLIT验证其水汽来源。[结果](1)三峡库区秭归段大气降水氢稳定同位素(δD)和氧稳定同位素(δ^18O)的关系式为:δD=8.52δ^18O+20.11(R^2=0.96,n=186,p<0.01);大气降水δD(δ^18O)季节性变化明显,干季降水δD(δ^18O)富集,湿季降水δD(δ^18O)贫化。(2)在年尺度上,降水δD(δ^18O)与降水量和温度均呈显著负相关关系;在季节尺度上,降水量是影响库区湿季降水δD(δ^18O)值变化的主要因素。(3)过量氘(d)值与HYSPLIT气团轨迹模型结果均表明,该库区秭归段湿季大气降水主要受东南季风和西南季风所携带海洋水汽的影响;干季大气降水气团主要来自于亚欧大陆内部及局地的水汽蒸发。[结论]三峡库区秭归段大气降水氢氧同位素组成季节性变化受局地环境因子(降水量、温度)和不同水汽来源共同影响。降水δD和δ^18O呈现“降水量效应”和“反温度效应”。湿季降水来自海洋气团,干季降水为局地水汽蒸发和大陆气团主导。
[Objective]To reveal the responsive mechanism of the hydrological cycling in forest ecosystems to climate change,it is necessary to examine the characteristics of hydrogen and oxygen stable isotopes(δD andδ^18O,respectively)in precipitation,as well as water vapor sources of precipitation in Zigui section of the Three Gorges Reservoir Area of China.[Method]Using a stable isotope technique,examined the composition of rainfallδD andδ^18O in Zigui section of the Three Gorges Reservoir Area in three hydrological years from September 2016 to August 2019,and established the local meteoric water line.Investigated the main environmental factors affecting the hydrogen and oxygen isotopic characteristics of atmospheric precipitation on annual and seasonal scales.Furthermore,traced the sources of atmospheric water in this area by calculating the D-excess(d)in the precipitation,and verified the results of the sources through the HYSPLIT.[Result]The relationship betweenδD andδ^18O in rainfall wasδD=8.52δ^18O+20.11(R^2=0.96,n=186,p<0.01).PrecipitationδD andδ^18O values had obvious seasonal changes,low in the wet season and high in the dry season.On the annual scale,the rainfallδD andδ^18O were significantly negatively associated with temperature and precipitation.On the seasonal scale,precipitation was the main factor affecting the variation ofδD andδ^18O values in the wet season.According to d-excess and the HYSPLIT model,the precipitation water vapor during the wet season was mainly influenced by the ocean moisture carried by the southeast and southwest monsoon.During the dry season,the atmospheric vapor mainly derived from the Eurasian Continent and local water evaporation.[Conclusion]The seasonal variation ofδD andδ^18O in precipitation is affected by local environmental factors(precipitation and temperature)and different sources of water vapor in the study area.On annual scale,there were“precipitation effect”and“anti-temperature effect”.The precipitation water vapor in the wet season was mainly influenced by the ocean moisture while that in the dry season derived from the continent and local water evaporation.