摘要
河水氢氧稳定同位素特征是研究水体转化和示踪水循环过程的重要内容.为研究河水氢氧稳定同位素特征,揭示河水补给来源,于2017年4—8月对亚热带农业小流域脱甲河4级河段(S_1、S_2、S_3和S_4)水体氢(D)、氧(^(18)O)稳定同位素进行了监测,分析其时空动态特征和过量氘(d-excess)的变化规律,并探讨了它们与降水、高程和水质等影响因子的相关关系.结果表明:δD、δ^(18)O和d-excess的变化范围分别在-43.17‰^-26.43‰(-35.50‰±5.44‰)、-7.94‰^-5.70‰(-6.86‰±0.74‰)和16.77‰~23.49‰(19.39‰±1.95‰).受季风环流的影响,δD和δ^(18)O具有明显的季节变化特征,即春季(δD和δ^(18)O为-29.88‰±3.31‰和-6.18‰±0.57‰)>夏季(δD和δ^(18)O为-39.25‰±2.65‰和-7.32‰±0.42‰);空间上,δD和δ^(18)O表现出明显的沿程变化,随着采样点的位置到河流源头的距离波动增加,δD为S_1<S_4<S_3<S_2,δ^(18)O为S_1<S_3<S_4<S_2.d-excess在时间尺度上无显著变化,在空间上随河流级别的上升呈下降趋势.脱甲河河水水线方程斜率和截距均略小于当地大气降水线,表明大气降水是河水的主要补给来源.相关分析表明,在季节尺度上,δD和δ^(18)O与水温呈显著负相关(δD:r=-0.92;δ^(18)O:r=-0.88);δ^(18)O与海拔呈显著负相关(r=-0.96);在空间上,δ^(18)O与水温呈显著正相关(r=0.98);δD和δ^(18)O与降水量呈不显著负相关.
The characteristics of hydrogen and oxygen stable isotopes in river is important for regional hydrologic cycle research. To uncover water supply sources in subtropical agricultural basin from a perspective of stable isotopes,field measurements were conducted in four reaches(S1,S2,S3 and S4） of Tuojia River from April to August 2017. We analyzed the spatial and temporal variations in hydrogen and oxygen isotopes and deuterium excess parameters and their relationship with precipitation,altitude and water quality. Results showed that hydrogen and oxygen isotopes and deuterium excess values ranged from-43. 17‰ to-26. 43‰（-35. 50‰ ± 5. 44‰）,-7. 94‰ to-5.70‰（-6.86‰± 0.74‰）,and 16.77‰ to 23. 49‰(19. 39‰ ± 1. 95‰）,respectively. Under the influence of monsoon circulation,hydrogen and oxygen isotopes showed substantial seasonal variation,with spring(δD：-29.88‰±3.31‰; δ^（18）O：-6.18‰±0.57‰） summer(δD：-39.25‰±2.65‰; δ^（18）O：-7.32‰± 0.42‰）. The spatial distribution of hydrogen and oxygen isotopes values increased fluctuantly with the position from the sampling site to the river＇s source,with δD： S1S4S3S2,and δ^（18）O： S1S3 S4 S2. The deuterium excess values had no significant temporal variation,while it spatially increased gradually with the river levels. The slope and intercept of water line in this river were smaller than that of the local meteoric water line,suggesting that precipitation was the primary water source for this river. At the seasonal scale,both δD and δ^（18）O were significantly negatively correlated with water temperature(δD： r =-0.92; δ^（18）O： r =-0.88） and δ^（18）O was negatively correlated with altitude(r =-0.96）. At spatial scale,δ^（18）O had a significantly positive correlation with water temperature. The δD and δ^（18）O had negative correlation with precipitation,but being not statistically significant.
作者
吴红宝
赵强
秦晓波
高清竹
吕成文
WU Hong-bao, ZHAO Qiang1＇2, QIN Xiao-bo, GAO Qing-zhu1, LYU Cheng-wen2(1Institute of Environment and Sustainable Development in Agriculture, Chinese Acade- my of Agricultural Sciences/Key Laboratory of Agricultural Environment, Ministry of Agriculture, Beijing 100081, China ; 2College of Territorial Resources and Tourism, Anhui Normal University, Wuhu 241000, Anhui, China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2018年第5期1461-1469,共9页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(41475129
41775157)
国家发改委CDM基金赠款项目(2014081)资助~~
关键词
氢氧稳定同位素
过量氘
水温
降水
高程
hydrogen and oxygen stable isotopes
deuterium excess
water temperature
precipita-tion
altitude.
