欢迎访问《生态学杂志》官方网站,今天是 分享到:

生态学杂志

• 研究论文 • 上一篇    下一篇

筑坝拦截对梯级水库水体氢氧同位素组成的影响:以嘉陵江为例

张俊1,崔高仰2,3,李亲凯1,黄俊2,3,陶月乐1,杨梦迪1,李斯奇1,李晓东1*   

  1. (1天津大学表层地球系统科学研究院, 天津 300072;2中国科学院地球化学研究所环境地球化学国家重点实验室, 贵阳 550081;3中国科学院大学, 北京 100049)
  • 出版日期:2018-03-10 发布日期:2018-03-10

Effects of dam interception on hydrogen and oxygen isotope compositions in cascade reservoirs: A case of Jialing River.

ZHANG Jun1, CUI Gao-yang2,3, LI Qin-kai1, HUANG Jun2,3, TAO Yue-le1, YANG Meng-di1, LI Si-qi1, LI Xiao-dong1*   

  1. (1Institute of SurfaceEarth System Science, Tianjin University, Tianjin 300072, China; 2State Key Laboratory of EnvironmentalGeochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; 3University of Chinese Academy of Sciences, Beijing 100049, China).
  • Online:2018-03-10 Published:2018-03-10

摘要: 筑坝拦截导致河流天然属性的改变,进而影响了相关流域水循环过程。本研究以嘉陵江流域4座梯级水库为对象,于2016年1、4、7、10月份采集水样,分析水体氢氧同位素组成,以期通过氢氧同位素组成的时空变化特征来探讨大坝拦截对于流域水循环的影响。结果表明,表层水体的δ18O和δD沿河流流向上总体有偏正的趋势,应该是受纬度效应及筑坝拦截作用的共同影响;研究区水库库区水体在1、10月的δ18O均值较4、7月偏正,是降雨量与降雨来源不同导致的结果;具有热分层特征的水库(亭子口水库)在夏季分层期的18O值变化范围比其他季节大,其他水库则没有这种特点,另外,水库分层还会使得库区表层水与下泄水的氢氧同位素值出现较大差异;梯级水库的存在使得流域蒸发作用强烈,导致河水氢氧同位素组成大大偏离当地大气降水线,研究区夏季(7月)的蒸发作用最强,春季(4月)次之,冬秋季(1、10月)最弱。

关键词: 果园生草, 土壤养分, 经济效益, 土壤酶活性

Abstract:

River damming alters natural attributes of rivers, with consequences on water cycle in the river catchment. In this study, water samples including stratified water from four cascadereservoirs in the Jialing River basin were collected in January, April, July, and October in 2016. The hydrogen and oxygen isotopic compositions and their spatial and temporal variations wereanalyzed to assess the impacts of dam interception on water cycle in the river basin. The results showed that the δ18O and δD values of the surface water were generally turning positive along with the flow path due to the latitude effect and the dam interception. The δ18O values of the water samples were more positive in January and October than those in April and July, which should be resulted from the variations in the amount and sources of precipitation. In the summer stratification period, the range of18O value in the reservoir with thermal stratification (Tingzikou reservoir) was larger than that in other seasons. In contrast, it was not the case in other reservoirs. Moreover, reservoir stratification led to divergence in hydrogen and oxygen isotopic compositions between the discharged water and the surface water near dam. The existence of cascade reservoirs enhanced watershed evaporation, which might be responsible for the greater deviation of thehydrogen and oxygen isotope compositions of the river water from the local meteoric water line. The evaporation in the summer (July) was the strongest in the study area, followed by the spring (April) and the weakest in the winter and autumn (January and October).
 

Key words: planting white clover in orchard, soil enzyme activity, economical benefit, soil nutrient