地理研究 ›› 2017, Vol. 36 ›› Issue (2): 361-372.doi: 10.11821/dlyj201702013

• 研究论文 • 上一篇    下一篇

北京东南郊再生水灌区不同水体氢氧同位素特征及成因

王亚俊1,2,3(), 宋献方1,2(), 马英1, 张应华1, 郑凡东4, 杨丽虎1, 卜红梅1   

  1. 1.中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室,北京 100101
    2.中国科学院大学资源与环境学院,北京 100049
    3.中国科学院大学中丹学院,北京 100190
    4.北京市水科学技术研究院,北京 100048
  • 收稿日期:2016-09-07 修回日期:2016-12-03 出版日期:2017-02-20 发布日期:2017-03-07
  • 作者简介:

    作者简介:王亚俊(1987- ),女,山西朔州人,博士研究生,主要从事流域水循环与水环境研究。E-mail:wang_yajun2009@163.com

  • 基金资助:
    中国科学院地理科学与资源研究所战略科技计划项目(2012ZD003)

Characterizing the hydrogen and oxygen isotopic compositions of different waters at reclaimed water irrigated district in southeast suburb of Beijing

Yajun WANG1,2,3(), Xianfang SONG1,2(), Ying MA1, Yinghua ZHANG1, Fandong ZHENG4, Lihu YANG1, Hongmei BU1   

  1. 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Beijing 100101, China
    2. College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
    3. Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100190, China
    4. Beijing Water Science & Technology Institute, Beijing 100048, China
  • Received:2016-09-07 Revised:2016-12-03 Online:2017-02-20 Published:2017-03-07

摘要:

再生水、地表水和地下水的氢氧同位素特征是研究水体转化及水循环过程的重要基础性工作。为了分析北京市东南郊再生水灌区内再生水、地表水和不同深度地下水的氢氧同位素特征及成因,分别于2014年和2015年采集并测定了灌区内不同水体的氢氧同位素组成。结果表明:再生水的δ18O和δD范围分别为-7.4‰~-6.4‰和-56‰~-52‰;地表水的δ18O和δD范围分别为-8.2‰~-4.8‰和-64‰~-49‰;地下水的δ18O和δD范围分别为-13.2‰~-6.0‰和-92‰~-52‰。再生水经使用和处理后,氢氧稳定同位素富集。地表水的氢氧同位素沿河渠流向呈富集趋势,但在个别点存在氢氧同位素贫化的地下水输入。深层地下水氢氧同位素组成显著小于浅层地下水,300 m和150 m左右的深层地下水氢氧同位素最为贫化,为寒冷气候条件下降水入渗补给;浅层地下水主要受到再生水、降水、灌溉水等水体垂直入渗补给;而河渠附近10 m范围内的浅层地下水主要由河渠水补给,个别监测井水还受到地下水的侧向补给。

关键词: 再生水灌区, 氢氧同位素, 地表水, 地下水, 北京

Abstract:

Characteristics of hydrogen and oxygen isotope of reclaimed water, surface water and groundwater are essential to recognize hydraulic connection and regional hydrologic cycle. In order to obtain stable isotope (δ18O, δD) characteristics and detect causes of differences among different water bodies (precipitation, reclaimed water, surface water and groundwater in different depths), field investigation and water samples collection were conducted separately in 2014 and 2015 at reclaimed water irrigation district located in the southeast suburb of Beijing. The results showed that: local meteoric water line of Beijing was expressed with the function of δD=7.27 δ18O+2.43 (R2=0.93,n=198) which was well used as isotopic baseline. δ18O value in reclaimed water ranged from -7.4‰ to -6.4‰ and δD ranged from -56‰ to -52‰. Isotopic composition of surface water ranged from -8.2‰ to -4.8‰ in δ18O and from -64‰ to -49‰ in δD. As for groundwater, the wide range in δ18O varied from -13.2‰ to -6‰ and δD ranged from -92‰ to -52‰ respectively. Reclaimed water and surface water carried heavier isotope composition than groundwater, with a descending order of surface water > reclaimed water > groundwater in δ18O and reclaimed water > surface water > groundwater in δD. After the fresh water being used and treated, reclaimed water was enriched in heavy hydrogen and oxygen isotope due to evaporation fractionation. Generally, the heavy isotope becomes enriched gradually along the river flow, while the sudden drop phenomena could be ascribed to entrance of depleted isotope groundwater. On account of slow circulating, the wetland water recharged by the Hanhe River had undergone strongest evaporation which was heaviest isotopic concentration in all the samples. Generally, the isotopic composition of deep groundwater (depth >80 m) was much more depleted than that of shallow groundwater (depth <80 m). The most depleted isotopic value of groundwater at depths of 300 m and 150 m are recharged by the infiltration of precipitation that occurred in colder paleoclimate rather than in modern climate, and no influence occured from reclaimed water. Shallow groundwater from monitoring wells which are located 10 m away from the waterways was dramatically recharged by river and canal water nearby, however lateral flow of depleted groundwater penetrating to some wells adjacent river channel was observed. It is indicated that vertical infiltration of reclaimed water, precipitation and irrigation water with groundwater play vital roles in shallow groundwater recharge at reclaimed water irrigation district.

Key words: reclaimed water irrigation district, hydrogen and oxygen stable isotope, surface water, groundwater, Beijing