State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing 100083, China; School of Water Resources & Environment, China University of Geosciences, Beijing 100083, China.
State Key Laboratory of Biogeology and Environmental Geology & MOE Key Laboratory of Groundwater Circulation and Environment Evolution, China University of Geosciences, Beijing 100083, China; School of Water Resources & Environment, China University of Geosciences, Beijing 100083, China.
Sci Total Environ. 2019 May 20;666:298-307. doi: 10.1016/j.scitotenv.2019.02.245. Epub 2019 Feb 17.
We collected 3275 sets of δD and δO and 1451 C data of groundwater in 14 basins or plains in the Northern China from the published sources in an attempt to investigate the isotopic characteristics of groundwater and their possible link with groundwater recharge and modern and past climate conditions in regional scales. The results showed that the deuterium excess of groundwater in the Monsoon regions were generally lower than that in the Westerly regions in the Northern China, reflecting the influences of different vapor sources and transmission modes. The δD and δO in groundwater lied closely to the Asian summer monsoon limit (ASML) were affected by both the Asian monsoon and Westerlies. The δD and δO of groundwater exhibited obvious latitude effect in the monsoon region, while it seemed to be dominated by the continental and elevation effects in the Westerly region both in the late Pleistocene and the Holocene. Based on the isotopic proxy records of climates, the depletion in O and D of the groundwater recharged in last glacial period in the late Pleistocene was observed which indicated that it was cooler especially in the Last Glacial Maximum (LGM), while the O and D were enriched in groundwater recharged in the Holocene. The transition from the late Pleistocene to Holocene was characterized by higher frequency fluctuation of δO in the groundwater, probably suggesting that the climatic conditions were unstable. The groundwater recharge could be roughly divided into three main periods under relative warm and humid climates. The variation of regional climate was one of the driving forces for the recharge and regeneration of groundwater. Our results may enhance the understanding of groundwater recharge and its connection with the climate changes in the regional scales.
我们从已发表的文献中收集了中国北方 14 个盆地或平原的 3275 组地下水 δD 和 δO 值和 1451C 值，试图调查地下水的同位素特征及其与地下水补给以及区域尺度现代和过去气候条件的可能联系。结果表明，中国北方季风区地下水的氘过剩值普遍低于西风区，反映了不同水汽源和传输方式的影响。靠近亚洲夏季风限（ASML）的地下水 δD 和 δO 值同时受到亚洲季风和西风的影响。在季风区，地下水的 δD 和 δO 值表现出明显的纬度效应，而在晚更新世和全新世，西风区似乎主要受大陆和海拔效应的控制。根据气候同位素示踪记录，晚更新世末次冰期补给的地下水的 O 和 D 同位素明显亏损，表明当时气候较冷，特别是在末次冰盛期（LGM），而全新世补给的地下水的 O 和 D 同位素则富集。晚更新世向全新世的转变特征是地下水 δO 的高频波动，可能表明气候条件不稳定。在相对温暖和潮湿的气候条件下，地下水补给可大致分为三个主要时期。区域气候变化是地下水补给和再生的驱动力之一。我们的研究结果可能有助于提高对区域尺度地下水补给及其与气候变化关系的认识。
