Proglacial river sediment fluxes in the southeastern Tibetan Plateau: Mingyong Glacier in the Upper Mekong River
Proglacial river sediment fluxes in the southeastern Tibetan Plateau: Mingyong Glacier in the Upper Mekong River
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DOI：
10.1002/hyp.14751
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发表时间：
2022-10
影响因子：
3.2
通讯作者：
Xixi Lu;Ting Zhang;Boey Lai Hsia;Dongfeng Li;Heather Fair;H. Niu;S. D. X. Chua;Li Li-Li;Shaojuan Li
中科院分区：
文献类型：
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作者：
Xixi Lu;Ting Zhang;Boey Lai Hsia;Dongfeng Li;Heather Fair;H. Niu;S. D. X. Chua;Li Li-Li;Shaojuan Li
冰川和前冰川侵蚀是流域重要的沉积物来源。青藏高原许多冰川的退缩对下游流域的淡水供应和沉积物动态具有重要影响。尽管这些流域的水和沉积物动力学很重要，但由于交通不便和环境具有挑战性，现有对青藏高原冰川流域悬浮沉积物通量的量化受到限制。本研究介绍了2013年8月至2017年7月对中国西南部云南省明永冰川流域的流量和悬浮泥沙通量的现场调查结果。结果表明，流量和悬浮泥沙的变化具有很强的季节性。平均悬浮泥沙浓度变化较大，为69±45； 119±104； 2013 年、2015 年和 2016 年分别为 94 ± 97 mg/L。我们估计，明永流域的产沙量变化很大，从2013年的1104吨/平方公里/年到2016年的2281吨/平方公里/年，其中每年总输沙量的65%~78%发生在夏季（6月至8月）。沉积物产量的这些年度变化很大程度上归因于降水模式和极端融化事件。这项研究提供了一个基准数据集，可用于进一步研究气候变化对青藏高原冰川流域沉积物动态的影响。随后，这项研究帮助我们更好地了解冰川源头集水区对湄公河上游沉积物供应的增加。
Glacial and proglacial erosion are important sediment sources in river basins. The retreat of many glaciers on the Tibetan Plateau has important implications on the supply of fresh water and sediment dynamics for downstream river basins. Despite the importance of water and sediment dynamics at these catchments, existing quantification of suspended sediment fluxes from glacial catchments on the Tibetan Plateau is limited due to poor accessibility and challenging environments. This study presents the results of in‐situ investigations of water discharge and suspended sediment fluxes from the Mingyong Glacier catchment in Yunnan, Southwest China, between August 2013 and July 2017. The results show that the variation in water discharge and suspended sediment was highly seasonal. The variation of average suspended sediment concentration was large—69 ± 45; 119 ± 104; and 94 ± 97 mg/L in 2013, 2015, and 2016, respectively. We estimate that the sediment yield from the Mingyong catchment was highly variable ranging from 1104 t/km2/year in 2013 to 2281 t/km2/year in 2016, with 65%–78% of the total annual sediment load occurring during the summer (June to August). These annual variations in sediment yield can be attributed largely to precipitation patterns and extreme melting events. This study has provided a benchmark dataset that can be used for further works that investigate the impact of climate change on sediment dynamics in glacierized catchments in the Tibetan Plateau. Subsequently, the study helps us to better understand the increasing sediment supply to the Upper Mekong River from glacierized headwater catchments.