Use of stable isotopes to understand run‐off generation processes in theRedRiverDelta

• DOI: 10.1002/hyp.11296
• Publication Date: 2017-08-05T01:02:44Z
• Authors: Duc Anh Trinh; Minh Thi Nguyet Luu; Quynh Thi Phuong Le
• Keywords: 13. Climate action; 0207 environmental engineering; 02 engineering and technology; 15. Life on land; 01 natural sciences; 6. Clean water; 0105 earth and related environmental sciences

Abstract This paper presents the use of stable isotopes water for hydrological characterization and flow component partitioning in Red River Delta (RRD), downstream section River. Water samples were collected monthly during 2015 from mainstream river its right bank tributaries flowing through RRD. In general, δ 18 O 2 H signatures depleted summer–autumn (May–October) elevated winter–spring (November–April), displaying seasonal variation response to regional monsoon air mass contest. The Pacific equatorial–maritime dominates summer northern Asia continental controls winter. Results show that RRD stems solely local sources is completely separated arriving upstream subbasins. separation due extensive management (e.g., dykes dams) purposes irrigation inundation prevention. Mainstream compositions range −10.58 −73.74‰ −6.80 −43.40‰, respectively, corresponding ranges inside −9.35 −64.27‰ −2.09 −15.80‰. A combination data analysis simulation confirms role hydropower reservoirs retaining mixing water. experienced strong evaporation characterized by d‐excess values, becoming negative summer. On other hand, main stream has values around 10‰, indicating moderate evaporation. Hydrograph shows subbasins, groundwater fraction composition, especially low regimes. Inside RRD, receives dry season, whereas replenishment occurs rainy season. Annual obtained this hydrograph computation was about 6.3% catchment discharge, same order as deduced difference between subbasin precipitation discharge values. study necessity re‐evaluate empirical approaches large hydrology assessment schemes, context climate change.