Hanyang University, ERICA campus, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan-si, Gyeonggi-do 15588, South Korea.
KOPRI Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon 21990, South Korea.
Mar Pollut Bull. 2021 Jul;168:112383. doi: 10.1016/j.marpolbul.2021.112383. Epub 2021 Apr 30.
We investigated a sediment core collected from the Geum Estuary through sedimentological and geochemical analyses. Three lithological units were classified based on sedimentological characteristics. Unit 1 and Unit 3 were geochemically distinct, while Unit 2 was the transitional phase between them. The geochemical results suggest that the contribution of terrestrial organic carbon (OC) to the sedimentary OC pool in the coarse-grained Unit 1 was lesser than that of fine-grained Unit 3. The excess activity (Pb) and the sedimentation rate indicate that Unit 1 corresponded to 1977 Common Era (CE). Since the first dam construction on the Geum River began in 1975 CE, the deposition of Unit 1 in the Geum Estuary is likely associated with river impoundments, which reduce the delivery of fine-grained sediment and terrestrial OC to the estuary. This study highlights the role of river impoundments in altering the sedimentary OC and thus the sedimentary environment in the estuary.
我们通过沉积学和地球化学分析研究了从 Geum 河口采集的沉积物岩芯。根据沉积学特征，将三个岩性单元进行了分类。单元 1 和单元 3 在地球化学上有明显的区别，而单元 2 则是它们之间的过渡阶段。地球化学结果表明，粗粒单元 1 中陆地有机碳 (OC) 对沉积 OC 库的贡献小于细粒单元 3。过剩活性 (Pb) 和沉积速率表明，单元 1 对应于公元 1977 年 (CE)。自 1975 年开始在 Geum 河上建造第一座大坝以来，Geum 河口单元 1 的沉积可能与河坝有关，河坝减少了细粒沉积物和陆地 OC 向河口的输送。本研究强调了河坝在改变河口沉积 OC 从而改变沉积环境方面的作用。
