State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, PR China.
State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200241, PR China.
Chemosphere. 2021 Jan;263:127896. doi: 10.1016/j.chemosphere.2020.127896. Epub 2020 Aug 15.
Particle-reactive radionuclides are useful for tracing sediment dynamics in marginal seas. We collected a suite of surface sediment samples in May 2014 from the Bohai Sea (BS) and Northern Yellow Sea (NYS) to observe the spatial distribution of Plutonium (Pu) isotopes and Pb activities. Pu activities ranged from 0.001 to 0.288 and 0.040-0.269 Bq kg in BS and NYS surface sediments, respectively. Pb shows a significant correlation with Pu (r = 0.84, p < 0.01) that suggested these two nuclides were scavenged to the same grade. Pu/Pu atom ratios in BS (0.173-0.256) and NYS (0.196-0.275) were slightly higher than the global fallout value of 0.18 and lower than the Pacific Proving Ground (PPG) value of 0.36, indicating that some fraction of Pu originating from the PPG was capable of being transported to the BS and NYS. Mass balance results showed that 41% of Pu (8.9 × 10 Bq yr) and 18% of Pb (2.4 × 10 Bq yr) in the NYS originated in the oceanic input. In the BS, 63% of Pb originated from atmospheric deposition and 84% of Pu originated from riverine input. Using Pu and Pb as tracers, we estimate that (1.8-2.6) × 10 t yr and (3.6-3.8) × 10 t yr of sedimentary particles could be transported from the BS to the NYS and from the NYS to the Southern Yellow Sea, respectively. Furthermore, the Ra/U activity ratio distribution suggested that sedimentary particles derived from the Yellow River could be transported to the middle of the BS and coastal areas of the NYS.
颗粒反应性放射性核素可用于追踪边缘海的沉积物动力学。我们于 2014 年 5 月在渤海（BS）和北黄海（NYS）收集了一系列表层沉积物样本，以观察钚同位素和 Pb 活性的空间分布。BS 和 NYS 表层沉积物中的 Pu 活性分别为 0.001 至 0.288 和 0.040 至 0.269 Bq kg。Pb 与 Pu 呈显著相关（r = 0.84，p < 0.01），表明这两种核素被同等级地捕获。BS（0.173-0.256）和 NYS（0.196-0.275）中的 Pu/Pu 原子比略高于全球沉降值 0.18，低于太平洋试验场（PPG）值 0.36，表明部分来自 PPG 的 Pu 能够运移到 BS 和 NYS。质量平衡结果表明，NYS 中 41%的 Pu（8.9×10 Bq yr）和 18%的 Pb（2.4×10 Bq yr）来源于海洋输入。在 BS 中，63%的 Pb 来自大气沉积，84%的 Pu 来自河流输入。使用 Pu 和 Pb 作为示踪剂，我们估计分别有（1.8-2.6）×10 t yr 和（3.6-3.8）×10 t yr 的沉积物颗粒从 BS 运移到 NYS，从 NYS 运移到南黄海。此外，Ra/U 活度比分布表明，来自黄河的沉积物颗粒可运移到 BS 中部和 NYS 沿海地区。
