摘要
Sediment cores （-40-100 cm） were collected at 12 locations in the western Bohai Bay, the Haihe River estuary, the Yongding River estuary and the Tianjin Harbor, China, during 24-26 July 2007, and analyzed for ^7Be and ^210pb activities. Due to localized hydrodynamic patterns and frequent disturbance from dredging activities, steady-state sedimentation features were not observed in this study. As demonstrated in the VBe and ^210pb profiles, the temporal and spatial variations of these radionuclides support a non-steady state depositional environment in the study area. By comparing ^7Be and ^210pb inventories in the sediments with those of the atmospheric source, we found that： 1） sediments dredged from the Tianjin Harbor or eroded from nearby estuarine and coastal areas are retained in the western Bohai Bay for relatively short intervals （several months）, as reflected in the relatively high ^7Be inventories in the western Bohai Bay; 2） over the long-term （years to decades）, ^210Pb inventories in the sediments imply that there is a net on-shore transport of sediments, and the sediments are mass-balanced in the entire study area. Overall, our results suggest that the sediments are retained in the estuaries and the western Bohai Bay despite local variability in sediment dynamics and disturbance due to human activities.
沉积核心(锝 ? 0 鈥 ? 00 厘米) 在西方的 Bohai 海湾， Haihe 河河口， Yongding 河河口和天津港口在 12 个地点被收集，中国在 24 鈥 ?2007 年 7 月 6 日期间，并且为 7Be 和 210Pb 活动分析了。由于从挖出活动的局部性的水动力学模式和经常的骚乱，不变的沉积特征没在这研究被观察。是在 7Be 和 210Pb 侧面示威了，这些放射性核种的时间、空间的变化在学习区域支持非稳定的州的 depositional 环境。由大气的来源在沉积把 7Be 和 210Pb 库存与那些作比较，我们发现了那：1 ) 从天津港口挖出或从附近的河口和沿海的区域侵蚀了的沉积为相对短的间隔(几个月) 在西方的 Bohai 海湾被保留，在西方的 Bohai 海湾在相对高的 7Be 库存思考了；2 ) 在上长期(到十年的年) ，在沉积的 210Pb 库存暗示有一张网沉积的向陆的运输，和沉积在全部学习区域是平衡团的。总的来说，我们的结果建议尽管有本地可变性，沉积由于人的活动在沉积动力学和骚乱在河口和西方的 Bohai 海湾被保留。关键词 Bohai 海湾 - 河口 - 沉积 - 沉积运输 - 放射性核种由新泽西海资助支持了(号码 6560-0000， H. 冯) 并且天津科技委员会(号码 06YFGHHZ01500 )
基金
Supported by the New Jersey Sea Grant (No. 6560-0000, H. Feng)
the Tianjin Science and Technology Committee (No. 06YFGHHZ01500)
