渤海南部沉积物中的活性铁及氧化还原环境

ACTIVE IRON AND REDOX ENVIRONMENT OF SEDIMENTS IN THE SOUTHERN BOHAI SEA

研究了渤海南部沉积物中的活性铁、沉积物粒度、氧化还原环境及其关系。结果表明 ,沉积物中的活性铁与沉积物颗粒度大小关系不大 ,河流输入物对沉积物活性铁浓度有重要影响 ,沉积物中活性铁与其氧化还原环境有密切关系。

This paper emphasized on active iron, sediment grain size, redox environment and their relations in sediments of the southern Bohai Sea. The main results are as follows: There is no relation between the concentrations of active iron and sediment grain size, but sediment grain size vs. Fe 3+ /Fe 2+ vary in positive correlation, i.e. the finer the sediment grain size, the smaller the Fe 3+ /Fe 2+ ratio. The distributions of acitve iron near estuary are very complicated . The concentrations of active Fe 3+ in sediments are low, but in general those of active Fe 2+ are high near estuary. The behaviours of acitve iron near Luanhe River estuary and near Huanghe River estuary are different, and the former′s active iron is low, the later′s active iron is high, which are controlled by input matter. The Bohai Bay is a region of high active iron. The active Fe 3+ tends to decrease and the active Fe 2+ tends to increse on the vertical profiles of sediments. There is a close relation between active iron and redox environment in sediments. The redox interface of sediments in the southern Bohai Sea is located in ROD=15, Eh=100 mV, Fe 3+ =3.3 mg/g,Fe 2+ =1.82 mg/g and Fe 3+ /Fe 2+ =0.55.