研究分析了长江口柱状沉积物中氮的赋存形态,并结合沉积速率和有机碳含量分析了氮的迁移转化特征和有机质来源.研究结果表明,有机物与硫化物结合态氮(OSF-N)是柱状样可转化形态氮中的主要赋存形态,碳酸盐结合态氮(CF-N)含量最低；位于长江口122°E附近测点的各形态氮的垂直分布与122.6°E附近测点的差异明显,受水动力条件和沉积速率等因素影响,122.6°E附近测点的有机氮降解速率常数和各形态氮的埋藏通量均高于122°E附近测点；长江口柱状沉积物中有机氮降解主要发生在沉积物表层和次表层；OC/TN值的垂直分布变化幅度较大,陆源输入均大于70％.%Total nitrogen and its forms in the core sediments from Changjiang River Estuary were studied with sequential extraction method. And combined with the deposition rate and the organic carbon content, the characteristics of its migration and transformation and the sources of organic carbon were also studied. The results show that OSF-N is the main form of transferable nitrogen, and CF-N content is the lowest of the transferable nitrogen in the core sediments. There are evident differences in the vertical distribution of different nitrogen forms in the core sediments of SH3111 station(at 31°N, 122°E) from that in SH3110 station (31°N, 122. 6°E). Affected by the hydrodynamics and the deposition rate, the values of the degradation rate constant of the organic nitrogen and the burial flux of different forms of nitrogen at the SH3110 station are higher than those at the SH3111 station. Degradation of the organic nitrogen occurred mainly in the surface and sub-surface layers of the sediment and the vertical distribution of the OC/TN ratios varies greatly, showing different depositional conditions. The proportions of terrigenous carbon are higher than 70%.
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