中文摘要：

选择位于黄河口滨岸中潮滩和低潮滩上的翅碱蓬湿地为研究对象,对比研究了湿地土壤碳、氮在不同时期的垂直分布特征。结果表明,两种湿地土壤的TC、TN、NO3--N、NH4＋-N和C/N在不同时期的垂直分布特征均存在不同程度差异,TC、TN的垂直分布特征主要受制于土壤有机质的分布和潮汐影响状况,NO3--N、NH4＋-N主要与不同时期土壤水分条件差异及其引起的不同土层硝态氮的垂直淋失和对铵态氮的吸附程度有关,C/N的差异主要与其受陆源影响程度有关;两种湿地土壤TC、TN、NO3--N、NH4＋-N和C/N在不同时期均存在较高的垂直变异性,原因主要与上下层土壤影响碳、氮分布的主导因素差异有关;两种湿地土壤的碳、氮储量及分布状况均存在较大差异,低潮滩湿地土壤0~60 cm土层的碳、氮储量（3.9413 kg m-2和0.4041 kg m-2）均高于中潮滩湿地土壤（3.5964 kg m-2和0.3639 kg m-2）,且除40~50 cm、50~60 cm土层外,其它土层的碳、氮储量分别比中潮滩湿地土壤的相应土层高2.87%~51.01%和2.52%~3.89%。

英文摘要：

The Suaeda salsa marshes in middle tidal flat（MTF） and low tidal flat（LTF） of the Yellow River estuary,were selected as study objects,and the profile distribution characteristics of carbon（C） and nitrogen（N） in different periods were contrastively studied.Results showed that the vertical distribution characteristics of TC,TN,NO3--N,NH4＋-N and C/N in the two types of soil in different periods had some differences.The vertical distribution characteristics of TC and TN were mainly controlled by the distribution of soil organic matter and the effects of tide,while those of NO3--N and NH4＋-N were mainly correlated with the differences of soil water condition in different periods.The NO3--N vertical leaching and soil NH4＋-N adsorption were the direct reasons for the distribution of NO3--N and NH4＋-N in different periods.The C/N in different soils was related to the effects of terrestrial sources.The TC,TN,NO3--N,NH4＋-N and C/N in the two types of soil in different periods had significantly vertical variability,which were mainly correlated with the differences of dominant factors affecting the C and N distributions in topsoil and subsoil.The C and N stocks and their distribution statuses in MTF and LTF soils had significantly differences,and the C and N stocks of the latter（3.9413 kg m-2 and 0.4041 kg m-2） were much higher than those of the former（3.5964 kg m-2 and 0.3639 kg m-2）.Except for the 40-50 cm and 50-60 cm layers,the C and N stocks in LTF soil in different layers were separately 2.87%-51.01% and 2.52%-3.89% higher than those in MTF soil.