【摘要】 选择三江平原不同水分带上的小叶樟湿地为研究对象,对比研究了不同类型土壤(草甸沼泽土和腐殖质沼泽土)中各形态氮在不同时期的剖面分布特征。结果表明,草甸沼泽土和腐殖质沼泽土的剖面特征以及不同时期各形态氮的垂直分布特征均存在不同程度差异,二者全氮、有机氮和碱解氮的垂直分布特征主要受制于土壤有机质的分布,硝态氮和铵态氮主要与不同时期土壤水分条件差异及其引起的不同质地土层硝态氮的垂直淋失和对铵态氮的吸附程度有关;两种土壤的各形态氮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氮分布的主导因素差异有关;两种土壤的氮储量及其分布状况存在较大差异,前者0～80cm土层的氮储量(1.94kgm-2)明显高于后者(1.38kgm-2),前者的氮储量主要集中于0～40cm土层(1.06kgm-2,占76.36%),后者则主要集中于0～30cm土层(1.15kgm-2,占59.10%)。更多还原

【Abstract】 The Calamagrostis angustifolia wetlands,located in different water gradient,were selected as study objects,and the profile distribution characteristics of nitrogen(N) formed in meadow marsh soil and humus marsh soil in different periods were contrastively studied.Results showed that the profile characteristics and N vertical distribution characteristics of the two types of soils in different periods had some differences.The vertical distribution characteristics of total N,organic N and alkaline hydrolysis N were mainly controlled by the distribution of soil organic matter,while those of nitrate N(NO3--N) and ammonium N(NH4+-N) were mainly correlated with the differences of soil water conditions in different period.The NO3--N vertical leaching and soil NH4+-N adsorption were the direct reasons to cause the distribution of NO3--N and NH4+-N in different periods.The N forms in the two types of soils in different periods had significantly vertical variability,which were mainly correlated with the differences of dominant factors,affecting N distribution,in upper soil or subsoil layers.The N storages and their distribution statuses of meadow marsh soil and humus marsh soil had significantly different,and the N storage of the former(1.94 kg m-2) was much higher that that of the latter(1.38 kg m-2).In addition,the N storage of the former mainly distributed in 0-40cm layers(1.06 kg m-2,accounted for 76.36%),while that of the latter mainly distributed in 0-30 cm layers(1.15 kg m-2,accounted for 59.10%).更多还原