【摘要】 选择三江平原典型草甸小叶章湿地土壤(草甸沼泽土)为研究对象,采用厌氧淹水培养法,研究了不同土层的反硝化率、反硝化能力及反硝化速率。结果表明,不同土层的反硝化率均随培养时间延长而增加,0～30cm土层的反硝化率较高,30cm以下土层较低且相近;不同土层的氮损失贡献率在不同阶段具有明显的时空分异特征,0～30cm土层的氮损失贡献率较高,介于52.39%和57.91%之间;不同土层的反硝化速率与培养时间均符合一阶指数衰减模型(R2≥0.97),上层土壤的反硝化速率明显高于下层土壤。不同土层的反硝化率和反硝化速率与土壤理化性质密切相关,反硝化细菌的剖面分布可能对其具有重要影响。图3,表4,参24。更多还原

【Abstract】 The typical Calamagrostis angustifolia wetland soil (meadow marsh soil ) was selected as study objects,and the denitrification ratios,capacities and rates of different soil layers were studied by anaerobic submerged incubation method. Results showed that the denitrification ratios of different soil layers increased as the lapse of incubation time,and the values of 0-30cm layers were much higher,while those of 30cm-80cm layers were much lower and approximate. In different incubation phases,the nitrogen loss percentages of different soil layers had significantly temporal and spatial variation characteristics. Comparatively,the nitrogen loss percentages of 0- 30cm layers were much higher,and the values were between 52. 39% and 57. 91%. The relationships between denitrification rates of different soil layers and incubation times accorded with first-order exponential decay models (R2≥0. 97). In addition,the denitrification rates of upper soil layers were much higher than those of subsoil layers. The denitrification activities and rates were mainly correlated with soil physical or chemical properties,and the profile distribution of denitrifying bacteria might have significant effects on them.更多还原