洱海流域农田土壤氮素的矿化及其影响因素

采用好氧间歇淋洗培养法,对洱海流域内的农田、菜地土壤样品培养2周,研究土壤氮的矿化及其影响因素.结果表明,表层土壤2周氮矿化量平均为65.54mg/kg.不同农田利用方式下,表层土壤氮矿化量的平均值为露地菜田粮田大蒜田.土壤氮素矿化以硝态氮为主,且随着土壤深度的增加而降低.土壤氮矿化同全氮、有机质含量呈明显的正相关关系,与pH值呈负相关;氮矿化与无机氮含量、C/N之间无显著关系.全氮、有机质和pH值是影响该流域农田土壤矿化的主要因子.

Nitrogen mineralization and its influence factors in the farmland soils of Erhai Lake Basin

The characteristics and influence factors of nitrogen(N) mineralization in vegetable soils and grain soils of Erhai Lake region of China were studied using a two-week anaerobic incubation method.The average rate of soil N mineralization during the two weeks was 65.54 mg/kg.The soil N mineralization trend under different cropping patterns was as follows: vegetable fields>grain fields>garlic fields.The quantity of mineralization,which included mostly NO3--N decreased with the depth of the soil samples.The min...