微量元素锰对耕作层氮元素的迁移规律研究

Research on Effects of Manganese on Nitrogen Transport in Soil Columns

摘要: 研究微量元素锰的含量对耕作层氮元素的迁移规律，以便优化化肥养分在土壤中的传递过程。基于实验室土柱模拟，采用不同含量的微量元素锰与微生物菌剂配施处理，通过测定5 cm与15 cm处速效氮的含量来研究氮元素的迁移规律。结果表明：微生物菌剂和肥料混施，固氮菌能够将大气和土壤空气中的N₂还原为NH₃，最终转化为NH⁺₄ -N，增加了土壤中速效氮的含量。所以微生物菌剂和肥料混施不但有利于土壤中氮素的增加，而且有利于氮素的向下迁移。锰元素与氮素的循环有着密切的关系。在本实验中，15 cm处加入锰元素的各组的速效氮含量均高于空白组，p<0.001具有显著性差异。最佳锰离子浓度为C/Mn = 40。氮元素在好氧环境下，适量浓度的还原性锰离子会参与氨氮的氧化过程，即把NH⁺₄-N氧化成NO^-₃-N或NO^-₂-N，则氮素更容易向下迁移。

Abstract: Based on the laboratory soil column simulation, we studied the effects of different manganese contents on migration rules of nitrogen element in the cultivated layer to optimize the transfer process of fertilizer nutrient in soil by using the different content of trace elements manganese and microbial agents, and the 5 cm and 15 cm available nitrogen content were measured to study the migration regularity of nitrogen element. The results showed that with mixed microbial agents and fertilizer, nitrogen-fixing bacteria reduced N₂ to NH₃, eventually NH⁺₄-N, which increased the content of available nitrogen in the soil. So mixed microbial agents and fertilizer were beneficial for the increase of nitrogen in the soil as well as the downstream migration of nitrogen. Manganese was closely related to the cycle of nitrogen. In this experiment, the various groups of the manganese elements were higher than the non-manganese elements group at the 15 cm section, p < 0.001 which had statistical significance. And the optimum manganese ion concentration was C/Mn = 40. When nitrogen was in aerobic environment, moderate concentration of reducible manganese ion would participate in the process of ammonia nitrogen oxide, which oxidized NH⁺₄-N toNO^-₃-N or NO^-₂-N, and nitrogen migrating down more easily.