Effects of Nitrogen Fertilization on Litter and Soil Decomposition: Microbial Biomass

The influence of inorganic nitrogen (N) inputs on decomposition is poorly understood. Some prior studies suggest that N may reduce the decomposition of substrates with high concentrations of lignin via inhibitory effects on the activity of lignin-degrading enzymes, although such inhibition has not always been demonstrated. The purpose of E145 was to study the effects of nitrogen (N) addition on decomposition of seven substrates ranging in initial lignin concentrations (from 7.4 - 25.6%) over five years in eight different grassland and forest sites in central Minnesota.

无机氮（inorganic nitrogen）输入对底物分解过程的影响目前尚未得到充分阐明。既往部分研究表明，氮可通过抑制木质素降解酶的活性，降低高木质素浓度底物的分解速率，但此类抑制效应并非总能得到证实。E145实验旨在探究氮素添加对初始木质素浓度介于7.4%至25.6%之间的7种底物分解过程的影响，实验在美国明尼苏达州中部的8处不同草原与森林样地开展，周期为5年。