长期施氮对土壤肥力及土壤微生物的影响

摘要

Currently, nitrogen fertilizer is the main source of nitrogen in agricultural ecosystems. Long-term application of ni-trogen has a great effect on soil physical and chemical characteristics including soil pH, concentration of organic matter and ni-trogen nutrients, thereby affecting soil microbial biochemical reactions and ecological functions. Studies of nitrogen fertilizer on the soil microflora and their function has become a cutting-edge research on ecological hotspot in recent years. This paper dis-cussed the long-term effects of nitrogen fertilization on soil characteristics, as well as the abundance and community structure of microorganism. At the same time, the soil nitrogen cycle ( nitrogen fixation, nitrification, denitrification ) , carbon cycle ( methane oxidation) related functions flora abundance and structure were also affected, which could lead to soil ecosystem im-balances and barriers to sustainable development of agriculture. From the angle of the soil microorganisms, this paper provided technical basis for rational fertilization system, reducing nitrogen and increasing efficiency of nitrogen fertilizer.%氮肥是农业生态系统活性氮素的主要来源，长期施用氮肥对土壤pH值、有机质含量和氮含量等理化特征产生较大的影响，进而影响土壤微生物的生化反应过程及其生态功能。近年来氮肥对土壤微生物区系及功能菌群的研究已逐渐成为生态学上的一个前沿性研究热点。本文论述了长期施氮对土壤特征的影响，以及其导致的微生物的丰度和菌群结构的变化；同时，土壤中氮循环(固氮、硝化、反硝化)、碳循环(甲烷氧化)相关的功能菌群的丰度和结构也受到影响，进而导致土壤生态系统失衡和障碍农业可持续发展。本文从土壤微生物的角度为我国建立合理施肥制度，实现减施氮肥、提高氮肥效率提供技术依据。