土壤粗有机质的研究进展

土壤粗有机质是土壤中较为活跃的组分， 其密度组分对土壤有机质总矿化量有着重要贡 献， 可以作为评价管理措施转变引起土壤有机质短期变化的敏感性指标。分别介绍了按照不同的 物理分组方法划分的土壤有机质各物理组分的概念、土壤粗有机质及其分离方法， 探讨了影响土 壤粗有机质数量的主要因素( 管理措施、土地利用方式、土壤质地和气候条件) 和当前在研究土壤 粗有机质过程中存在的问题: ( 1) 各影响因素引起的土壤有机质变化的机制还不确定; ( 2) 土壤粗 有机质的分离方法还有待深入研究; ( 3) 粗有机质对土壤有机氮矿化的贡献认识还存在分歧。指 出探求更好的土壤粗有机质的分离方法和粗有机质对各影响因素的响应机制， 揭示土壤粗有机 质对土壤氮矿化的贡献是今后的主要研究方向。

Review on Study of the Soil Macro- organic Matter

Soil macro-organic matter(MOM) with a rapid turnover rate plays a dominant role in soil nutrient dynamics,especially soil nitrogen.MOM is a significant component of light organic matter in soils.It can be a sensitive index to reflect the short-term effects of the management on soil organic matter.This paper reviews the concepts of various soil organic matter(SOM) fractions by different physical fractionations,details the fractionation methods for soil macro-organic matter(MOM),discusses the factors which have influences on the content of the soil MOM,factors which include management,land use,soil texture and climate.In the end,this paper points out the existing problems about the study of MOM: (1)The dynamic mechanism of soil organic matter is still puzzling.(2)The procedure for the separation of the soil MOM fraction needs to be studied further.(3)Many researchers' opinions diverge from each other on the contribution of MOM to soil nitrogen mineralization. In future,the study should focus on the mechanism of MOM responding to affecting factors,separating methods and the contribution of MOM to soil nitrogen mineralization.