溶解性有机质在红壤水稻土碳氮转化中的作用  

Influence of dissolved organic matter on transformations of carbon and nitrogen in Paddy soils in subtropical China

作　　者：韩成卫[1] 李忠佩[1] 刘丽[1] 车玉萍[1] 

机构地区：[1]中国科学院南京土壤研究所//土壤与农业可持续发展国家重点实验室

出　　处：《生态环境》2006年第6期1300-1304,共5页Ecology and Environmnet

基　　金：国家自然科学基金项目(40471066);国家重点基础研究发展计划"973"项目(2005CB121108)

摘　　要：溶解性有机质(DOM)是土壤中活跃的C、N库,在土壤有机质分解转化等过程中有着重要的作用。但其在水田土壤C、N转化过程中究竟起多大作用仍不明确。本研究采用室内恒温培养法观测了DOM和红壤水稻土C、N矿化的关系。结果表明,去除DOM显著降低了培养期间土壤有机质的累计矿化量。其中土壤有机碳的累计矿化量下降了11.4%～20.8%(平均15.4%),且其影响主要体现在培养前期;土壤有机氮的累计矿化量下降了16.4～22.9%(平均19.2%)。研究结果初步表明,虽然DOM只占土壤有机质的很少一部分,但在红壤水稻土C、N矿化中起重要作用。Dissolved organic matter （DOM） is considered important in the transport and supply of carbon （C） and nitrogen （N） to microorganisms and has a major role in decomposition of soil organic matter. However the contribution of DOM to microbially mediated C and N transformations in paddy soils is not quantified. Laboratory incubation was conducted to investigate the relationship between DOM and carbon and nitrogen mineralization of paddy soils in subtropical China. The results showed that the cumulative mineralization of soil organic carbon decreased significantly 11.4% - 20.8% with an average of 15.4% and soil organic nitrogen decreased 16.4% - 22.9% with an average of 19.2% after DOM removed. The effects of DOM removal on mineralization of soil organic carbon were distinct in the prophase of incubation. This data illustrate that whilst DOM is a small component of the soil OM, it plays a significant role in mineralization of carbon and nitrogen within these agricultural soils.

关 键 词：红壤水稻土 溶解性有机质 碳氮转化 

分 类 号：S153.6[农业科学—土壤学]