不同种植年限旱田N2O排放研究  

Study on Nitrous Oxide Emission from Uplands of Different Reclamation Years

作　　者：江长胜[1] 王跃思[2] 宋长春 郝庆菊[1] 

机构地区：[1]西南大学资源环境学院,重庆400716 [2]中国科学院大气物理研究所,北京100029 [3]中国科学院东北地理与农业生态研究所,长春130012

出　　处：《水土保持学报》2008年第1期212-216,共5页Journal of Soil and Water Conservation

基　　金：中国科学院知识创新工程重大项目(KZCX1-SW-01);重庆市自然科学基金项目(CSTC,2006BB7350);西南大学博士启动基金项目

摘　　要：以三江平原沼泽湿地不同开垦年限(1987年、1993年开垦)的旱田(种植方式为大豆-冬闲)为研究对象,探讨了种植年限、降雨、土壤湿度以及植物参与对旱田N2O排放的影响。结果表明,种植年限越长,N2O排放量越高,1987年开垦的旱田N2O排放量显著高于1993年开垦的,这与土壤的理化性质有关;土壤有机碳和总氮含量随种植年限的增加而逐渐降低,而1δ5N随种植年限呈线性升高。在大豆生长季内,两种种植年限的旱田N2O通量具有相同的季节变化趋势,而降水条件是控制这一变化趋势的主要因素,N2O排放通量与观测日前6天的加权平均降水量呈线性正相关,与土壤体积含水量呈多项式正相关。另外,植物的参与降低了旱田土壤N2O的排放。Two uplands of different reclamation years （since 1987 and 1993, respectively） were selected in our study to research the effect of cultivation years, precipitation, soil moisture and plant on N2O emission. The resuits showed that the seasonal changes of N2O emission from the two uplands were same in the plant growing season. Precipitation was the main influencing factor for controlling the seasonal changes of N2O emission, which could be quantitatively described by a linear function of a weighted average precipitation of the last 6 days before measurement day. And N2O fluxes were correlated positively with soil moisture. The further analysis suggested that cultivation years be longer, N2O emission be higher. N2O emission from the upland of longer reclamation years （1987） was significantly higher that from the upland of later reclamation years （1993）, which caused by soil chemical characteristics. Soil organic carbon and total ,litrogen decreased with cultivation years, and δ^15N increased with cultivation years. The presence of plant reduced N2O emission from soils.

关 键 词：N2O排放 旱田 种植年限 降水 

分 类 号：S153[农业科学—土壤学] X511[农业科学—农业基础科学]