厌气条件下百菌清对土壤N_2O和CH_4排放的影响  

The effects of chlorothalonil on nitrous oxide and methane emissions from soils under anaerobic conditions

作　　者：郎漫[1] 蔡祖聪[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,南京210008

出　　处：《环境科学学报》2009年第10期2110-2117,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No. 40621001)~~

摘　　要：在密闭、淹水、充N2的严格厌氧条件下对土壤进行了14d的培养试验,研究了杀菌剂百菌清在添加水平为田间施用量(FR)(5.5mg·kg-1),20倍(20FR)和40倍田间施用量(40FR)时对强酸性、酸性、中性和碱性土壤N2O和CH4排放的影响.结果表明,20FR和40FR的百菌清能够显著促进N2O向N2的还原,降低N2O排放,在酸性、中性和碱性土壤中培养14d后,对照处理的N2O排放量为0.076～0.46mg·kg-1,而20FR和40FR处理的N2O排放量为0.004～0.06mg·kg-1,降低了1个数量级.反硝化作用和有机氮矿化作用强的土壤中,百菌清减少N2O排放作用更明显.反硝化底物NO3-的存在对CH4的产生与排放具有显著的抑制作用.在加入百菌清未对NO3-浓度产生显著影响的土壤中,百菌清对CH4排放量没有明显影响,在对NO3-浓度产生显著影响的土壤中,CH4排放量随着NO3-的增加而减少,说明百菌清可能通过影响反硝化过程中NO3-的消耗而影响CH4排放.The effects of the fungicide chlorothalonil on nitrous oxide and methane emissions from strongly acidic,acidic,neutral and alkaline soils were investigated in laboratory anaerobic incubation tests. The tests were performed at 25℃ with addition rates of 5.5 mg·kg^-1 A. I. （field rate,FR）,20 （20FR） and 40 times （40FR） field rate. The results indicated that chlorothalonil at levels of 20FR and 40FR promoted the reduction of N2O to N2,thus decreasing N2O emission significantly with the strongest effect in acidic,neutral and alkaline soils. N2O production ranged from 0.0760.46 mg·kg^-1 in the control soils and 0.0040.06 mg·kg^-1 in 20FR and 40FR treatments at the end of incubation. The stronger the denitrification activities and organic nitrogen mineralization in soils,the more chlorothalonil mitigated N2O emission. For the soils in which denitrification was not significantly affected by chlorothalonil,no significant differences in CH4 emissions were observed at different chlorothalonil addition rates. However,CH4 emissions decreased at higher rates of chlorothalonil addition in the soils in which denitrification was significantly affected by chlorothalonil. Because the substrate NO3^- of denitrification inhibited CH4 production and emission significantly,the inhibition effect of chlorothalonil on CH4 emission probably resulted from its inhibition of NO3^- denitrification.

关 键 词：杀菌剂 氧化亚氮 甲烷 百菌清 

分 类 号：X53[环境科学与工程—环境工程]