渗滤液灌溉土壤N2O释放及氨挥发的研究  

N_2O Emissions and Ammonia Volatilization from Leachate Irrigated Soils

作　　者：邵立明[1] 邱伟坚[1] 张后虎[1] 何品晶[1] 

机构地区：[1]同济大学环境科学与工程学院、污染控制与资源化研究国家重点实验室、长江水环境教育部重点实验室,上海200092

出　　处：《环境科学》2008年第12期3520-3524,共5页Environmental Science

基　　金：国家高技术研究发展计划(863)项目(2001AA644010,2003AA644020);国家自然科学基金重点项目(50538080);国家科技支撑计划项目(2006BAC06B05)

摘　　要：选用2种供试土壤(S1和S2),通过培养试验研究了渗滤液投加土壤后N2O释放、氨挥发及矿物氮的转化,并讨论了土壤理化性质对上述过程的影响.土壤pH值较大程度地决定了氨的挥发,仅投加渗滤液的碱性土S1在培养期的前5 d内测到氨挥发,通过氨挥发共损失了约3.0‰的渗滤液氮.投加同等含量的渗滤液后,不同土壤可导致N2O释放量近20倍的差异(p<0.01).土壤含水率(WFPS)影响了土壤中硝酸盐氮的生成速率,从而制约了N2O释放通量的高低.与WFPS为46%时相比,投加蒸馏水的土壤S1、投加渗滤液的土壤S1和土壤S2在WFPS为70%的条件下N2O的释放通量均值分别提高了6.5(p>0.05)、1.8(p>0.05)和2.2倍(p<0.05).渗滤液投加土壤在10 d培养期内,土壤S1和S2因N2O释放分别损失了41.1‰和2.3‰的渗滤液氮.为此,控制灌溉土壤的含水率(<70%WFPS),并选用酸性土壤可有效地控制渗滤液灌溉下N2O的释放和氨挥发.The effect of soil properties on N2O emissions and ammonia volatilization after leachate addition was investigated by soil S1 and S2 through incubation experiment. The conversions of soil NH4^＋ -N and NO3^- -N contents after leachate addition were evaluated as well. Soil pH dominantly determines the ammonia volatilization after leachate addition and ammonia volatilization only happens by soil S1 of alkaline nature within the first 5-day during the 10-day incubation. Approximately 3.0‰ leachate ammonia-N is lost via ammonia volatilization from soil S1. After being added the same amount of leachate ammonia-N, there is an approximately 20-fold gap of N2O emissions between two different soils：soil S1 and S2 （p 〈 0.01 ）. Soil moisture content affects the net generation rate of NO3^- -N contents substantially and N2O fluxes are thus regulated accordingly. Compared with soils moisture content at water-filled pore space （WFPS） of 46 %, N2 O fluxes are elevated by 6.5,1.8, and 2.2 times from the leachate added soil S1 without leachate irrigation （p 〉 0.05 ）, the leachate added soil S1 （p 〉 0.05 ）, and the leachate added soil S2 （p 〈 0.05）, respectively. During the 10-day incubation, N2O emissions cause 41.1‰ and 2.3‰ leachate NH4 -N loss from the leachate added soil S1 and S2, respectively. Therefore, avoiding excessively wet conditions （ 〈 70% WFPS） and selecting acidic soil could minimize the potential N2O emissions and ammonia volatilization under leachate irrigation.

关 键 词：N2O释放 氨挥发 渗滤液投加 土壤理化特性 含水率 

分 类 号：X705[环境科学与工程—环境工程]