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作 者 ：邵立明^1,2,3;孔祥锐^1,2,3; 张后虎^1,2,3;何品晶^1,2,3

期 刊 ：应用生态学报 2008年 19卷 10期 页码：2265-2270

关键词：土壤；

摘 要 ：采用预设取样器和静态箱气相色谱法，对渗滤液灌溉条件下，土柱土壤不同深度剖面 N₂O的浓度以及N₂O和CO₂的表面释放通量进行了监测.结果表明: 渗滤液灌溉可促进N₂O的生成和释放，灌溉后24 h内土柱N₂O的释放通量与表土下10 cm（r=0.944,P< 0.01）、20 cm（r=0.799,P<0.01）、30 cm（r=0.666,P<0.01）和40 cm（r=0.482,P<0.05）处所生成的N₂O浓度呈显著相关，且相关程度依次递减.渗滤液灌溉还促进了CO₂的释放，但N₂O与CO₂释放通量之间无显著相关性（P>0.05）.渗滤液的灌溉负荷主要决定温室气体释放总量的强弱（N₂O和CO₂，以CO₂当量计），灌溉负荷为6 mm·d^-1条件下温室气体释放总量为灌溉负荷2 mm·d^-1的3倍多.采用表土下20 cm处灌溉方式可比表土下10 cm处灌溉方式削减47%的温室气体释放总量.渗滤液灌溉土壤14 d内，N₂O释放量约占温室气体释放总量的57.0%～91.0%.

Abstract:By using prefabricated probe and static chamber, the N₂O concentration at different depths along the soil columns irrigated by landfill leachate as well as the N₂O and CO₂ fluxes were determined. The results showed that leachate irrigation could promote the N₂O emission. Within the first 24 hours after irrigation, the N₂O fluxes from the soil columns were significantly correlated with the N₂O concentrations in the columns at the depths of 10 cm (r=0.944, P<0.01), 20 cm (r=0.799, P<0.01), 30 cm (r=0.666, P<0.01), and 40 cm (r=0.482, P<0.05), and the correlation decreased along the depths. Landfill leachate irrigation also promoted the CO₂ emission from the soil columns. There was no significant correlation between the emissions of N₂O and CO₂ (P>0.05). The irrigation loading of landfill leachate had a predominant effect on the total greenhouse gas emissions (including N₂O and CO₂ fluxes, based on CO₂-equivalent emissions). When the irrigation loading was 6 mm·d^-1, the total greenhouse gas emissions from the soil columns were 2 times higher than those when the irrigation loading was 2 mm·d^-1. 47% of the total greenhouse gas emissions were reduced from the soil columns when the leachate irrigation depth was at 20 cm, compared with the depth being at 10 cm. Within the 14 days under leachate irrigation, 57.0%-91.0% of the total greenhouse gas emissions were originated from N₂O emission.

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