不同母质发育水稻土N_(2)O消耗潜力及环境影响因素  

Consumption potential of N_(2O) and its influencing factors in paddy soils with different parent materials

作　　者：杨曼 钟金梅 王薇[1] 赵丽娅[1,2] 李兆华 李昆[1,2] 王玲 YANG Man;ZHONG Jin-mei;WANG Wei;ZHAO Li-ya;LI Zhao-hua;LI Kun;WANG Ling(Hubei Key Laboratory of Regional Development and Environmental Response,Hubei University,Wuhan Hubei 430062;Hubei Rural Safe Drinking Water Engineering Technology Research Center,Wuhan Hubei 430062)

机构地区：[1]湖北省区域发展与环境响应重点实验室,湖北大学,湖北武汉430062 [2]湖北省农村安全饮用水工程技术研究中心,湖北武汉430062

出　　处：《中国土壤与肥料》2024年第4期35-44,共10页Soil and Fertilizer Sciences in China

基　　金：国家自然科学基金(41807043);湖北省区域发展与环境响应重点实验室基金项目[2020(A)003,2021(A)002]。

摘　　要：土壤是N_(2)O的源和汇,在淹水和厌氧条件下具有消耗N_(2)O的能力。稻田土壤长期处于淹水状态,为N_(2)O的消耗提供了有利的环境,从而减少了N_(2)O排放。目前,有关稻田土壤N_(2)O排放的相关研究已有很多,但关于稻田表层土壤N_(2)O的消耗能力及其与环境因素之间的关系研究较少。研究采集了第四纪红壤母质发育的壤土、湖积物砂土发育的砂质壤土、冲积土发育的粉砂质黏壤土3类土壤的各3个表层(0~5 cm)水稻土,风干后将其回填至具有5 cm深土柱的培养装置内,在土柱底部添加N_(2)O和添加氦气(He,对照)两个处理,于28℃下恒温淹水厌氧培养96 h。培养期间监测各土壤N_(2)O、N_(2)的动态变化,以及培养前后土壤养分的变化,量化N_(2)O消耗量和N2增量,以期揭示稻田表层土壤N_(2)O的消耗能力及其与环境因素之间的关系。结果表明,土壤剖面积累的N_(2)O有95.01%~99.92%被稻田表层土壤吸收,其中被还原为N2的N_(2)O量占总消耗量的64.50%~83.64%,表明淹水厌氧状态下,不同的水稻土均具有很强的N_(2)O吸收和消耗能力。研究还发现,3类土壤N_(2)O的消耗存在一定差异,其中影响砂质壤土N_(2)O消耗的主要环境因子为土壤砂粒含量,且两者之间存在显著的线性相关关系(R^(2)=0.964,P=0.000);土壤黏粒、粉砂粒、pH是粉砂质黏壤土N_(2)O消耗的主要环境影响因素,其中土壤黏粒与其消耗量呈显著线性相关(P<0.05);土壤速效钾和铵态氮增加量是影响壤土N_(2)O消耗的主要环境因子,其消耗量与速效钾之间在0.01水平上显著正相关。这些结果表明,土壤可溶性有机碳、土壤质地、土壤速效钾等是影响稻田土壤N_(2)O消耗的重要环境因子,且不同土壤N_(2)O消耗的环境影响因子存在差异,这将为调节土壤N_(2)O排放提供重要参考。Soil is a source and sink of N_(2)O and can consume N_(2)O under flooded and anaerobic conditions.Long-term flooding of paddy soil provides a favorable environment for N_(2)O consumption,thereby reducing N_(2)O emissions.N_(2)O emissions from paddy soils have been studied extensively,but research on the N_(2)O consumption capacity of paddy surface soil and its relationship with environmental factors is still lacking.In this paper,three types of paddy surface soils developed from quaternary red soil(loam,L),lake sediment sand(sandy loam,SL),and alluvial soil(silty clay loam,SCL)were selected to study their N_(2)O consumption capacity using a microcosm experiment(60% soil mass water content and anoxic conditions).Air-dried soils collected from 5 cm in depth were treated with N_(2)O addition(N_2O)or helium addition(control)and incubated for 96 h at 28℃.The dynamics of N_(2)O and N_2,as well as the changes in soil nutrients during cultivation were monitored.N_(2)O total consumption and N_(2) production were quantified to explore the consumption capacity of N_(2)O of the three types of paddy soils and their related factors.The paddy surface soils consumed 95.01%-99.92% of the N_(2)O in 5 cm soil depth,and the amount of N_(2)O reduced to N_(2) was 64.50%-83.64% of the total N_(2)O consumption.This indicated that different paddy soil had strong N_(2)O consumption capacity under flooded and anoxic states.There were significant differences in the N_(2)O consumption among the three soil types.The dominant factor affecting the N_(2)O consumption of SL soils was the soil sand content,with a significant linear correlation(R^(2)=0.964,P=0.000).Soil clay,silt,and pH were the main environmental factors affecting N_(2)O consumption in SCL soils,and soil clay was significantly linearly related to its consumption(P<0.05).Soil available potassium and the increment of ammonium nitrogen was the main factor affecting the consumption of N_(2)O in L soils.There was a significantly positive correlation between consumption and available

关 键 词：表层水稻土 N_(2)O消耗 土壤pH 土壤可溶性有机碳 土壤质地 淹水缺氧 

分 类 号：S154.1[农业科学—土壤学]