三江平原寒地稻田CH_4、N_2O排放特征及排放量估算   总被引：4，自引：1，他引：3  

王毅勇  陈卫卫  赵志春  顾江新 《农业工程学报》2008,24(10)

利用静态暗箱-气相色谱法,于2003-2006年对三江平原寒地稻田CH4、N2O通量进行了为期4年的田间原位观测研究.结果表明:三江平原寒地稻田CH4和N2O排放具有明显的季节变化,水稻生长季淹水期是CH4排放的强源,稻田排水后CH4排放显著下降,休闲期CH4排放微弱或呈弱吸收汇,整个生长季CH4排放呈现单峰型态,并随水稻植株生长和叶面积指数而变化;水稻生长季和休闲期N2O排放通量都很小,冬季休闲期有时还出现微弱的吸收现象.生长季一般在施肥和表土落干时都会出现不同强度的排放峰,除了几次比较显著的排放峰值外,其它淹水状态下N2O排放很弱;温度和土壤水分状况是影响稻田CH4和N2O排放的重要因子,稻田积水深度和气体排放无明显的相关性;水稻植株对稻田土壤CH4排放起促进作用而对稻田土壤N2O排放起抑制作用;稻田氮肥用量增加可以降低土壤CH4排放,但却增加了N2O的排放.根据试验数据对三江平原地区寒地稻田CH4和N2O排放总量估算值分别为0.1035 Tg/a和0.0021 Tg/a.  相似文献   

稻鸭共作对不同栽培环境稻季CH₄和N₂O排放的影响          下载免费PDF全文

王强盛  刘欣  许国春  余坤龙  张慧 《土壤》2023,55(6):1279-1288

稻田是大气温室气体甲烷(CH₄)和氧化亚氮(N₂O)的重要排放源, 稻田温室气体减排一直是生态农业研究的热点。目前, 采用水稻品种选择利用、水分控制管理、肥料运筹管理、耕作制度调整以及种养结合模式等方法来减少稻田温室气体排放有较好实践效应, 但不同稻田栽培环境(露地、网室)基础上的稻鸭共作对麦秸全量还田的稻田温室气体排放特征及相关土壤理化特性关联性的影响尚为少见。本研究采用裂区设计, 在两种栽培环境条件下, 以无鸭子放养的常规稻作和麦秸不还田为对照, 在等养分条件下分析麦秸全量还田与稻鸭共作模式对稻田土壤氧化还原电位、CH₄排放量、产CH₄潜力及CH₄氧化能力、N₂O排放量及N₂O排放高峰期土壤反硝化酶活性、全球增温潜势、水稻产量的影响, 为稻田可持续生产和温室气体减排提供参考。结果表明, 麦秆还田增加了稻田产CH₄潜力、提高了CH₄排放量, 降低了稻田土壤反硝化酶活性、土壤氧化还原电位和N₂O排放量, 整体上导致全球增温潜势上升96.89%~123.02%; 稻鸭共作模式, 由于鸭子的不间断活动提高了稻田土壤氧化还原电位, 降低了稻田产CH₄潜力, 增强了稻田CH₄氧化能力, 从而降低稻田CH₄排放量, N₂O排放量虽有提高, 整体上稻鸭共作模式的全球增温潜势较无鸭常规稻田下降8.72%~14.18%; 网室栽培模式显著提高了稻田土壤氧化还原电位, 降低稻田产CH₄潜力、CH₄氧化能力和土壤反硝化酶活性, 减少了稻田CH₄和N₂O排放量, 全球增温潜势降低6.35%~13.14%。本试验条件下, 稻田土壤的CH₄氧化能力是产CH₄潜力的2.21~3.81倍; 相同环境条件下, 稻鸭共作和麦秸还田均能增加水稻实际产量, 网室栽培的所有处理较相应的露地栽培减少了水稻实际产量1.19%~5.48%。本试验表明, 稻鸭共作和网室栽培可减缓全球增温潜势, 稻鸭共作和麦秸还田能够增加水稻实际产量。  相似文献   

耕作措施对华北农田CO₂排放影响及水热关系分析   总被引：7，自引：0，他引：7  

张宇  张海林  陈继康  伍芬琳  陈阜 《农业工程学报》2009,25(4):47-53

为探讨不同耕作措施对农田土壤呼吸排放的影响及其与土壤温度、水分之间的关系,该研究利用长期定位试验研究翻耕、旋耕、免耕3种耕作措施下冬小麦、夏玉米生育期农田CO₂的排放通量及其季节变化规律,并通过农田土壤温度、水分对CO₂的排放通量进行回归统计分析。结果表明：不同耕作措施下农田CO₂排放通量具有明显的季节排放规律,冬小麦、夏玉米生育期农田CO₂排放通量：翻耕＞旋耕＞免耕,且处理间差异都达到显著或极显著水平。不同耕作措施对农田土壤温度及土壤含水率具有显著的影响,免耕条件下农田各层土壤温度最低,冬小麦季免耕农田土壤水分含量高于其他两处理。各处理条件下农田CO₂排放通量与土壤温度具有显著的相关性,其中翻耕处理的CO₂排放通量与10 cm土温相关性最高,旋耕和免耕则均与20 cm土温相关性最高。当土壤温度高于10℃时CO₂排放通量与5 cm土壤含水率具有显著的相关性,此时土壤水分成为CO₂排放的主要影响因素。  相似文献   

不同施肥处理稻田甲烷和氧化亚氮排放特征   总被引：48，自引：14，他引：48  

秦晓波  李玉娥  刘克樱  万运帆 《农业工程学报》2006,22(7):143-148

采用静态箱－气相色谱法对长期不同施肥处理(NPKS、CK、NPK和NKM)的稻田CH₄和N₂O排放进行了观测。结果表明，稻田CH₄和N₂O排放季节变化规律明显不同，二者排放通量季节变化呈显著负相关(p<0.01)。与单施化肥和CK相比，施用有机肥显著促进CH₄排放，排放量最高的NPKS处理早晚稻田排放量分别是：526.68 kg/hm²和1072.92 kg/hm²。对于N₂O排放，早稻田各处理间差异不显著，NPK处理排放量最大，为1.48 kg/hm²；晚稻田各处理差异极显著(p<0.01)，NPKS处理排放量最大，为1.40 kg/hm²。晚稻田CH₄排放通量和10 cm土层温度及土壤pH值相关极显著(p<0.01)，并与二者存在显著的指数关系。没发现N₂O排放通量与温度及pH值间存在显著相关。稻田CH₄和N₂O排放受多种因素影响，但对全球变暖的贡献率CH₄远大于N₂O。NPKS处理的增温潜势最大，NPK处理的最小。  相似文献   

等高绿篱--坡地农业复合系统土壤N₂O排放特征     

程艳辉  赵书华  莫琼  郭忠录  蔡崇法 《中国生态农业学报》2013,21(6):700-706

N2O是一种重要的温室气体, 具有很强的温室效应。当前全球变化条件下, 人类活动和农业生产行为产生的N₂O排放增加是当前倍受关注的问题。本研究于2008年11月-2009年10月, 利用静态箱 气相色谱技术对亚热带地区紫穗槐(Amorpha fruticosa L.)绿篱枝叶还田条件下冬小麦 夏玉米轮作田土壤N₂O排放通量进行原位监测, 观测紫穗槐枝叶移出(AR)、翻施(AI)、表施(AC)及作物单作(CK)4种处理下整个生长季土壤N₂O的排放量, 对等高绿篱 坡地农业复合生态系统土壤N₂O排放通量变化及其影响机制进行研究。结果表明, 整个冬小麦 夏玉米轮作期, 4个处理土壤N₂O排放通量呈现出相似的季节变化特征, AR、AI、AC、CK处理全生长季的排放总量为127.62 mg·m^-2、209.66 mg·m^-2、208.73 mg·m^-2、77.52 mg·m^-2。作物不同生育阶段N₂O日均排放通量在冬小麦季表现为: 开花-成熟期>拔节-开花期>出苗-拔节期; 在夏玉米季表现为: 拔节-抽雄期>播种-拔节期>抽雄-成熟期。本试验综合评估了等高绿篱 坡地农业复合生态系统土壤N2O排放通量变化及其影响机制。研究显示, 土壤N₂O排放通量在冬小麦季与土壤温度相关性显著, 在夏玉米季与土壤水分相关性显著。在复合生态系统中紫穗槐复合种植及枝叶还田显著促进土壤N2O排放, 翻施处理产生的N2O量大于表施处理。  相似文献   

地膜覆盖对土壤中N₂O释放的影响   总被引：2，自引：0，他引：2  

朱咏莉  吴金水  韩建刚 《农业工程学报》2004,20(3):222-225

研究地膜覆盖下土壤中N₂O释放可为进一步探明膜下土壤中N₂O的传输、消耗和排放到大气的动力学过程提供理论依据。在2001年3月至6月和2001年10月至2002年6月连续两个冬小麦生长季，采用静态漏斗法和揭膜—封闭箱法测定了地膜覆盖下耕层5、10、20 cm土层处和地表处N₂O的释放特征及相应土壤性质。结果表明：地膜覆盖下，地表和耕层10、20 cm土层处N₂O释放通量显著增加；0～5 cm土层土壤水分和10～20 cm土层土壤硝态氮的浓度的变化分别解释了休闲地和冬小麦地土壤中N₂O释放通量85.23%和92.11%的变异，它们是膜下休闲地和冬小麦地土壤中N₂O释放通量增加的主要原因。该结论对地膜覆盖下科学地控制农田水分、养分以及地膜覆盖在中国西北地区的科学使用和推行具有实际意义。  相似文献   

稻草生物炭对干湿交替稻田CH₄和N₂O排放的影响     

刘畅  迟道才  张丰  韩宏伟  衣本骥  王喆  孟军  陈涛涛 《农业工程学报》2023,39(14):232-242

为探究稻草生物炭和灌溉方式对稻田CH₄和N₂O排放的影响,揭示生物炭在干湿交替稻田中的应用潜力,该研究采用大田裂区试验,设置常规淹灌（I_CF）和干湿交替灌溉（I_AWD）2种灌溉方式,不施生物炭（B₀）和施20 t/hm²生物炭（B₂₀）2种施炭水平,连续3 a对稻田CH₄、N₂O排放和水稻产量进行了观测研究。结果表明：与I_CF相比,I_AWD在显著降低CH₄排放（63.03%～78.89%）的同时也促进了N₂O排放（100%～122.67%）。生物炭施加首年对CH₄排放无显著影响,但第2年和第3年分别显著减少CH₄排放21.99%和38.21%;而对N₂O排放3 a均起到抑制作用,降幅达28.26%～33.10%。生物炭3 a平均增加土壤有机碳27.03%。施生物炭第1年水稻略有减产,但第2和第3年表现为正效应。主要是由于初期秸秆生物炭碱性较大,表现出了明显的石灰效应;但随着pH值逐步恢复正常后,生物炭固碳减排和缓释增效特性逐渐显现。尤其在2021年,B₂₀较B₀增产11.02%,显著降低37.50%的全球增温潜势（global warming potential,GWP）和42.86%的温室气体排放强度（greenhouse gas intensity,GHGI）;同时,在B₀条件下,I_AWD较I_CF增加137.21%的N₂O排放,但B₂₀条件下降低I_AWD处理32.52%的N₂O排放,有效抑制I_AWD对N₂O排放增加的负面效应。整体来看,与I_CFB₀处理相比,I_AWDB₂₀处理显著降低CH₄排放,降幅为83.78%,同时降低77.98%的GWP和78.95%的GHGI。该研究为揭示生物炭固碳减排的正效应及其在稻田生态系统中的应用潜力,同时全面探究其对稻田增产、CH₄和N₂O排放的年限影响,为缓解实际稻田生产过程中CH₄和N₂O的排放,实现稻田绿色、高效、可持续生产提供理论依据。  相似文献   

耕作措施对温带半干旱地区土壤温室气体(CO₂、CH₄、N₂O)通量的影响   总被引：4，自引：1，他引：3  

汪婧  蔡立群  张仁陟  王友玲  董稳军 《中国生态农业学报》2011,19(6):1295-1300

通过设置在甘肃省定西市李家堡镇的不同耕作措施试验, 利用CO₂分析仪、静态箱-气相色谱法对双序列轮作次序下春小麦地、豌豆地生育期内CO₂、CH₄和N₂O通量进行了测定。试验结果表明: 4种耕作措施下春小麦地和豌豆地在生育期内均表现为CO₂源、N₂O源和CH₄汇的功能。传统耕作不覆盖、免耕不覆盖、免耕秸秆覆盖和传统耕作结合秸秆还田下, 春小麦生育期内平均土壤CO₂通量(μmol·m^-2·s^-1)分别为0.203 6、0.221 2、0.241 8、0.224 9, CH₄通量(mg·m^-2·h^-1)分别为-0.041 6、-0.078 0、-0.081 8、-0.053 7, N₂O通量(mg·m^-2·h^-1)分别为0.089 1、0.069 2、0.046 1、0.065 6; 豌豆生育期内平均土壤CO₂通量(μmol·m^-2·s^-1)分别为0.273 6、0.261 6、0.218 1、0.236 0, CH₄通量(mg·m^-2·h^-1)分别为-0.055 0、-0.073 7、-0.066 2、-0.054 5, N₂O通量(mg·m^-2·h^-1)分别为0.123 4、0.084 7、0.080 6、0.035 0。少免耕及小麦秸秆覆盖有利于减少土壤CO₂排放通量, 免耕不覆盖、免耕秸秆覆盖及传统耕作结合秸秆还田均能不同程度地增加CH₄吸收通量、减少N₂O排放通量。综合来看, 免耕不覆盖、免耕秸秆覆盖和传统耕作结合秸秆还田3种保护性耕作措施有助于减少土壤温室气体的排放量。春小麦地CO₂通量随着土壤温度、土壤含水量的逐渐升高而增大; CH₄吸收通量随着土壤含水量的逐渐升高而增大, 而随着土壤温度的逐渐升高而减小。豌豆地CO₂通量的变化与土壤含水量存在极显著正相关关系; 而春小麦地N₂O通量则与平均土壤温度呈显著正相关, 豌豆地则为极显著正相关。  相似文献   

根际CO₂浓度对网纹甜瓜根系生长和活力的影响   总被引：1，自引：1，他引：0  

李天来  陈亚东  刘义玲  覃兴 《农业工程学报》2009,25(4):210-215

采用气雾法栽培方式,在开花结果期对网纹甜瓜进行不同浓度的根际CO₂处理,探讨根际CO₂浓度对网纹甜瓜根系生长及伤流中4种内源激素含量的影响。结果表明：随着处理时间的延长,根际CO₂浓度为2500 μL/L处理和5000 μL/L处理与350 μL/L处理相比,根系的生长受到了抑制,根系活力呈先升高后降低的趋势。同时伤流液体积、电导率、pH值以及促进生长类激素IAA（生长素）、ZT（玉米素）、GA3（赤霉素）含量显著降低,而ABA（脱落酸）含量升高。说明根际CO₂浓度超过2500 μL/L就会明显影响网纹甜瓜根系生长和根系合成生长类内源激素的能力,这可能也是土壤栽培和基质无土栽培较汽雾法栽培减产的重要原因之一。  相似文献   

冬季淹水稻田CH₄排放通量及其δ¹³C的时间变化特征   总被引：1，自引：0，他引：1  

张晓艳  张广斌  纪洋  马静  徐华  蔡祖聪 《土壤学报》2012,49(2):296-302

通过田间试验研究了持续淹水稻田冬季休闲期和水稻生长期CH4排放通量及其稳定性碳同位组成的时间变化。结果表明:CH4排放在冬季休闲期从4月份呈逐渐上升趋势,至6月份出现排放峰,为CH46.4 mg m-2h-1;水稻移栽后则迅速增加,于7月和8月出现两个排放峰,分别为CH423.1 mg m-2h-1和CH429.8 mg m-2h-1,此后急剧下降,末期稻田排水落干期间出现一个排放峰。冬季休闲期CH4排放总量为CH43.3 g m-2,占全年排放总量的8.9%。稻田排放的δ13CH4在冬季休闲期后期逐渐从-51‰上升至-44‰,然后下降至-56‰。水稻移栽后,δ13C值从-62‰迅速降至-68‰,然后慢慢上升至-60‰,并在较长一段时间内保持不变,后期再次富集13C。末期排水落干对排放δ13CH4影响显著。排放δ13CH4在水稻生长期较冬季休闲期低得多,原因在于冬季休闲期的CH4氧化率很高(60%～90%),而水稻生长期的CH4氧化率相对较低(10%～80%)。全观测期内,CH4排放通量的季节变化均与土壤温度显著正相关(p<0.01),与土壤Eh显著负相关(p<0.01),与δ13CH4呈显著负相关(p<0.05)。  相似文献   

Nitrous oxide and methane emissions from different soil suspensions: effect of soil redox status   总被引：6，自引：0，他引：6  

K. Yu  Z. Wang  A. Vermoesen  W. Patrick Jr  O. Van Cleemput 《Biology and Fertility of Soils》2001,34(1):25-30

Four soil samples from fields of different land use [US (paddy field), China (paddy field) and Belgium (maize and wheat fields)] were incubated as soil suspension (soil:water ratio 1:4) to study the N₂O and CH₄ emission under different soil redox potential conditions. The results show that the N₂O emission was regulated within a narrow redox potential range of +120 to +250 mV, due to the balance of N₂O production and its further reduction to N₂. Methane emission occurred below a soil specific redox potential point, and the emission rates were inversely related to soil redox potentials. Both linear and exponential relationships between CH₄ emission and the soil redox potential were significant. By extrapolating the linear relationship of CH₄ emission against soil redox potential, the critical redox potentials for CH₄ production were estimated at about -170 (US paddy soil), -150 (Chinese paddy soil), -215 (Belgian maize soil), and -195 mV (Belgian wheat soil), respectively. In addition, the results indicate that a soil with a lower critical redox potential for CH₄ production had a higher CH₄ production potential. In this study, N₂O and CH₄ emissions were found to occur at a distinctly different soil redox potential condition. The range of soil redox potential values where both N₂O and CH₄ emissions were low was different for different soils, but it was situated between +120 and -170 mV. This is a wide redox potential range enabling field management practices to minimize both N₂O and CH₄ emissions from wetland ecosystems.  相似文献   

Wheat straw management affects CH₄ and N₂O emissions from rice fields   总被引：1，自引：0，他引：1  

Jing Ma  Erdeng Ma  Hua Xu  Kazuyuki Yagi 《Soil biology & biochemistry》2009,41(5):1022-1028

A 3-year field experiment was conducted in Jiangsu Province, China from 2004 to 2006 to investigate CH₄ and N₂O emissions from paddy fields as affected by various wheat straw management practices prior to rice cultivation. Five methods of returning wheat straw, no straw, evenly incorporating, burying straw, ditch mulching and strip mulching, were adopted in the experiment. Evenly incorporating is the most common management practice in the region. Results showed that compared with no straw, evenly incorporating increased CH₄ emission significantly by a factor of 3.9-10.5, while decreasing N₂O emission by 1-78%. Methane emission from burying straw was comparable with that from evenly incorporating, while N₂O emission from burying straw was 94-314% of that from evenly incorporating. Compared with evenly incorporating, CH₄ emission was decreased by 23-32% in ditch mulching and by 32% in strip mulching, while N₂O emission was increased by a factor of 1.4-3.7 in ditch mulching and by a factor of 5.1 in strip mulching. During the rice-growing season, the emitted N₂O was negligible compared to that of emitted CH₄. No significant difference in grain yield was observed between ditch mulching, burying straw, evenly incorporating and no straw. Compared with no straw, the grain yield was increased by 27% in strip mulching. Based on these results, the best management practice for returning wheat straw to the soil is strip mulching wheat straw partially or completely onto the field surface, as the method reduced CH₄ emission from rice fields with no decrease in rice yield.  相似文献   

Nitrous oxide and methane emissions during rice growth and through rice plants: effect of dicyandiamide and hydroquinone   总被引：4，自引：0，他引：4  

X. Xu  P. Boeckx  Y. Wang  Y. Huang  X. Zheng  F. Hu  O. Van Cleemput 《Biology and Fertility of Soils》2002,36(1):53-58

There is growing interest in N₂O and CH₄ transport through rice plants, but very little information is available on the effects of inhibitors on these gaseous emissions during rice growth and through rice plants. The closed chamber technique was used to study the effect of the urease inhibitor hydroquinone (HQ) and the nitrification inhibitor dicyandiamide (DCD) on N₂O and CH₄ emissions. As rice plants grew, the N₂O emission through rice plants was significantly reduced in all treatments; N₂O emissions were always lower in the presence than in the absence of inhibitor(s). These variations paralleled those in NO₃^--N content of fresh rice plants. During the rice growth period, increasing NO₃^--N content in rice plants paralleled the increase in the N₂O emission through rice plants. Hence, NO₃^--N in young rice plants can substantially contribute to the plant-mediated N₂O flux. A substantial CH₄ emission through rice plants occurred at their vigorous growth stage; CH₄ emissions were always lower in the presence than in the absence of inhibitor(s). Under the experimental conditions, application of DCD, especially of DCD+HQ, could significantly improve the growth of rice, and reduce the emissions of N₂O and CH₄ during rice growth.  相似文献   

优化施氮下稻-麦轮作体系土壤N₂O排放研究   总被引：6，自引：1，他引：5  

梁国庆  周卫﹡  夏文建  王秀斌  孙静文  李双来  胡诚  陈云峰 《植物营养与肥料学报》2010,16(2):304-311

采用了静态箱法研究优化施氮下湖北稻-麦轮作体系农田N2O排放特征。结果表明,农田N2O排放量随施氮量增加而增加。N2O排放通量峰值大约发生在施氮后的第3～7 d。小麦季土壤N2O排放量范围为N2O 2.43～4.84 kg/hm2,肥料氮通过N2O排放的损失率为0.54%～0.74%。水稻季土壤N2O排放量为N2O 0.89～2.45 kg/hm2,肥料氮通过N2O排放的损失率为0.39%～0.47%。小麦季和水稻季施氮后0～15 d N2O排放量占当季总排放量的百分比分别为62.79%～66.72%和87.97%～93.14%。与习惯施氮相比,基于作物阶段氮素吸收增加追肥比例和施氮次数的优化施氮能有效减少土壤N2O排放。  相似文献   

秸秆条带状覆盖对稻田CH_4和N_2O排放的影响   总被引：2，自引：1，他引：1  

马静  徐华  蔡祖聪  八木一行 《土壤学报》2010,47(1):84-89

采用3种秸秆还田方式(对照、秸秆均匀混施和秸秆条带状覆盖)进行田间试验,观测稻田CH4和N2O的排放通量,以探讨秸秆条带状覆盖对稻田CH4和N2O排放的影响。结果表明:秸秆条带状覆盖的CH4排放量是对照的2.7倍,二者的N2O排放量无明显差异;秸秆条带状覆盖的稻田CH4排放量较秸秆均匀混施减少32%,其N2O排放量是后者的5.1倍;稻田排放CH4和N2O的全球增温潜势(GWP)为:秸秆均匀混施秸秆条带状覆盖对照,且差异显著;秸秆条带状覆盖的水稻产量分别较对照和秸秆均匀混施增加27%和17%。秸秆条带状覆盖是值得推荐的稻季秸秆还田方式。  相似文献   

Effect of the number of tillages in fallow season and fertilizer type on greenhouse gas emission from a rice (Oryza sativa L.) paddy field in Ehime,southwestern Japan     

Yo Toma  Shingo Oomori  Asuka Maruyama  Hideto Ueno  Osamu Nagata 《Soil Science and Plant Nutrition》2016,62(1):69-79

Agricultural fields, including rice (Oryza sativa L.) paddy fields, constitute one of the major sources of atmospheric methane (CH₄) and nitrous oxide (N₂O). Organic matter application, such as straw and organic fertilizer, enhances CH₄ emission from paddy fields. In addition, rice straw management after harvest regulates CH₄ emissions in the growing season. The interaction of tillage times and organic fertilizer application on CH₄ and N₂O emissions is largely unknown. Therefore, we studied the effects of fallow-season tillage times and fertilizer types on CH₄ and N₂O emissions in paddy fields in Ehime, southwestern Japan. From November 2011 to October 2013, four treatments, two (autumn and spring) or one (spring) in the first year, or two (autumn and spring) or three (autumn, winter, and spring) in the second year times of tillage with chemical or organic fertilizer application, were established. Gas fluxes were measured by the closed-chamber method. Increasing the number of tillage times from one to two decreased succeeding CH₄ emission and the emission factor for CH₄ (EF_CH4) in the rice-growing season, suggesting that the substrate for CH₄ production was reduced by autumn and spring tillage in the fallow season. Higher EF_CH4 [1.8–2.0 kg carbon (C) ha^?1 d^?1] was observed when more straw was applied (6.9–7.2 Mg ha^?1) in the second year. Organic fertilizer application induced higher CH₄ emission just after the application as basal and supplemental fertilizers, especially at a lower straw application rate. This indicated that EF_CH4 in the organically managed fields should be determined individually. Organic fertilizer application with two tillage times induced N₂O efflux during the rice-growing season in the second year, but N₂O emissions were not affected by winter tillage. Although paddy fields can act as an N₂O sink because of reduced soil conditions when straw application was high, application of organic C and nitrogen as fertilizer can enhance N₂O production by the denitrification process during the growing season, especially in the ripening stage when soil anaerobic conditions became moderate. These results suggest that negative emission factors for N₂O (EF_N2O) can be applied, and EF_N2O of organic fertilizer should be considered during the estimation of N₂O emission in the paddy field.  相似文献   

Water Management Influencing Methane and Nitrous Oxide Emissions from Rice Field in Relation to Soil Redox and Microbial Community     

《Communications in Soil Science and Plant Analysis》2012,43(13-14):1889-1903

Abstract

Methane (CH₄) and nitrous oxide (N₂O) emissions from an irrigated rice field under continuous flooding and intermittent irrigation water management practices in northern China were measured in situ by the static chamber technique during May to October in 2000. The intermittent irrigation reduced total growing‐season CH₄ emission by 24.22% but increased N₂O emission by 23.72%, when compared with the continuous flooding. Soil Eh and four related bacterial groups were also measured to clarify their effects on gaseous emissions. Three ranges of soil redox potential were related to gas emissions: below ?100 mV with vigorous CH₄ emission, above +100 mV with significant N₂O emission, and +100 to ?100 mV with little CH₄ and N₂O emissions. Intermittently draining the field increased soil oxidation, with a decrease in CH₄ emission and an increase in N₂O emission. In general the mid‐season drainage slightly increased the populations of methanotrophs, nitrifiers, and denitrifiers but decreased that of methanogens.  相似文献   

太湖地区不同水旱轮作方式下稻季甲烷和氧化亚氮排放研究   总被引：15，自引：0，他引：15  

张岳芳  周炜  陈留根  王子臣  朱普平  盛婧  郑建初 《中国生态农业学报》2013,21(3):290-296

为准确编制我国稻田温室气体排放清单及制定合理减排措施提供基础数据,选择太湖地区典型水稻种植区江苏省苏州市,研究设计了休闲水稻(对照,CK)、紫云英水稻(T1)、黑麦草水稻(T2)、小麦水稻(T3)和油菜水稻(T4)5种水旱轮作方式,采用静态箱气相色谱法,开展了不同水旱轮作方式下水稻生长季田间甲烷(CH4)和氧化亚氮(N2O)排放监测试验。试验结果表明:不同水旱轮作方式下水稻生长季CH4排放通量呈先升高后降低的变化趋势,CH4排放峰值出现在水稻生育前期,移栽至有效分蘖临界叶龄期CH4累积排放量占全生育期排放总量的比例为65%~81%,而N2O仅在水稻烤田期间有明显排放。水旱轮作方式对稻季CH4和N2O排放有极显著(P 0.01)影响,CH4季节总排放量表现为T1(283.2 kg.hm 2)CK(139.5 kg.hm 2)T3(123.4kg.hm 2)T4(114.7 kg.hm 2)T2(100.8 kg.hm 2),N2O季节总排放量顺序为T1 T4 T3 T2 CK,依次为1.06kg.hm 2、0.87 kg.hm 2、0.81 kg.hm 2、0.72 kg.hm 2和0.53 kg.hm 2。T1处理稻季排放CH4和N2O产生的增温潜势最高[7 396 kg(CO2).hm 2],显著(P 0.05)高于其他处理,比CK[3 646 kg(CO2).hm 2]增加103%,T2[2 735kg(CO2).hm 2]较CK减少25%(P 0.05)。紫云英水稻轮作方式增加了太湖地区水稻生长季的温室效应。  相似文献