摘要
在极端降水事件频发的背景下,为明确强降水对麦田不同肥期氨挥发损失的影响,本研究利用田间模拟降水试验,研究了强降水对麦田氨挥发损失和耕层土壤铵态氮含量及硝化潜势的影响,并结合微域试验分析了氨挥发损失与土壤含水量的关系。田间试验设置施氮处理(CF)与不施氮(CK)对照,以CF处理施肥时间为基准,分别在基肥、越冬肥和穗肥施肥后第7天模拟强降水(90 mm),监测农田氮素径流和渗漏损失,并进行连续10 d的氨挥发排放监测。结果表明,施肥显著提高中上层(0~10 cm)土壤的铵态氮含量,增加了降水驱动的生育前期(基肥期,越冬肥期)氮径流和渗漏损失,而穗肥期损失量相当。施肥和降水对基肥期氨挥发排放强度(AVI)无显著影响,但对追肥期(越冬肥期,穗肥期)的AVI影响显著。降水-施肥处理(CF-R)的追肥期AVI(越冬肥期35.02 mg·m^(-2)·d^(-1);穗肥期12.84 mg·m^(-2)·d^(-1))显著高于其他处理(越冬肥期15.46~17.29 mg·m^(-2)·d^(-1);穗肥期7.95~11.23 mg·m^(-2)·d^(-1))。此外,越冬肥期氨挥发损失对平均AVI的差异贡献高于穗肥期和基肥期。相关分析表明,表层(0~5 cm)土壤铵态氮含量与氨挥发损失强度呈显著线性关系(P<0.05)。但值得注意的是,非降水条件下CF和CK处理的追肥期AVI均无显著差异,且培养系统的NH_(3)挥发损失量随土壤持水量的增加而降低。而土壤硝化潜势分析表明,施肥对不同土层土壤的硝化潜势均无显著影响,但降水显著降低了中上层土壤的硝化潜势。研究表明,降水对施肥处理的氨挥发驱动效应是施肥后表层土壤氮素含量升高和降水后硝化潜势降低的叠加作用结果。除驱动麦田氮素径流和渗漏损失,强降水对追肥期氨挥发损失的激发效应应予重视,特别是在越冬肥期。
To clarify the effects of heavy precipitation on ammonia volatilization(AV)in wheat fields at different fertilization periods against the background of frequent extreme precipitation events,this study utilized field-simulated rainfall experiment to investigate the repercussions of heavy precipitation on AV,soil ammonium N content and nitrification potential of wheat fields.Concurrently,a micro-plot experiment was conducted to elucidate the correlation between AV and soil moisture.The field trials encompassed N application treatments(CF)alongside non-N application controls(CK).Employing the fertilization schedule of the CF treatment,a heavy rainfall event(90 mm)was simulated on the 7th day subsequent to the application of basal,wintering,and panicl fertilizer.Monitoring encompassed assessments of N runoff and leaching losses in the trialed plots,alongside continuous measurements of AV over a 10-day period.The results indicated that fertilization markedly elevated ammonium N levels within the upper-middle soil layers(0-10 cm)and exacerbated precipitation-drived N runoff and leaching losses during the earlier growth stages[basal(BFS)and overwintering(WFS)fertilization stages],with comparable losses observed during the panicle fertilization stage(PFS).The results also showed that both fertilization and precipitation had insignificant effects on AV at basal fertilizer stage,but significantly altered the ammonia volatilization intensity(AVI)during the two topdressing periods.The AVI of the precipitation-fertilization treatment(CF-R)during the topdressing periods(WFS,35.02 mg·m^(-2)·d^(-1);PFS,12.84 mg·m^(-2)·d^(-1))was markedly higher than those observed in the other treatments(WFS,15.46-17.29 mg·m^(-2)·d^(-1);PFS,7.95-11.23 mg·m^(-2)·d^(-1))where AVI ranged from 15.46 to 17.29 mg·m^(-2)·d^(-1) during WFS and 7.95 to 11.23 mg·m^(-2)·d^(-1) during PFS.Further analysis highlighted that AV were more pronounced during the WFS compared to BFS and PFS stages.Correlation analysis substantiated a significant linear
作者
赵素雅
刘强
杨梖
王宁
侯朋福
薛利红
杨林章
ZHAO Suya;LIU Qiang;YANG Bei;WANG Ning;HOU Pengfu;XUE Lihong;YANG Linzhang(Key Laboratory of Agro-Environment in Downstream of Yangtze Plain of Ministry of Agriculture and Rural Affairs,Institute of Agricultural Resources and Environment,Jiangsu Academy of Agricultural Sciences,Nanjing 210014,China;College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China;College of Forestry and Grassland,Nanjing Forestry University,Nanjing 210037,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2024年第9期2060-2068,共9页
Journal of Agro-Environment Science
基金
国家重点研发计划项目(2021YFD1700801)
江苏省重点研发计划项目(D21YFD17008)。
关键词
降水
施肥
氨挥发
土壤铵态氮
土壤含水量
precipitation
fertilization
ammonia volatilization
soil ammonium nitrogen
soil moisture
