长期施肥下红壤玉米关键生育期氧化亚氮排放差异及其影响因素  

Red soil N_(2)O emission difference caused by fertilizers and other factors at the key growth stages of maize

作　　者：宋毅 张璐[2,3] 韩天富 申哲[2,3] 李继文 李冬初 孟红旗 Ntagisanimana Gilbert[2,3] 张会民 SONG Yi;ZHANG Lu;HAN Tian-fu;SHEN Zhe;LI Ji-wen;LI Dong-chu;MENG Hong-qi;Ntagisanimana Gilbert;ZHANG Hui-min(Institute of Resources and Environment,Henan Polytechnic University,Jiaozuo,Henan 454000,China;State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China/Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081,China;Red Soil Experimental Station of Chinese Academy of Agricultural Sciences in Hengyang/Qiyang Farmland Ecosystem National Observation and Research Station,Qiyang,Hunan 426182,China)

机构地区：[1]河南理工大学资源环境学院,河南焦作454000 [2]中国农业科学院农业资源与农业区划研究所/北方干旱半干旱耕地高效利用全国重点实验室,北京100081 [3]中国农业科学院衡阳红壤实验站/湖南祁阳农田生态系统国家野外科学观测研究站,湖南祁阳426182

出　　处：《植物营养与肥料学报》2023年第10期1794-1804,共11页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金(42207398);中国博士后科学基金资助项目(2022M723441);井冈山农高区省级科技专项(20222-051246)。

摘　　要：【目的】探究红壤区玉米关键生育期氧化亚氮(N_(2)O)的排放量及影响因素,为红壤区玉米季温室气体减排提供理论支撑。【方法】典型红壤长期施肥定位试验始于1990年,选取不施肥(CK)、氮钾化肥配施(NK)、氮磷钾化肥配施(NPK)3个处理,监测玉米苗期、喇叭口期、灌浆期和成熟期N_(2)O排放、温度和降雨量,测定了表层土壤理化性状和硝酸还原相关酶的活性。【结果】与CK相比,NK和NPK处理均显著提高了N_(2)O累积排放量,NPK处理显著增加苗期N_(2)O累积排放量,而NK处理显著提高了喇叭口期和灌浆期N_(2)O累积排放量,但两个处理的玉米生育期N_(2)O累积排放总量没有显著差异。从玉米苗期到成熟期,NK处理土壤pH整体呈下降趋势,降低了17.8%,而CK和NPK处理无显著变化;CK、NK和NPK处理土壤有机碳(SOC)整体呈上升趋势,分别较灌浆期升高了15.2%、16.4%和16.2%,NH_(4)^(+)-N含量呈逐渐降低趋势,而NO_(3)^(−)-N含量呈逐渐上升趋势。NPK处理苗期土壤NO_(3)^(−)-N含量显著高于NK处理,喇叭口期和灌浆期均低于NK处理,NH_(4)^(+)-N含量全生育期均显著低于NK处理。从苗期到成熟期,各处理反硝化酶(DE)活性呈下降趋势,CK、NK处理的降幅(59.1%、66.9%)高于NPK处理(29.1%);各处理硝酸还原酶(NR)活性均在喇叭口期最低,NK和NPK处理各生育期NR活性高于CK;亚硝酸还原酶各处理也在喇叭口期最低,CK和NK处理分别下降33.4%和76.2%,NPK处理较最大值降低23.5%。Pearson分析结果表明,各生育期N_(2)O累积排放量与生育期平均气温(TEM)、NO_(3)^(−)-N、SOC和NR呈显著正相关关系,与生育期累积降雨量(PCP)、pH和反硝化酶活性呈显著负相关关系。随机森林模型分析结果表明,苗期、喇叭口期、灌浆期、成熟期与N_(2)O累积排放量相关最显著的因素分别为pH、PCP、NR、SOC。【结论】在玉米不同生育期,影响土壤N_(2)O累积排放的主要因素不同,苗�【Objectives】We studied the nitrous oxide(N_(2)O)emission at the key growth stages of maize in red soils under different fertilizer applications,and the main factors relative to the emission,so as to provide theoretical base for reduction of N_(2)O emission in the red soil area.【Methods】The research based on a long-term fertilization experiment in the typical red soil region,started since 1990.Three of the treatments were selected for the research:no fertilization(CK),N and K fertilizer combined application(NK),and N,P and K fertilizer combined application(NPK).At seedling,big trumpet,grain filling and maturing stage of maize,the temperature,rainfall and N_(2)O emission were monitored,the top soil chemical indexes(pH,SOC,NH_(4)^(+)-N and NO_(3)^(−)-N content),and the activities of relative enzymes were analyzed.【Results】The N_(2)O emission was pulsed throughout maize season,and the NK and NPK treatment led to significantly higher soil cumulative N_(2)O emission than CK.NPK treatment significantly increased the N_(2)O emission at seedling stage,while CK treatment increased that at big trumpet and grain filling stage,the two treatments had similar total N_(2)O emission.From seedling to maturing stage,soil pH in NK treatment kept decreasing,with decrease range of 17.8%,while the pH in CK and NPK treatment did not changed significantly.Soil organic carbon kept an overall upward trend,with an increase range of 15.2%,16.4%and 16.2%in CK,NK,and NPK treatment,respectively.The NH_(4)^(+)-N in all treatment soils decreased while NO_(3)^(−)-N increased gradually.The NO_(3)^(−)-N in NPK treatment was higher than NK treatment at seedling stage but lower at big trumpet and grain filling stage,and the NH_(4)^(+)-N in NPK treatment was significantly lower than in NK treatment at all the stages.The activity of soil denitrification enzyme(DE)decreased by 59.1%,66.9%,and 29.1%from seedling to maturing stage in CK,NK and NPK treatment,respectively.The nitrate reductase(NR)activities in all the three treatment soils

关 键 词：长期施肥 红壤 玉米季 氧化亚氮排放 土壤pH 有机碳 反硝化酶活性 

分 类 号：S513[农业科学—作物学]