增温施肥对农田土壤有机碳和全氮含量及δ^(13)C、δ^(15)N值的影响  

Effects of warming and fertilization on soil organic carbon and total nitrogen contents,andδ^(13)C andδ^(15)N in farmland

作　　者：李佳珍 董文旭[3] 陈拓 胡春胜[3] LI Jiazhen;DONG Wenxu;CHEN Tuo;HU Chunsheng(Peking University Shenzhen Graduate School,Shenzhen 518055,China;Center for Shenzhen Marine Development Research and Promotion,Shenzhen 518034,China;Center for Agricultural Resources Research,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences/Hebei Key Laboratory of Soil Ecology/Key Laboratory of Agricultural Water Resources,Chinese Academy of Sciences,Shijiazhuang 050022,China;China Center for Special Economic Zone Research,Shenzhen University,Shenzhen 518060,China;Center for Shenzhen Natural Resources and Real Estate Evaluation and Development Research,Shenzhen 518034,China)

机构地区：[1]北京大学深圳研究生院,深圳518055 [2]深圳市海洋发展研究促进中心,深圳518034 [3]中国科学院遗传与发育生物学研究所农业资源研究中心/河北省土壤生态学重点实验室/中国科学院农业水资源重点实验室,石家庄050022 [4]深圳大学中国经济特区研究中心,深圳518060 [5]深圳市自然资源和不动产评估发展研究中心,深圳518034

出　　处：《中国生态农业学报（中英文）》2022年第5期842-850,共9页Chinese Journal of Eco-Agriculture

基　　金：国家重点研发计划项目(2021YFD190100202)资助。

摘　　要：农田土壤是重要的碳氮库,对气候变化极其敏感,但土壤碳氮循环对气候变化的响应目前还不清楚。在全球变暖背景下,为了实现我国碳达峰、碳中和目标,研究增温对土壤有机碳、全氮含量及其碳氮同位素的影响具有重要的现实意义。本研究采用红外辐射加热器模拟全球变暖,使5 cm土壤温度增加约2℃。通过测定灌溉前后土壤有机碳和全氮含量及δ^(13)C和δ^(15)N值的变化,研究增温、施氮和灌溉对华北平原小麦田土壤碳氮库的影响。试验共设4个处理:不施氮不增温(N0T0)、不施氮增温(N0T1)、施氮不增温(N1T0)和施氮增温(N1T1)。结果表明:灌溉前,增温降低了土壤有机碳含量,0~10 cm土层N1T1处理与不增温处理(N0T0和N1T0)之间差异显著(P<0.05),10~20 cm土层N1T1处理与其他处理差异均显著(P<0.05);灌溉后,增温虽有降低土壤有机碳含量的趋势,但差异不显著;施氮条件下,增温显著提升了δ^(13)C值(P<0.05)。增温降低了土壤全氮含量,并在灌溉前10~20 cm土层和灌溉后0~10 cm土层达显著水平(P<0.05);增温提升了土壤δ^(15)N值,灌溉前0~10 cm土层N0T0处理与增温处理(N0T1和N1T1)差异显著(P<0.05),灌溉后0~10 cm土层仅N0T1和N1T0处理间差异显著(P<0.05),而10~20 cm土层增温处理(N0T1和N1T1)均与N1T0处理差异显著(P<0.05)。同一处理同一时期,土壤有机碳和全氮的含量随土壤深度的增加而降低,δ^(13)C和δ^(15)N值随深度增加而升高,但土壤有机碳和δ^(13)C值的变化差异不显著,全氮含量和δ^(15)N值的变化差异显著(P<0.05)。土壤有机碳、全氮含量及δ^(13)C和δ^(15)N值在灌溉前后的差异均不显著。连续5年的增温施氮试验表明,未来气候变暖可能会加快土壤有机碳和全氮的分解,造成更多轻组有机碳损失。灌溉在短期内不会显著改变土壤碳氮含量及δ^(13)C和δ^(15)N值,但其长期影响还需进一步探究。此外,未来研究还应该重视多因Farmland soil is an essential terrestrial carbon and nitrogen pool that is highly sensitive to climate change.However,the response of soil carbon and nitrogen cycles to climate change remains unclear.Understanding the effect of warming on soil organic carbon is particularly important to achieving the goal of carbon peak and carbon neutralization in the context of global warming.Here,the infrared heaters were used to simulate warming and the soil temperature(5 cm depth)increased by approximately 2°C.The soil organic carbon,total nitrogen,δ^(13)C,andδ^(15)N contents were measured to assess the effects of warming,nitrogen addition,and irrigation on the soil carbon and nitrogen cycle.The experiment consisted of four treatments:no nitrogen addition and no warming(N0T0),no nitrogen addition and warming(N0T1),nitrogen addition and no warming(N1T0),and nitrogen addition and warming(N1T1).The results showed that warming decreased the soil organic carbon content before irrigation.There were significant differences between the N1T1 and no warming(N0T0 and N1T0)treatments at 0–10 cm depth(P<0.05),and between N1T1 and the other three treatments at 10−20 cm depth(P<0.05).Warming tended to decrease soil organic carbon content after irrigation.However,the difference was not statistically significant.Warming enhanced soilδ^(13)C in the nitrogen addition treatments(P<0.05)and decreased soil total nitrogen content,but the differences were only significant at the 10−20 cm depth before irrigation and at the 0–10 cm depth after irrigation(P<0.05).Soilδ^(15)N was enhanced in the warming treatment.However,the defferences were only significant between the N0T0 and warming(N0T1 and N1T1)treatments at 0−10 cm depth before irrigation(P<0.05),between N0T1 and N1T0 at 0−10 cm depth(P<0.05),and between N1T0 and the warming(N0T1 and N1T1)treatments at 10−20 cm after irrigation(P<0.05).The soil organic carbon and total nitrogen contents decreased with increasing soil depth,whileδ^(13)C andδ^(15)N increased with increasing so

关 键 词：增温 施氮 土壤有机碳 土壤全氮 δ^(13)C值 δ^(15)N值 

分 类 号：S3[农业科学—农艺学]