中国农业科学 ›› 2022, Vol. 55 ›› Issue (4): 729-742.doi: 10.3864/j.issn.0578-1752.2022.04.009

• 土壤肥料·节水灌溉·农业生态环境 • 上一篇    下一篇

秸秆分解对两种类型土壤无机氮和氧化亚氮排放的影响

张学林(),吴梅,何堂庆,张晨曦,田明慧,李晓立,侯小畔,郝晓峰,杨青华,李潮海   

  1. 河南农业大学农学院/省部共建小麦玉米作物学国家重点实验室/2011河南粮食作物协同创新中心,郑州 450002
  • 收稿日期:2021-01-11 接受日期:2021-03-11 出版日期:2022-02-16 发布日期:2022-02-23
  • 作者简介:张学林,Tel:13643867669;E-mail: xuelinzhang1998@163.com, zxl1998@henau.edu.cn
  • 基金资助:
    国家重点研发计划课题(2018YFD0200605);河南省自然科学基金(182300410013);河南农业大学科技创新基金(30500712)

Effects of Crop Residue Decomposition on Soil Inorganic Nitrogen and Greenhouse Gas Emissions from Fluvo-Aquic Soil and Shajiang Black Soil

ZHANG XueLin(),WU Mei,HE TangQing,ZHANG ChenXi,TIAN MingHui,LI XiaoLi,HOU XiaoPan,HAO XiaoFeng,YANG QingHua,LI ChaoHai   

  1. Agronomy College, Henan Agricultural University/State Key Laboratory of Wheat and Maize Crop Science/Collaborative Innovation Center of Henan Grain Crops for 2011, Zhengzhou 450002
  • Received:2021-01-11 Accepted:2021-03-11 Online:2022-02-16 Published:2022-02-23

摘要:

【目的】明确作物秸秆分解对土壤无机氮和氧化亚氮(N2O)排放的影响,为不同土壤类型采用合理的氮肥用量,促进秸秆分解、增加土壤可利用养分、减少N2O等温室气体排放提供理论依据。【方法】室内采用尼龙网袋法,设置秸秆类型(小麦和玉米)、土壤类型(潮土和砂姜黑土)和氮肥用量(N0:0,N1:180 kg N·hm-2,N2:360 kg N·hm-2)三因素培养试验,并设置无秸秆无氮肥为对照(CK),测定了土壤无机氮含量、N2O和CO2排放通量以及土壤酶活性等参数。【结果】与CK相比,添加作物秸秆的N0处理土壤无机氮含量显著降低,每添加1 g小麦或玉米秸秆平均减少0.8 mg或0.4 mg土壤无机氮。与潮土相比,不同氮肥用量条件下砂姜黑土添加小麦秸秆后土壤无机氮含量降低16%,而添加玉米秸秆后增加41%。与添加小麦秸秆相比,潮土和砂姜黑土添加玉米秸秆后无机氮含量分别增加111%和252%。两种土壤添加小麦或玉米秸秆均促进N2O和CO2排放。与CK相比,添加小麦秸秆和玉米秸秆的N0处理土壤N2O排放累积量分别增加70%和47%;CO2排放累积量增加346%和154%;全球变暖潜力增加53%和71%。与潮土相比,砂姜黑土添加小麦秸秆和玉米秸秆后N2O排放通量降低38%和61%,N2O排放累积量降低12%和51%,CO2排放累积量降低28%和16%。与潮土相比,砂姜黑土添加小麦秸秆的全球变暖潜力增加13%,而添加玉米秸秆却降低44%。与添加小麦秸秆相比,潮土和砂姜黑土添加玉米秸秆后N2O排放累积量分别增加88%和6%;CO2排放累积量降低21%和6%。不同氮肥用量和土壤类型条件下添加玉米秸秆的全球变暖潜力比小麦秸秆高91%。与N0和N2处理相比,砂姜黑土添加小麦秸秆或玉米秸秆的同时配施适量氮肥(N1)降低N2O排放量以及全球变暖潜力。与CK相比,两种土壤类型添加小麦或玉米秸秆后土壤蔗糖酶活性增加,而过氧化氢酶和氧气含量降低。与添加小麦秸秆相比,两种土壤添加玉米秸秆后脲酶、蔗糖酶、过氧化氢酶活性降低。与潮土相比,砂姜黑土添加作物秸秆后脲酶、过氧化氢酶活性降低,氧气含量增加;而过氧化氢酶活性和氧气含量均与N2O排放通量呈显著负相关。【结论】小麦和玉米秸秆分解均降低土壤无机氮含量、促进温室气体排放。玉米秸秆分解过程中土壤无机氮含量和N2O排放量均高于小麦秸秆;潮土添加小麦或玉米秸秆的N2O排放量高于砂姜黑土;砂姜黑土添加小麦或玉米秸秆并配施适量氮肥不会增加土壤N2O排放和全球变暖潜力。生产上秸秆还田应综合考虑秸秆类型、土壤类型和氮肥用量。

关键词: 秸秆, 潮土, 砂姜黑土, 温室气体, 氮素矿化, 全球变暖潜力

Abstract:

【Objective】The purpose of this study was to examine the effects of crop residue decomposition on soil available nitrogen (N) and nitrous oxide (N2O) emissions, and provide a theoretical basis for reasonable N fertilizer rate in agricultural soils to promote residue decomposition, to increase soil available nutrients, and to reduce N2O emissions. 【Method】The indoor soil incubations with nylon decomposition bag were conducted to study the effects of crop residue types (wheat and maize), soil types (fluvo-aquic soil: AS and Shajiang black soil: LS) and N fertilizer rates (N0: 0; N1: 180 kg N·hm-2; N2: 360 kg N·hm-2) on soil N2O emission. A control (CK) without residue addition and N fertilizer input was also established for the two soil types. Inorganic N content, N2O and CO2 flux, and soil enzyme activity were measured in incubated soil. 【Result】Compared with CK, soil inorganic N content under N0 decreased significantly, which was decreased by 0.8 mg·g-1 for 1 g wheat residue addition or 0.4 mg·g-1 for 1 g maize residue addition. Compared with AS, soil inorganic N content in LS reduced by 16% with wheat residue addition, by 41% with maize residue addition. Compared with wheat residue addition, soil inorganic N content in AS and LS increased by 111% and 252% with maize residue addition, respectively. Compared with CK, both soil N2O and CO2 flux increased with wheat residue or maize residue addition, and the total accumulation of soil N2O flux under N0 treatment increased by 70% and 47% with wheat residue and maize residue addition, by 346% and 154% for CO2 accumulation, and by 53% and 71% for global warming potential, respectively. Compared with AS, soil N2O flux in LS reduced by 38% and 61% with wheat residue and maize residue addition, by 12% and 51% for the accumulation of N2O flux, and by 28% and 16% for the accumulation of CO2 flux, respectively. And the global warming potential in LS increased by 13% with the wheat residue addition in comparison with that in AS, while declined by 44% with maize residue addition. Compared with wheat residue addition, the accumulation of soil N2O flux with maize residue addition increased by 88% in AS, and by 6% in LS, and reduced by 21% and 6% for the accumulation of soil CO2 flux in AS and LS, respectively. And the global warming potential with maize residue addition was 91% higher than that of wheat residue addition under the conditions of different N fertilizer rates and soil types. Compared with N0 and N2, soil N2O flux and their global warming potential under N1 treatment reduced significantly with wheat residue or maize residue addition in LS. Compared with CK, soil invertase activity increased with wheat residue or maize residue addition in both AS and LS, while which declined for soil Catalase and O2 content. Compared with wheat residue addition, soil urease activity, Catalase, and invertase activities declined with maize residue addition. Compared with AS, soil urease and catalase activities in LS reduced with wheat residue or maize residue addition, while soil O2 content increased. The catalase activities and O2 content was significantly and negatively related with soil N2O flux. 【Conclusion】The decomposition of wheat residue and maize residue reduced soil inorganic N content while increasing soil N2O flux. Soil inorganic N content and N2O flux with maize residue addition were higher than that of wheat residue. Emissions of N2O from Fluvo-aquic soil with wheat or maize residue addition was higher than that from Shajiang black soil. When combined with suitable N fertilizer rate, neither residues additions in Shajiang black soil increased N2O flux and global warming potential. These results suggested that, in the field, comprehensive management methods by returning residue to soil should consider the residue type, soil type and rate of N fertilization.

Key words: crop residue, fluvo-aquic soil, Shajiang black soil, greenhouse gas, soil nitrogen mineralization, global warming potential