秸秆还田与施氮对耕层土壤有机碳储量、组分和团聚体的影响

doi:10.3864/j.issn.0578-1752.2023.20.009

摘要/Abstract

摘要：

【目的】秸秆还田配施氮肥的固碳研究结果存在争议，为此展开本研究，旨在揭示秸秆还田配施氮肥对农田土壤固碳能力的影响以及固碳机理，为秸秆还田配施氮肥固碳研究提供依据。【方法】依托11年的长期定位试验，采用裂区设计，主处理为秸秆处理方式（还田与不还田），副处理为3个施氮水平，分别为不施氮（N0）、施氮 168 kg·hm^-2（N168）、336 kg·hm^-2（N336，过量施氮）。【结果】施用氮肥较不施氮肥小麦增产14.4%—19.5%，秸秆还田对产量影响不显著。秸秆还田显著提高土壤碳累积投入量70.8%（P<0.05），但对土壤有机碳储量影响不显著。与不施氮相比，施用氮肥分别显著提高土壤碳累积投入量和土壤有机碳储量7.7%—8.5%（P<0.05）和4.7%—8.1%（P<0.05）。施用氮肥显著提高土壤固碳速率32.7%—56.1%（P<0.05），过量施氮（N336）显著提高土壤固碳效率51.8%（P<0.05）;秸秆还田显著降低了土壤固碳效率30.9%（P<0.05）。施氮和秸秆还田均能提升土壤碳库容量，N0和N168处理已经达到碳饱和状态。秸秆还田后土壤可溶性有机碳（DOC）、微生物量碳（MBC）、易氧化有机碳（EO）含量分别提高4.6%、11.2%、4.5%。与不施氮（N0）相比，施氮（N168）和过量施氮（N336）的DOC分别提高14.1%、29.5%;MBC分别平均降低14.0%、28.0%;EO分别提高8.2%和11.5%。秸秆还田有利于土壤DOC/SOC、微生物熵的提高。施用氮肥有利于DOC/SOC的提升，但降低了微生物熵。秸秆还田与施用氮肥均对土壤EO/SOC没有影响。秸秆还田和施氮均有利于大团聚体（>0.25 mm）的提升，秸秆还田显著提升了大团聚体的有机碳含量5.2%。秸秆不还田下团聚体平均重量直径（MWD）和几何平均直径（GMD）随着氮水平增加表现出先提高后降低的趋势，还田下则表现为随氮水平的增加而增加，秸秆还田分别提升团聚体MWD和GMD 8.8%和7.5%，施用氮肥相较不施氮对MWD和GMD分别提升14.1%—22.7%和16.8%—23.4%。秸秆还田和施氮均能提高有机碳在大团聚体的分布。【结论】秸秆还田配施氮肥可以通过增加碳投入量，提高活性有机碳含量，降低微生物活性，提高团聚体对有机碳的保护来提高耕层碳储量。

关键词: 秸秆还田, 氮肥, 耕层, 碳储量, 活性碳组分, 团聚体

Abstract:

【Objective】The results of carbon sequestration studies on combining straw returning with nitrogen fertilizer are controversial. Aimed at such problem, this experiment was carried out to reveal the effects of combining straw returning with nitrogen fertilizer on Carbon sequestration capacity and mechanism of farmland, so as to provide a reference for the future research. 【Method】Based on 11 years of long-term positioning experiments, this paper adopted split-zone design, the main treatment included straw returning to soil and removal straw from field, and the subplots included three N application rate, which were no nitrogen (N0), 168 kg·hm^-2 (N168, nitrogen), and 336 kg·hm^-2 (N336, excessive nitrogen application). 【Result】Compared with wheat without nitrogen fertilizer, wheat yield increased by 14.4%-19.5% with nitrogen fertilizer. The effect of straw returning to the field on yield was not significant. Straw returning significantly increased the cumulative input of soil carbon by 70.8% (P<0.05), but had no significant effect on soil organic carbon storage. Compared N0, the nitrogen application significantly increased soil carbon accumulation input and soil organic carbon storage by 7.7%-8.5% (P<0.05) and 4.7%-8.1% (P<0.05), respectively. The application of nitrogen fertilizer significantly increased the carbon fixation rate by 32.7%-56.1% (P<0.05), and N336 significantly increased the soil carbon fixation efficiency by 51.8% (P<0.05); straw returning to the field did not significantly improve the soil carbon fixation rate, but significantly reduced the carbon fixation efficiency by 30.9% (P<0.05). Both nitrogen application and straw returning could improve soil carbon pool capacity, and N0 and N168 have reached carbon saturation. The content of soluble organic carbon (DOC), microbial biomass carbon (MBC) and easily oxidized organic carbon (EO) in the soil increased by 4.6%, 11.2% and 4.5% respectively after returning straw to the field. Compared N0, DOC under N168 and N336 increased by 14.12% and 29.54% respectively; MBC decreased by 14.0% and 28.0% on average, respectively; EO increased by 8.2% and 11.5%, respectively. Straw returning to the field was beneficial to the improvement of soil DOC/SOC and microbial entropy. Applying nitrogen fertilizer was beneficial to the increase of DOC/SOC, but reduced the microbial entropy. Both straw returning and nitrogen fertilizer application had no effect on soil EO/SOC. Both straw returning and nitrogen application were beneficial to the improvement of macroaggregates (>0.25 mm), and straw returning significantly increased the organic carbon content of macroaggregates by 5.2%. The average weight diameter (MWD) and geometric average diameter (GMD) of aggregates under non-return showed a trend of first increasing and then decreasing with the increase of nitrogen level, while under straw returning, it showed an increase with the increase of nitrogen level. Straw returning increased the MWD and GMD of aggregates by 8.8% and 7.5% respectively, and the application of nitrogen fertilizer increased the MWD and GMD by 14.1%-22.7% and 16.8%-23.4% respectively, compared with CK. Both straw returning and nitrogen application could improve the distribution of organic carbon in large aggregates. 【Conclusion】Straw returning with nitrogen fertilizer could increase carbon input, increase activated organic carbon content, reduce microbial activity, and improve the protection of organic carbon by aggregates.

Key words: straw returning, nitrogen fertilizer, tillage layer, carbon storage, activated carbon components, aggregates

郭戎博, 李国栋, 潘梦雨, 郑险峰, 王朝辉, 何刚. 秸秆还田与施氮对耕层土壤有机碳储量、组分和团聚体的影响[J]. 中国农业科学, 2023, 56(20): 4035-4048.

GUO RongBo, LI GuoDong, PAN MengYu, ZHENG XianFeng, WANG ZhaoHui, HE Gang. Effects of Long-Term Straw Return and Nitrogen Application Rate on Organic Carbon Storage, Components and Aggregates in Cultivated Layers[J]. Scientia Agricultura Sinica, 2023, 56(20): 4035-4048.

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参考文献 46

[1]	郭振, 王小利, 段建军, 焦克强, 孙沙沙, 段英华, 张雅蓉, 李渝, 蒋太明. 长期施肥对黄壤性水稻土有机碳矿化的影响. 土壤学报, 2018, 55(1): 225-235.
	GUO Z, WANG X L, DUAN J J, JIAO K Q, SUN S S, DUAN Y H, ZHANG Y R, LI Y, JIANG T M. Long-term fertilization and mineralization of soil organic carbon in paddy soil from yellow earth. Acta Pedologica Sinica, 2018, 55(1): 225-235. (in Chinese)
[2]	程琨, 潘根兴. “千分之四全球土壤增碳计划”对中国的挑战与应对策略. 气候变化研究进展, 2016, 12(5): 457-464.
	CHENG K, PAN G X. “Four per mille initiative: soils for food security and climate” challenges and strategies for China’s action. Climate Change Research, 2016, 12(5): 457-464. (in Chinese)
[3]	齐玉春, 郭树芳, 董云社, 彭琴, 贾军强, 曹丛丛, 孙良杰, 闫钟清, 贺云龙. 灌溉对农田温室效应贡献及土壤碳储量影响研究进展. 中国农业科学, 2014, 47(9): 1764-1773. doi: 10.3864/j.issn.0578- 1752.2014.09.011.
	QI Y C, GUO S F, DONG Y S, PENG Q, JIA J Q, CAO C C, SUN L J, YAN Z Q, HE Y L. Advances in research on the effects of irrigation on the greenhouse gases emission and soil carbon sequestration in agro-ecosystem. Scientia Agricultura Sinica, 2014, 47(9): 1764-1773. doi: 10.3864/j.issn.0578-1752.2014.09.011. (in Chinese)
[4]	Learning tool on Nationally Appropriate Mitigation Actions NAMAs in the Agriculture, Forestry and Other Land Use (AFOLU) sector. Rome: FAO, 2022
[5]	YIN H J. Balancing straw returning and chemical fertilizers in China: role of straw nutrient resources. Renewable and Sustainable Energy Reviews, 2018, 81: 2695-2702. doi: 10.1016/j.rser.2017.06.076
[6]	高洪军, 彭畅, 张秀芝, 李强, 朱平, 王立春. 秸秆还田量对黑土区土壤及团聚体有机碳变化特征和固碳效率的影响. 中国农业科学, 2020, 53(22): 4613-4622. doi:10.3864/j.issn.0578-1752.2020. 22.008.
	GAO H J, PENG C, ZHANG X Z, LI Q, ZHU P, WANG L C. Effects of corn straw returning amounts on carbon sequestration efficiency and organic carbon change of soil and aggregate in the black soil area. Scientia Agricultura Sinica, 2020, 53(22): 4613-4622. doi:10. 3864/j.issn.0578-1752.2020.22.008. (in Chinese)
[7]	LIU C, LU M, CUI J, LI B, FANG C M. Effects of straw carbon input on carbon dynamics in agricultural soils: a meta-analysis. Global Change Biology, 2014, 20(5): 1366-1381. doi: 10.1111/gcb.12517 pmid: 24395454
[8]	慕平, 张恩和, 王汉宁, 方永丰. 连续多年秸秆还田对玉米耕层土壤理化性状及微生物量的影响. 水土保持学报, 2011, 25(5): 81-85.
	MU P, ZHANG E H, WANG H N, FANG Y F. Effects of continuous returning straw to maize tilth soil on chemical character and microbial biomass. Journal of Soil and Water Conservation, 2011, 25(5): 81-85. (in Chinese)
[9]	KUZYAKOV Y. Priming effects: interactions between living and dead organic matter. Soil Biology and Biochemistry, 2010, 42(9): 1363-1371. doi: 10.1016/j.soilbio.2010.04.003
[10]	王桂红. 氮素影响秸秆降解与土壤有机碳矿化的微生物机制[D]. 贵阳: 贵州大学, 2018.
	WANG G H. The microbial mechanism of nitrogen affects straw degradation and soil organic carbon mineralization[D]. Guiyang: Guizhou University, 2018. (in Chinese)
[11]	霍启煜, 马丽娟, 徐悦轩, 闵伟, 侯振安. 秸秆还田方式及施氮量对滴灌棉田土壤有机碳氮的影响. 水土保持学报, 2022, 36(3): 207-212.
	HUO Q Y, MA L J, XU Y X, MIN W, HOU Z A. Effects of straw returning mode and nitrogen application rate on soil organic carbon and nitrogen in drip irrigated cotton field. Journal of Soil and Water Conservation, 2022, 36(3): 207-212. (in Chinese)
[12]	HU Q, LIU T, DING H. Application rates of nitrogen fertilizers change the pattern of soil organic carbon fractions in a rice-wheat rotation system in China. Agriculture, Ecosystems & Environment, 2022, 338: 108081. doi: 10.1016/j.agee.2022.108081
[13]	ZHENG B C, CHEN P, DU Q, YANG H, LUO K, WANG X C, YANG F, YONG T W, YANG W Y. Soil organic matter, aggregates, and microbial characteristics of intercropping soybean under straw incorporation and N input. Agriculture, 2022, 12(9): 1409. doi: 10.3390/agriculture12091409
[14]	戴相林, 刘雅辉, 孙建平, 赵子婧, 左永梅, 耿雷跃, 张俊娥. 秸秆还田和氮肥减施对滨海盐渍土稻田温室气体排放及氮肥利用率的影响. 应用与环境生物学报, 2023, 29(4): 994-1005.
	DAI X L, LIU Y H, SUN J P, ZHAO Z J, ZUO Y M, GENG L Y, ZHANG J E. Combined effects of straw return and reduced nitrogen fertilizer application on greenhouse gas emissions and nitrogen use efficiency in a coastal saline paddy field. Chinese Journal of Applied and Environmental Biology, 2023, 29(4): 994-1005. (in Chinese)
[15]	鲍士旦. 土壤农化分析. 3版. 北京: 中国农业出版社, 2000.
	BAO S D. Soil and Agricultural Chemistry Analysis. 3rd ed. Beijing: China Agriculture Press, 2000. (in Chinese)
[16]	李世清, 李生秀. 土壤微生物体氮测定方法的研究. 植物营养与肥料学报, 2000, 6(1): 75-83.
	LI S Q, LI S X. Study on the methods for measuring microbial biomass nitrogen in soils. Journal of Plant Natrition and Fertilizers, 2000, 6(1): 75-83. (in Chinese)
[17]	杨馨逸, 刘小虎, 韩晓日, 段鹏鹏, 朱玉翠, 齐文. 不同品种小麦下土壤微生物量和可溶性有机物对不同施氮量的响应. 中国农业科学, 2016, 49(7): 1315-1324. doi:10. 3864/j.issn.0578-1752.2016.07. 009.
	YANG X Y, LIU X H, HAN X R, DUAN P P, ZHU Y C, QI W.Responses of soil microbial biomass and soluble organic matter to different application rates of N: a comparison between Liaochun 10 and Liaochun 18. Scientia Agricultura Sinica, 2016, 49(7): 1315-1324. doi:10. 3864/j.issn.0578-1752.2016.07.009. (in Chinese)
[18]	WANG H, WANG S L, ZHANG Y J, WANG X L, WANG R, LI J. Tillage system change affects soil organic carbon storage and benefits land restoration on loess soil in North China. Land Degradation & Development, 2018, 29(9): 2880-2887. doi: 10.1002/ldr.v29.9
[19]	谢钧宇. 冬小麦/夏玉米体系长期施肥塿土固碳潜力及机制研究[D]. 杨凌: 西北农林科技大学, 2017.
	XIE J Y. Carbon sequestration and its mechanisms on an anthrosol under long-term fertilization regimes in winter wheat-summer maize cropping system[D]. Yangling: Northwest A & F University, 2017. (in Chinese)
[20]	朱树伟. 耕作方式与施氮量对土壤有机碳积累和小麦玉米产量的影响[D]. 泰安: 山东农业大学, 2022.
	ZHU S W. Effects of tillage methods and nitrogen application rates on soil organic carbon accumulation and yield of wheat and maize[D]. Taian: Shandong Agricultural University, 2022. (in Chinese)
[21]	YAN L M, XU X, XIA J. Different impacts of external ammonium and nitrate addition on plant growth in terrestrial ecosystems: a meta-analysis. Science of the Total Environment, 2019, 686: 1010-1018. doi: 10.1016/j.scitotenv.2019.05.448
[22]	NIU W J, HAN L, LIU X. Twenty-two compositional characterizations and theoretical energy potentials of extensively diversified China’s crop residues. Energy, 2016, 100: 238-250. doi: 10.1016/j.energy.2016.01.093
[23]	LU F. How can straw incorporation management impact on soil carbon storage? A meta-analysis. Mitigation and Adaptation Strategies for Global Change, 2015, 20(8): 1545-1568. doi: 10.1007/s11027-014-9564-5
[24]	LEMKE R L, VANDENBYGAART A J, CAMPBELL C A. Crop residue removal and fertilizer N: Effects on soil organic carbon in a long-term crop rotation experiment on a Udic Boroll. Agriculture, Ecosystems & Environment, 2010, 135(1/2): 42-51. doi: 10.1016/j.agee.2009.08.010
[25]	赵惠丽, 董金琎, 师江澜, 徐苗, 田霄鸿. 秸秆还田模式对小麦-玉米轮作体系土壤有机碳固存的影响. 土壤学报, 2021, 58(1): 213-224.
	ZHAO H L, DONG J J, SHI J L, XU M, TIAN X H. Effect of straw returning mode on soil organic carbon sequestration. Acta Pedologica Sinica, 2021, 58(1): 213-224. (in Chinese)
[26]	张叶叶, 莫非, 韩娟, 温晓霞, 廖允成. 秸秆还田下土壤有机质激发效应研究进展. 土壤学报, 2021, 58(6): 1381-1392.
	ZHANG Y Y, MO F, HAN J, WEN X X, LIAO Y C. Research progress on the native soil carbon priming after straw addition. Acta Pedologica Sinica, 2021, 58(6): 1381-1392. (in Chinese)
[27]	金琳, 李玉娥, 高清竹, 刘运通, 万运帆, 秦晓波, 石锋. 中国农田管理土壤碳汇估算. 中国农业科学, 2008, 41(3): 734-743. doi:10.3864/j.issn.0578-1752.2008.03.014.
	JIN L, LI Y E, GAO Q Z, LIU Y T, WAN Y F, QIN X B, SHI F. Estimate of carbon sequestration under cropland management in China. Scientia Agricultura Sinica, 2008, 41(3): 734-743. doi:10. 3864/j.issn.0578-1752.2008.03.014. (in Chinese)
[28]	李雨诺, 樊媛媛, 曹彬彬, 田霄鸿, 师江澜. 关中平原麦玉轮作体系作物秸秆不同还田模式下土壤有机碳和无机碳库变化特征. 应用生态学报, 2021, 32(8): 2703-2712. doi: 10.13287/j.1001-9332.202108.030
	LI Y N, FAN Y Y, CAO B B, TIAN X H, SHI J L. Soil organic and inorganic carbon pools as affected by straw return modes under a wheat-maize rotation system in the Guanzhong Plain, Northwest China. Chinese Journal of Applied Ecology, 2021, 32(8): 2703-2712. (in Chinese)
[29]	蔡岸冬. 我国典型农田土壤固碳效率特征及影响因素[D]. 北京: 中国农业科学院, 2016.
	CAI A D. Characteristics and influence factors of carbon sequestration efficiency from typical cropland in China[D]. Beijing: Chinese Academy of Agricultural Sciences, 2016. (in Chinese)
[30]	赵雅雯, 王金洲, 王士超, 武红亮, 黄绍敏, 卢昌艾. 潮土区小麦、玉米残体对土壤有机碳的贡献: 基于改进的RothC模型. 中国农业科学, 2016, 49(21): 4160-4168. doi:10.3864/j.issn.0578-1752.2016. 21.010.
	ZHAO Y W, WANG J Z, WANG S C, WU H L, HUANG S M, LU C A. Contributions of wheat and corn residues to soil organic carbon under fluvo-aquic soil area-based on the modified RothC model. Scientia Agricultura Sinica, 2016, 49(21): 4160-4168. doi:10.3864/ j.issn.0578-1752.2016.21.010. (in Chinese)
[31]	魏猛, 张爱君, 李洪民, 唐忠厚, 陈晓光, 王会, 诸葛玉平, 娄燕宏. 长期不同施肥对潮土有机碳储量的影响. 华北农学报, 2018, 33(1): 233-238. doi: 10.7668/hbnxb.2018.01.033
	WEI M, ZHANG A J, LI H M, TANG Z H, CHEN X G, WANG H, ZHUGE Y P, LOU Y H. Effect of different long-term fertilization on soil organic carbon storage in fluvo-aquic soil. Acta Agriculturae Boreali-Sinica, 2018, 33(1): 233-238. (in Chinese) doi: 10.7668/hbnxb.2018.01.033
[32]	徐阳春, 沈其荣, 冉炜. 长期免耕与施用有机肥对土壤微生物生物量碳、氮、磷的影响. 土壤学报, 2002, 39(1): 83-90.
	XU Y C, SHEN Q R, RAN W. Effects of zero-tillage and application of manure on soil microbial biomass c, n, and p after sixteen years of cropping. Acta Pedologica Sinica, 2002, 39(1): 83-90. (in Chinese)
[33]	LU X F, HOU E Q, GUO J Y, GILLIAM F S, LI J L, TANG S B, KUANG Y W. Nitrogen addition stimulates soil aggregation and enhances carbon storage in terrestrial ecosystems of China: a meta-analysis. Global Change Biology, 2021, 27(12): 2780-2792. doi: 10.1111/gcb.15604 pmid: 33742519
[34]	WEST T O, SIX J. Considering the influence of sequestration duration and carbon saturation on estimates of soil carbon capacity. Climatic Change, 2007, 80(1): 25-41. doi: 10.1007/s10584-006-9173-8
[35]	SIX J, CONANT R T, PAUL E A, PAUSTIAN K. Stabilization mechanisms of soil organic matter: implications for C-saturation of soils. Plant and Soil, 2002, 241(2): 155-176. doi: 10.1023/A:1016125726789
[36]	宋佳, 黄晶, 高菊生, 王亚男, 吴翠霞, 白玲玉, 曾希柏. 冬种绿肥和秸秆还田对双季稻区土壤团聚体和有机质官能团的影响. 应用生态学报, 2021, 32(2): 564-570. doi: 10.13287/j.1001-9332.202102.023
	SONG J, HUANG J, GAO J S, WANG Y N, WU C X, BAI L Y, ZENG X B. Effects of green manure planted in winter and straw returning on soil aggregates and organic matter functional groups in double cropping rice area. Chinese Journal of Applied Ecology, 2021, 32(2): 564-570. (in Chinese) doi: 10.13287/j.1001-9332.202102.023
[37]	王士超, 闫志浩, 王瑾瑜, 槐圣昌, 武红亮, 邢婷婷, 叶洪龄, 卢昌艾. 秸秆还田配施氮肥对稻田土壤活性碳氮动态变化的影响. 中国农业科学, 2020, 53(4): 782-794. doi:10.3864/j.issn.0578-1752. 2020.04.010.
	WANG S C, YAN Z H, WANG J Y, HUAI S C, WU H L, XING T T, YE H L, LU C A. Nitrogen fertilizer and its combination with straw affect soil labile carbon and nitrogen fractions in paddy fields. Scientia Agricultura Sinica, 2020, 53(4): 782-794. doi:10.3864/j.issn. 0578-1752.2020.04.010. (in Chinese)
[38]	杨艳华, 苏瑶, 何振超, 喻曼, 陈喜靖, 沈阿林. 还田秸秆碳在土壤中的转化分配及对土壤有机碳库影响的研究进展. 应用生态学报, 2019, 30(2): 668-676. doi: 10.13287/j.1001-9332.201902.026
	YANG Y H, SU Y, HE Z C, YU M, CHEN X J, SHEN A L. Transformation and distribution of straw-derived carbon in soil and the effects on soil organic carbon pool: a review. Chinese Journal of Applied Ecology, 2019, 30(2): 668-676. (in Chinese) doi: 10.13287/j.1001-9332.201902.026
[39]	王利利, 董民, 张璐, 杜相革. 不同碳氮比有机肥对有机农业土壤微生物生物量的影响. 中国生态农业学报, 2013, 21(9): 1073-1077.
	WANG L L, DONG M, ZHANG L, DU X G. Effects of organic manures with different carbon-to-nitrogen ratios on soil microbial biomass of organic agriculture. Chinese Journal of Eco-Agriculture, 2013, 21(9): 1073-1077. (in Chinese) doi: 10.3724/SP.J.1011.2013.01073
[40]	曾莉, 张鑫, 张水清, 王秀斌, 梁国庆, 周卫, 艾超, 张跃强. 不同施氮量下潮土中小麦秸秆腐解特性及其养分释放和结构变化特征. 植物营养与肥料学报, 2020, 26(9): 1565-1577.
	ZENG L, ZHANG X, ZHANG S Q, WANG X B, LIANG G Q, ZHOU W, AI C, ZHANG Y Q. Characteristics of decomposition, nutrient release and structure change of wheat straw in a fluvo-aquic soil under different nitrogen application rates. Journal of Plant Nutrition and Fertilizers, 2020, 26(9): 1565-1577. (in Chinese)
[41]	崔娇娇. 氮肥施用对不同类型土壤无机碳转化特性研究[D]. 杨凌: 西北农林科技大学, 2022.
	CUI J J. Characterization of soil inorganic carbon transformation in different types of soils under N fertilizer application[D]. Yangling: Northwest A & F University, 2022. (in Chinese)
[42]	梁超, 朱雪峰. 土壤微生物碳泵储碳机制概论. 中国科学: 地球科学, 2021, 51(5): 680-695.
	LIANG C, ZHU X F. The soil microbial carbon pump as a new concept for terrestrial carbon sequestration. Scientia Sinica (Terrae), 2021, 51(5): 680-695. (in Chinese)
[43]	刘红梅, 李睿颖, 高晶晶, 朱平, 路杨, 高洪军, 张贵龙, 张秀芝, 彭畅, 杨殿林. 保护性耕作对土壤团聚体及微生物学特性的影响研究进展. 生态环境学报, 2020, 29(6): 1277-1284. doi: 10.16258/j.cnki.1674-5906.2020.06.025
	LIU H M, LI R Y, GAO J J, ZHU P, LU Y, GAO H J, ZHANG G L, ZHANG X Z, PENG C, YANG D L. Research progress on the effects of conservation tillage on soil aggregates and microbiological characteristics. Ecology and Environmental Sciences, 2020, 29(6): 1277-1284. (in Chinese)
[44]	LEIFHEIT E F, VERESOGLOU S D, LEHMANN A, RILLIG M C. Multiple factors influence the role of Arbuscular mycorrhizal fungi in soil aggregation—a meta-analysis. Plant and Soil, 2014, 374(1): 523-537. doi: 10.1007/s11104-013-1899-2
[45]	SIX J, PAUSTIAN K, ELLIOTT E T, COMBRINK C. Soil structure and organic matter I. distribution of aggregate-size classes and aggregate-associated carbon. Soil Science Society of America Journal, 2000, 64(2): 681-689. doi: 10.2136/sssaj2000.642681x
[46]	任凤玲. 不同施肥下我国典型农田土壤有机碳固定特征及驱动因素[D]. 北京: 中国农业科学院, 2021.
	REN F L. Soil carbon sequestration and its driving factors under different fertilization in arable land of China[D]. Beijing: Chinese Academy of Agricultural Sciences, 2021. (in Chinese)

项目 Item	小麦产量 Wheat yield	碳投入量 CI	碳储量 SOC_S	固碳速率 SOC_SR	固碳效率SOC_SE	微生物量碳 MBC	可溶性有机碳 DOC	易氧化碳 EO	平均重量直径 MWD	几何平均直径 GMD
秸秆还田 Straw returning (S)	0.002^NS	14511^**	5.5^NS	5.5^NS	22.3^**	8.5^**	0.6^NS	1.8^NS	2.2^NS	1.9^NS
氮肥用量 N rate (N)	47.2^**	36.3^**	6.4^*	6.4^*	4.4^**	45.6^**	6.5^**	4.3^*	13.1^**	14^**
N╳S	1.4^NS	1.1^NS	0.5^NS	0.5^NS	1.3^NS	1.1^NS	0.12^NS	0.5^NS	6.6^**	3.2^NS

处理 Treatment	有机碳储量 SOCs (t·hm^-2)	固碳量 ∆SOCs( t·hm^-2)	固碳速率 SOC_SR (kg·hm^-2·a^-1)	固碳效率 SOC_SE (%)
N0	30.0 b	3.6 b	331.0 b	8.2 bc
N168	31.9 ab	5.5 ab	501.4 ab	11.6 ab
N336	33.2 a	6.8 a	620.1 a	14.3 a
S+N0	31.7 ab	5.3 ab	480.7 ab	7.0 c
S+N168	32.7 a	6.3 a	575.6 a	7.8 bc
S+N336	33.5 a	7.1 a	646.8 a	8.8 bc

处理 Treatment	可溶性有机碳/总有机碳 DOC/SOC (%)	微生物熵 MBC/SOC (%)	易氧化有机碳/总有机碳 EO/SOC (%)
N0	1.6 b	1.2 a	25.6 a
N168	1.7 ab	1.0 ab	27.1 a
N336	1.8 ab	0.8 b	26.4 a
S+N0	1.5 b	1.3 a	26.5 a
S+N168	1.7 ab	1.0 ab	26.7 a
S+N336	1.9 a	0.9 ab	27.0 a

项目 Item	处理 Treatment	团聚体大小 Aggregate size (mm)
项目 Item	处理 Treatment	>2	2-1	1-0.5	0.5-0.25	<0.25
团聚体组成 Aggregate composition (%)	N0	7.7 b	10.0 c	21.8 c	18.7 a	41.9 a
	N168	9.4 ab	12.3 b	30.0 ab	18.0 ab	33.3 c
	N336	8.2 b	12.0 bc	26.3 ab	19.8 a	33.8 bc
	S+N0	7.8 b	11.0 bc	23.9 bc	18.5 a	38.9 ab
	S+N168	8.1 b	12.9 b	27.2 a	18.5 a	33.3 c
	S+N336	11.8 a	15.7 a	28.7 a	15.7 b	29.7 c
团聚体有机碳含量 SOC of aggregates (g·kg^-1)	N0	13.7 ab	13.5 b	12.9 ab	11.0 ab	11.1 ab
	N168	12.8 b	13.7 ab	12.4 ab	10.6 b	11.0 b
	N336	14.61 a	14.0 ab	12.1 b	10.5 b	10.7 b
	S+N0	14.1 ab	14.1 ab	12.9 ab	10.8 ab	10.7 b
	S+N168	14.4 a	14.0 ab	13.2 a	11.4 a	11.6 ab
	S+N336	15.2 a	14.7 a	13.0 a	11.1 ab	12.1 a
团聚体有机碳分布 Distribution percentage of SOC in aggregates (%)	N0	9.1 b	11.2 c	23.4 c	17.1 a	39.1 a
	N168	10.2 ab	14.3 b	28.3 ab	16.1 a	31.1 bc
	N336	10.1b	14.2 b	27.3 ab	17.7 a	30.7 bc
	S+N0	9.2 b	12.9 bc	26.0 b	16.7 a	35.1 ab
	S+N168	9.4 b	14.3 b	28.6 a	16.8 a	30.8 bc
	S+N336	13.5 a	17.5 a	28.3 a	13.3 b	27.3 c