长期施有机肥和化肥对潮土胡敏酸结构特征的影响
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摘要
以河南封丘长期肥料试验为平台,选择有机肥(OM)、化肥NPK(NPK)和不施肥(CK)3种处理,研究了不同施肥措施对潮土胡敏酸(HA)结构特征的影响。HA样品经提取纯化后,采用一系列固态~(13)C核磁共振(NMR)技术并结合元素分析和稳定碳同位素(δ~(13)C)技术对其结构进行定量表征。其中NMR技术包括高速多重倾斜幅度交叉极化/魔角自旋(multiCP/MAS)、偶极相移、化学位移各向异性过滤和质子碳编辑技术。结果表明:长期施有机肥和NPK肥增加了HA的饱和程度、氧化程度和极性,但缩合程度降低;HA的δ~(13)C值降低,表明有新的有机碳进入HA中。潮土HA以脂肪族化合物为主,烷基比例最高,占全碳的24.1%~26.3%;δ64~44处同时存在含氮烷基和甲氧基,且含氮烷基比例更高;另外异头碳和烷氧基中的非质子碳比例均很低。HA的芳香族成分中,δ142~113芳香碳以质子碳为主,且有少量质子芳香碳存在于δ113~93。结果还表明施肥均降低了HA的羧基和δ142~113芳香碳比例,增加了烷氧基和甲氧基比例;施有机肥还增加了酚碳和含氮烷基比例,降低了烷基比例。本研究表明长期施用有机肥和NPK肥使潮土HA结构向着疏水性程度和分解程度降低的方向发展;OM和NPK处理均使糖类物质增加,OM处理还使木质素和多肽增加,脂类物质降低。不同施肥模式下HA的形成机制不同。
【Objective】Fertilization has become increasingly common to increase soil organic matter(SOM) content and improve soil fertility. Research suggests that fertilization promotes production of humic acids( HAs),one of the most important component of SOM. However little is known about the quantitative effects of fertilization on structural characteristics of HAs. Based on the long-term field fertilization experiment in Fegnqiu of Henan,effects of application of organic manure( OM),chemical fertilizer( NPK) and nothing(CK) on structure of HAs in fluvo-aquic soil were assessed.【Method】Soil samples were collected from the surface soil layers of three treatment plots, i.e. OM, NPK and CK, of a long-term winter wheat(Triticumaestivum L.)-summer maize(Zea mays L.) rotation experiment in Fengqiu, China. HAs were exhaustively extracted from the soil samples with a combined 0.1 mol L~(-1) NaOH and 0.1 mol L~(-1) Na_4P_2O_7solution and obtained through precipitation after acidification with 6 mol L~(-1) HCl. HF:HCl(1%:1%)solution was then used to purify the HAs obtained. In the end, the purified HAs were characterized with advanced solid-state ~(13)C nuclear magnetic resonance( NMR) spectroscopy coupled with elemental analysis and isotopic analysis(δ~(13)C). The NMR techniques included multiple cross-polarization/magic angle spinning(multiCP/MAS),dipolar-dephasing( DD),chemical-shift-anisotropy( CSA) filter and spectral editing of immobile CH_2 and CH.【Result】 Results show that long-term fertilization changed the element compositions,δ~(13)C ratios and carbon functional groups of HAs, particularly significant in Treatment OM,and increased saturation degree, oxidation degree and polarity of HAs, but decreased condensation degree of HAs. The decrease of HAs in δ~(13)C values indicated incorporation of new organic carbon into HAs. Advanced NMR techniques revealed that HAs in fluvo-aquic soil were composed predominantly of aliphatic compounds with alkyl being the highest in percentage( 24.1%~26.3%).0CH_3 and NCH signals both resonated aroundδ64~44,while the latter was prominent in proportion. Besides, the proportion of nonprotonated carbon was very low in anomeric and 0-alkyl. Among the aromatics of HAs, they were dominated with protonated carbon in δ142~113,while only a little aromatic carbon existed in δ113~93, which cannot be detected with the routine cross-polarization/magic angle spinning(CP/MAS) NMR. It was also found that long-term fertilization reduced the percentages of COO/N-C=O and aromatic carbon of δ142~113,but increased the percentages of O-alkyl and OCH_3. Moreover, application of organic manure also increased the proportions of aromatic C—O and NCH, but decreased that of alkyl.【Conclusion】In conclusion, all the findings in this study indicate that HA structure tends to be less hydrophobic with decreasing degree of decomposition. The application of either OM or NPK increases the content of carbohydrates in HAs. The application of OM also increases the contents of lignin and peptides, but decreases the content of lipids. The study also suggests that the advanced NMR techniques could provide great insight into HA structure and mechanisms of HA formation relative to fertilization pattern.
【Objective】Fertilization has become increasingly common to increase soil organic matter(SOM) content and improve soil fertility. Research suggests that fertilization promotes production of humic acids( HAs),one of the most important component of SOM. However little is known about the quantitative effects of fertilization on structural characteristics of HAs. Based on the long-term field fertilization experiment in Fegnqiu of Henan,effects of application of organic manure( OM),chemical fertilizer( NPK) and nothing(CK) on structure of HAs in fluvo-aquic soil were assessed.【Method】Soil samples were collected from the surface soil layers of three treatment plots, i.e. OM, NPK and CK, of a long-term winter wheat(Triticumaestivum L.)-summer maize(Zea mays L.) rotation experiment in Fengqiu, China. HAs were exhaustively extracted from the soil samples with a combined 0.1 mol L~(-1) NaOH and 0.1 mol L~(-1) Na_4P_2O_7solution and obtained through precipitation after acidification with 6 mol L~(-1) HCl. HF:HCl(1%:1%)solution was then used to purify the HAs obtained. In the end, the purified HAs were characterized with advanced solid-state ~(13)C nuclear magnetic resonance( NMR) spectroscopy coupled with elemental analysis and isotopic analysis(δ~(13)C). The NMR techniques included multiple cross-polarization/magic angle spinning(multiCP/MAS),dipolar-dephasing( DD),chemical-shift-anisotropy( CSA) filter and spectral editing of immobile CH_2 and CH.【Result】 Results show that long-term fertilization changed the element compositions,δ~(13)C ratios and carbon functional groups of HAs, particularly significant in Treatment OM,and increased saturation degree, oxidation degree and polarity of HAs, but decreased condensation degree of HAs. The decrease of HAs in δ~(13)C values indicated incorporation of new organic carbon into HAs. Advanced NMR techniques revealed that HAs in fluvo-aquic soil were composed predominantly of aliphatic compounds with alkyl being the highest in percentage( 24.1%~26.3%).0CH_3 and NCH signals both resonated aroundδ64~44,while the latter was prominent in proportion. Besides, the proportion of nonprotonated carbon was very low in anomeric and 0-alkyl. Among the aromatics of HAs, they were dominated with protonated carbon in δ142~113,while only a little aromatic carbon existed in δ113~93, which cannot be detected with the routine cross-polarization/magic angle spinning(CP/MAS) NMR. It was also found that long-term fertilization reduced the percentages of COO/N-C=O and aromatic carbon of δ142~113,but increased the percentages of O-alkyl and OCH_3. Moreover, application of organic manure also increased the proportions of aromatic C—O and NCH, but decreased that of alkyl.【Conclusion】In conclusion, all the findings in this study indicate that HA structure tends to be less hydrophobic with decreasing degree of decomposition. The application of either OM or NPK increases the content of carbohydrates in HAs. The application of OM also increases the contents of lignin and peptides, but decreases the content of lipids. The study also suggests that the advanced NMR techniques could provide great insight into HA structure and mechanisms of HA formation relative to fertilization pattern.
引文
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[5]朱青藤,申连玉,钱黎慧,等.有机物料对白土土壤胡敏酸结构特征的影响.植物营养与肥料学报,2015,21(2):396—403Zhu Q T,Shen L Y,Qian L H,et al.Effects of organic material application on the structures of humic acids in low yield paddy soil(In Chinese).Journal of Plant Nutrition and Fertilizer,2015,21(2):396—403
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[7]Mao J D,Olk D C,Fang X W,et al.Influence of animal manure application on the chemical structures of soil organic matter as investigated by advanced solidstate NMR and FT-IR spectroscopy.Geoderma,2008,146(1):353—362
[8]Dou S,Zhang J J,Li K.Effect of organic matter applications on~(13)C-NMR spectra of humic acids of soil.European Journal of Soil Science,2008,59(3):532—539
[9]Jindo K,Hernandez T,Garcia C,et al.Influence of stability and origin of organic amendments on humification in semiarid soils.Soil Science Society of America Journal,2011,75(6):2178—2187
[10]孟安华,吴景贵.不同处理牛粪对植菜土壤腐殖质结构特征的影响.水土保持学报,2015,29(4):223—228,266Meng A H,Wu J G.Effects of different cow dung treatments on humus structure of vegetable planting soil(In Chinese).Journal of Soil and Water Conservation,2015,29(4):223—228,266
[11]赵楠,吕贻忠.不同施肥处理对潮土胡敏酸结构特性的影响.光谱学与光谱分析,2012,32(7):1856—1859Zhao N,Lii Y Z.Effects of different fertilization treaments on soil humic acid sturcture characteristics(In Chinese).Spectroscopy and Spectral Analysis,2012,32(7):1856—1859
[12]Veum K S,Goyne K W,Kremer R J,et al.Biological indicators of soil quality and soil organic matter characteristics in an agricultural management continuum.Biogeochemistry,2014,117(1):81—99
[13]Yan X,Zhou H,Zhu Q H,et al.Carbon sequestration efficiency in paddy soil and upland soil under longterm fertilization in southern China.Soil&Tillage Research,2013,130:42—51
[14]Kelleher B P,Simpson A J.Humic substances in soils:Are they really chemically distinct?Environmental Science&Technology,2006,40(15):4605—4611
[15]Lehmann J,Kleber M.The contentious nature of soil organic matter.Nature,2015,528(7580):60—68
[16]窦森,李艳,关松,等.腐殖物质特异性及其产生机制.土壤学报,2016,53(4):1—11Dou S,Li Y,Guan S,et al.The structural distinctiveness of humic substances and its formation mechanism in simulated incubation(In Chinese).Acta Pedologica Sinica,2016,53(4):1—11
[17]Mao J D,Tremblay L,Gagne J-P.Structural changes of humic acids from sinking organic matter andsurface sediments investigated by advanced solidstate NMR:Insights into sources,preservation and molecularly uncharacterized components.Geochimica et Cosmochimica Acta,2011,75(24):7864—7880
[18]Johnson R L,Schmidt-Rohr K.Quantitative solid-state~(13)C NMR with signal enhancement by multiple cross polarization.Journal of Magnetic Resonance,2014,239:44—49
[19]Gao H J,Chen X,Wei J L,et al.Decomposition dynamics and changes in chemical composition of wheat straw residue under anaerobic and aerobic conditions.PLoS ONE,2016,11(7):e0158172
[20]Zhang D N,Ran Y,Cao X Y,et al.Biosorption of nonylphenol by pure algae,field-collected planktons and their fractions.Environmental Pollution,2015,198:61—69
[21]Xu J,Zhao B,Chu W,et al.Chemical nature of humic substances in two typical Chinese soils(upland vs paddy soil):A comparative advanced solid state NMR study.Science of the Total Environment,2017,576:444—452
[22]Preston C M,Hempfling R,Schulten H R,et al.Characterization of organic-matter in a forest soil of coastal British-Columbia by NMR and pyrolysis-field ionization mass-spectrometry.Plant and Soil,1994,158(1):69—82
[23]张晋京,窦森,张大军.长期施肥对土壤有机质δ~(13)C值影响的初步研究.农业环境科学学报,2006,25(2):382—387Zhang J J,Dou S,Zhang D J.Preliminary study of impact of long-term fertilization onδ~(13)C values of soil organic matter(In Chinese).Journal of AgroEnvironment Science,2006,25(2):382—387
[24]窦森,张晋京,Lichtfouse E,等.用δ~(13)C方法研究玉米秸秆分解期间土壤有机质数量动态变化.土壤学报,2003,40(3):328—334Dou S,Zhang J J,Lichtfouse E,et al.Study ondynamic change of soil organic matter during corn stalk decomposition by 8 13C method(In Chinese).Acta Pedologica Sinica,2003,40(3):328—334
[25]Xin X L,Zhang J B,Zhu A N,et al.Effects of long-term(23 years)mineral fertilizer and compost application on physical properties of fluvo-aquic soil in the North China Plain.Soil&Tillage Research,2016,156:166—172
[26]Spaccini R,Piccolo A,Haberhauer G,et al.Transformation of organic matter from maize residues into labile and humic fractions of three European soils as revealed by~(13)C distribution and CPMAS-NMR spectra.European Journal of Soil Science,2000,51(4):583—594
[27]Garcfa A C,de Souza L G A,Pereira M G,et al.Structure-property-function relationship in humic substances to explain the biological activity in plants.Scientific Reports,2016,DOI:10.1038/srep20798
[28]Cao X Y,Olk D C,Chappell M,et al.Solid-state NMR analysis of soil organic matter fractions from integrated physical-chemical extraction.Soil Science Society of America Journal,2011,75(4):1374—1384
[29]郭素春,郁红艳,朱雪竹,等.长期施肥对潮土团聚体有机碳分子结构的影响.土壤学报,2013,50(5):922—930Guo S C,Yu H Y,Zhu X Z,et al.Effect of long-term fertilization on molecular structure of organic carbon in soil aggregates in fluvo-aquic soil(In Chinese).Acta Pedologica Sinica,2013,50(5):922—930
[30]Kogel-Knabner I.The macromolecular organic composition of plant and microbial residues as inputs to soil organic matter.Soil Biology&Biochemistry,2002,34(2):139—162
[31]Zhang H J,Ding W X,Yu H Y,et al.Linking organic carbon accumulation to microbial community dynamics in a sandy loam soil:Result of 20 years compost and inorganic fertilizers repeated application experiment.Biology and Fertility of Soils,2015,51(2):137—150
[2]吴景贵,任军,赵欣宇,等.不同培肥方式黑土腐殖质形态特征研究.土壤学报,2014,51(4):709—717WuJG,Ren J,Zhao X Y,et al.Morphology of humus in black soil as affected by fertilization method(In Chinese).Acta Pedologica Sinica,2014,51(4):709—717
[3]张奇春,王光火.施用化肥对土壤腐殖质结构特征的影响.土壤学报,2006,43(4):617—623Zhang Q C,Wang G H.Effect of chemical fertilizer on structure of soil humus(In Chinese).Acta Pedologica Sinica,2006,43(4):617—623
[4]窦森.土壤有机质.北京:科学出版社,2010Dou S.Soil organic matter(In Chinese).Beijing:Science Press,2010
[5]朱青藤,申连玉,钱黎慧,等.有机物料对白土土壤胡敏酸结构特征的影响.植物营养与肥料学报,2015,21(2):396—403Zhu Q T,Shen L Y,Qian L H,et al.Effects of organic material application on the structures of humic acids in low yield paddy soil(In Chinese).Journal of Plant Nutrition and Fertilizer,2015,21(2):396—403
[6]Chien S W C,Wang M C,Hsu J H,et al.Influence of fertilizers applied to a paddy-upland rotation oncharacteristics of soil organic carbon and humic acids.Journal of Agricultural and Food Chemistry,2006,54(18):6790—6799
[7]Mao J D,Olk D C,Fang X W,et al.Influence of animal manure application on the chemical structures of soil organic matter as investigated by advanced solidstate NMR and FT-IR spectroscopy.Geoderma,2008,146(1):353—362
[8]Dou S,Zhang J J,Li K.Effect of organic matter applications on~(13)C-NMR spectra of humic acids of soil.European Journal of Soil Science,2008,59(3):532—539
[9]Jindo K,Hernandez T,Garcia C,et al.Influence of stability and origin of organic amendments on humification in semiarid soils.Soil Science Society of America Journal,2011,75(6):2178—2187
[10]孟安华,吴景贵.不同处理牛粪对植菜土壤腐殖质结构特征的影响.水土保持学报,2015,29(4):223—228,266Meng A H,Wu J G.Effects of different cow dung treatments on humus structure of vegetable planting soil(In Chinese).Journal of Soil and Water Conservation,2015,29(4):223—228,266
[11]赵楠,吕贻忠.不同施肥处理对潮土胡敏酸结构特性的影响.光谱学与光谱分析,2012,32(7):1856—1859Zhao N,Lii Y Z.Effects of different fertilization treaments on soil humic acid sturcture characteristics(In Chinese).Spectroscopy and Spectral Analysis,2012,32(7):1856—1859
[12]Veum K S,Goyne K W,Kremer R J,et al.Biological indicators of soil quality and soil organic matter characteristics in an agricultural management continuum.Biogeochemistry,2014,117(1):81—99
[13]Yan X,Zhou H,Zhu Q H,et al.Carbon sequestration efficiency in paddy soil and upland soil under longterm fertilization in southern China.Soil&Tillage Research,2013,130:42—51
[14]Kelleher B P,Simpson A J.Humic substances in soils:Are they really chemically distinct?Environmental Science&Technology,2006,40(15):4605—4611
[15]Lehmann J,Kleber M.The contentious nature of soil organic matter.Nature,2015,528(7580):60—68
[16]窦森,李艳,关松,等.腐殖物质特异性及其产生机制.土壤学报,2016,53(4):1—11Dou S,Li Y,Guan S,et al.The structural distinctiveness of humic substances and its formation mechanism in simulated incubation(In Chinese).Acta Pedologica Sinica,2016,53(4):1—11
[17]Mao J D,Tremblay L,Gagne J-P.Structural changes of humic acids from sinking organic matter andsurface sediments investigated by advanced solidstate NMR:Insights into sources,preservation and molecularly uncharacterized components.Geochimica et Cosmochimica Acta,2011,75(24):7864—7880
[18]Johnson R L,Schmidt-Rohr K.Quantitative solid-state~(13)C NMR with signal enhancement by multiple cross polarization.Journal of Magnetic Resonance,2014,239:44—49
[19]Gao H J,Chen X,Wei J L,et al.Decomposition dynamics and changes in chemical composition of wheat straw residue under anaerobic and aerobic conditions.PLoS ONE,2016,11(7):e0158172
[20]Zhang D N,Ran Y,Cao X Y,et al.Biosorption of nonylphenol by pure algae,field-collected planktons and their fractions.Environmental Pollution,2015,198:61—69
[21]Xu J,Zhao B,Chu W,et al.Chemical nature of humic substances in two typical Chinese soils(upland vs paddy soil):A comparative advanced solid state NMR study.Science of the Total Environment,2017,576:444—452
[22]Preston C M,Hempfling R,Schulten H R,et al.Characterization of organic-matter in a forest soil of coastal British-Columbia by NMR and pyrolysis-field ionization mass-spectrometry.Plant and Soil,1994,158(1):69—82
[23]张晋京,窦森,张大军.长期施肥对土壤有机质δ~(13)C值影响的初步研究.农业环境科学学报,2006,25(2):382—387Zhang J J,Dou S,Zhang D J.Preliminary study of impact of long-term fertilization onδ~(13)C values of soil organic matter(In Chinese).Journal of AgroEnvironment Science,2006,25(2):382—387
[24]窦森,张晋京,Lichtfouse E,等.用δ~(13)C方法研究玉米秸秆分解期间土壤有机质数量动态变化.土壤学报,2003,40(3):328—334Dou S,Zhang J J,Lichtfouse E,et al.Study ondynamic change of soil organic matter during corn stalk decomposition by 8 13C method(In Chinese).Acta Pedologica Sinica,2003,40(3):328—334
[25]Xin X L,Zhang J B,Zhu A N,et al.Effects of long-term(23 years)mineral fertilizer and compost application on physical properties of fluvo-aquic soil in the North China Plain.Soil&Tillage Research,2016,156:166—172
[26]Spaccini R,Piccolo A,Haberhauer G,et al.Transformation of organic matter from maize residues into labile and humic fractions of three European soils as revealed by~(13)C distribution and CPMAS-NMR spectra.European Journal of Soil Science,2000,51(4):583—594
[27]Garcfa A C,de Souza L G A,Pereira M G,et al.Structure-property-function relationship in humic substances to explain the biological activity in plants.Scientific Reports,2016,DOI:10.1038/srep20798
[28]Cao X Y,Olk D C,Chappell M,et al.Solid-state NMR analysis of soil organic matter fractions from integrated physical-chemical extraction.Soil Science Society of America Journal,2011,75(4):1374—1384
[29]郭素春,郁红艳,朱雪竹,等.长期施肥对潮土团聚体有机碳分子结构的影响.土壤学报,2013,50(5):922—930Guo S C,Yu H Y,Zhu X Z,et al.Effect of long-term fertilization on molecular structure of organic carbon in soil aggregates in fluvo-aquic soil(In Chinese).Acta Pedologica Sinica,2013,50(5):922—930
[30]Kogel-Knabner I.The macromolecular organic composition of plant and microbial residues as inputs to soil organic matter.Soil Biology&Biochemistry,2002,34(2):139—162
[31]Zhang H J,Ding W X,Yu H Y,et al.Linking organic carbon accumulation to microbial community dynamics in a sandy loam soil:Result of 20 years compost and inorganic fertilizers repeated application experiment.Biology and Fertility of Soils,2015,51(2):137—150