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1.
川南地区不同退耕地对土壤抗蚀性的影响 总被引：5，自引：2，他引：3
对川南坡地退耕5年后的慈竹林地、杂交竹林地、桤木+慈竹混交林地和弃耕地土壤抗蚀性变化进行了研究,探讨了土壤抗蚀性指标间的关系。结果表明:退耕后土壤水稳性团聚体平均质量直径、结构性颗粒指数、团聚状况、团聚度、物理稳定性指数和有机质增加,土壤结构体破坏率、不稳定团粒指数、分散率、侵蚀系数和受蚀性指数降低;各退耕地土壤抗蚀性综合主成分值为-4.466~3.436,呈现出慈竹林地杂交竹林地桤木+慈竹混交林地弃耕地对照的特点;土壤有机质与大多数抗蚀性指标具有显著相关性,且与抗蚀性综合主成分值呈极显著正相关,说明坡地退耕后土壤有机质增加是土壤抗蚀性增强的关键,坡地退耕成慈竹林地更有利于增强研究区土壤抗蚀性。 相似文献
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沈阳市郊玉米连作土壤有机质组成及其对土壤结构的影响 总被引：3，自引：0，他引：3
通过对沈阳市郊玉米连作土壤的有机质、结构情况以及二者相互关系研究表明,土壤中有机质大致范围在16.31gkg-1～23.72gkg-1,腐殖质大致范围在15.17gkg-1～21.49gkg-1,非腐殖质大致范围在1.14gkg-1～2.59gkg-1;在腐殖质各组分中,胡敏素的含量最高,约占腐殖质总量的58.93%～66.34%,胡敏酸约占16.26%～22.87%,富里酸约占16.82%～18.20%,胡富比约在0.95～1.32之间;干筛处理后>0.25mm的土壤团聚体占到80%以上,其中以>2mm团聚体为主,湿筛处理后>0.25mm的土壤团聚体仅占20%左右,其中0.25～0.5mm团聚体为主,水稳性系数在17.33%～35.67%。对有机质及其各组分与土壤各级团聚体做的相关分析结果表明,有机质与0.25～5mm粒径组的团聚体呈显著相关,与>5mm团聚体不相关,且胡敏酸主要影响1～5mm大团聚体的形成。 相似文献
3.
长期施肥对小麦-玉米作物系统土壤腐殖质组分碳和氮的影响 总被引：7，自引：1，他引：6
通过对华北平原小麦–玉米轮作农田生态系统18年田间施肥试验,研究了长期不同施肥处理对耕层（0—20 cm）土壤腐殖质及活性腐殖质组分碳和氮的影响。试验设化肥NPK不同组合（NPK、NP、NK、PK）,全部施用有机肥（OM）,一半有机肥+化肥NPK（1/2OMN）及不施肥（CK）共7个处理。结果表明,各施肥处理均能在不同程度上增加土壤腐殖质（胡敏酸、富里酸和胡敏素）及活性腐殖质（活性胡敏酸和活性富里酸）组分碳和氮含量,提高可浸提腐殖质（胡敏酸和富里酸）及活性腐殖质组分碳和氮分配比例;但施肥对土壤活性腐殖质组分碳和氮含量的增加率均分别高于腐殖质组分碳和氮。各处理土壤腐殖质及活性腐殖质组分碳和氮含量均为OM处理最高,且有机肥与化肥NPK配施高于单施化肥各处理;而化肥处理中NPK均衡施用效果最好。说明施用有机肥、有机肥与化肥NPK配施及化肥NPK均衡施用是增加土壤腐殖质及活性腐殖质组分碳和氮的关键;活性腐殖质组分碳和氮较腐殖质组分碳和氮对施肥措施的响应更灵敏。 相似文献
4.
侵蚀红壤腐殖酸组分特点及其对水稳性团聚体的影响 总被引：5，自引：0，他引：5
在华中地区采集不同侵蚀程度(轻度、中度、严重)的红壤,利用干湿筛法获得不同粒径的水稳性团聚体(0.25 mm)。通过测定不同粒径水稳性团聚体(0.25 mm)的腐殖酸组分(胡敏酸和富里酸)碳量,以及向不同侵蚀程度的各粒径团聚体(0.25 mm)中添加不同浓度(0.06、0.6 g L-1)的胡敏酸,分析侵蚀红壤腐殖酸组分特点及其对水稳性团聚体的影响。结果表明:随着侵蚀程度的增加,供试红壤和水稳性团聚体(0.25 mm)的腐殖酸组分含量减少;轻度和中度侵蚀红壤中,大粒径(4和2~4 mm)水稳性团聚体的胡敏酸碳量较小粒径(1~2、0.5~1和0.25~0.5 mm)的高;同种侵蚀程度下,除严重侵蚀红壤中2~4 mm团聚体的富里酸碳量与1~2 mm团聚体中的有显著差异外,不同粒径团聚体中富里酸碳量差别不大。3种侵蚀程度红壤的胡富比总体上小于1,其中中度侵蚀红壤和各粒径水稳性团聚体的胡富比均大于其他两种侵蚀程度的。腐殖酸组分与水稳性团聚体(0.25 mm)含量呈极显著正相关,与胡敏酸碳量的相关系数最大(r=0.85**,n=19)。添加不同浓度(0.06和0.6 g L-1)胡敏酸后,3种侵蚀程度红壤各粒径水稳性团聚体(0.25 mm)的含量均增加,且小粒径团聚体(1~2、0.5~1和0.25~0.5 mm)的增加量要高于大团聚体(2~4、4 mm)的。 相似文献
5.
【目的】研究免耕条件下，长期采用不同的土壤覆盖方式及配合施用生物炭对渭北旱塬农田土壤团聚体稳定性和腐殖质性质的影响，为选择适合的耕作管理措施提供理论依据。【方法】基于连续18年田间定位试验，选择其中免耕条件下的无覆盖(NT)、施用生物炭(NB)、秸秆覆盖(NS)、地膜覆盖(NP)、秸秆地膜二元覆盖(NSP) 5个处理，采集0—10、10—20 cm土层土壤样品，通过干筛+湿筛法分为粉黏粒(<0.053 mm)、微团聚体(0.053～0.25 mm)、细大团聚体(0.25～2 mm)、粗大团聚体(>2 mm)共4个团聚体粒级，并测定了各粒级团聚体中有机碳和腐殖质组分含量。【结果】1)与NT处理相比，NS处理各粒径团聚体胡敏酸含量(0.93%～92.6%)和富里酸含量(1.8%～327.5%)显著增加且增幅最大，NSP处理各粒径团聚体有机碳含量显著提高了1.6%～30.5%;NB处理各粒径团聚体有机碳含量(39.90%～161.8%)及胡敏素含量的增幅最大，0—10 cm土层胡敏素含量显著提高了87.2%～271.7%。与NT相比，NS、NSP和NB处理均提高了土壤团聚体的稳定... 相似文献
6.
为探究生物炭对土壤腐殖质组成和团聚体特征的影响，以东北黑土区植烟土壤为研究对象，设置了3个处理，2019-2020年连续施用低量生物炭5t/hm2（C1）；高量生物炭25t/hm2（C2）和不施生物炭（CK），分析了不同用量生物炭对土壤腐殖质组分及水稳性团聚体分布的影响，并利用傅里叶红外光谱(FTIR)和13C核磁共振光谱(13C-NMR)对土壤胡敏酸化学结构进行表征。结果表明：C1和C2处理分别使富里酸减少了16.90%和40.85%，胡敏酸含量显著增加了14.86%和33.78%，胡敏酸在腐殖酸中所占比例（PQ值）也显著增加；FTIR和13C-NMR分析表明，C2处理的土壤胡敏酸的2920/1620值降低了11.82%，脂族C/芳香C比值降低了13.04%，表明高量生物炭使胡敏酸芳构化程度增强，脂肪结构比例降低；生物炭的添加促使土壤大团聚体（>0.25mm）比例增加，C2处理提升大团聚体的作用更显著。结合相关性分析发现，胡敏酸含量与2~0.25mm大团聚体含量显著正相关，胡敏酸分子的脂肪族官能团特征与>2mm粒级团聚体显著正相关。此外，C1和C2处理显著提高了烟叶产量。从而表明，生物炭能提升土壤腐殖质中胡敏酸含量和结构，有利于土壤大团聚体形成，提高土壤固碳潜力，对作物有一定的增产效果。 相似文献
7.
[目的]分析祁连山浅山区退耕地土壤团聚体及其有机碳和全氮分布特征,为该区退耕地植被恢复及水土流失防治提供理论依据。[方法]以祁连山大黄山林区三种类型退耕地为研究对象,通过干筛法测定团聚体粒径,分析不同粒级团聚体组成及其有机碳和全氮分布规律。[结果] 3种类型退耕地≥0.25 mm的大团聚体含量高于0.25 mm的微团聚体,其中以5 mm和0.25～2 mm粒级团聚体为主;封育草地团聚体稳定性最强,平均重量直径(MWD)高于沙棘林地9.31%,高于未封育草地31.95%;未封育草地土壤有机碳含量低于沙棘林地和封育草地,且差异显著,三种类型退耕地土壤全氮含量没有明显变化趋势;0.25～2 mm团聚体有机碳含量最高,0.25 mm微团聚体全氮含量最高,沙棘林地和封育草地土壤团聚体养分优于未封育草地;与团聚体分布特征相同,5 mm和0.25～2 mm粒级团聚体依然是退耕地有机碳和全氮储存的主体。[结论]祁连山浅山区退耕地以≥0.25 mm的大团聚体为主,沙棘林地和封育草地团聚体稳定性及其有机碳和全氮含量高于未封育草地。 相似文献
8.
采用野外调查与室内分析相结合的方法,研究了"三江并流区"5个典型暗棕壤剖面腐殖质特性及其与土壤结构的关系,以期为该区土地资源的保护提供有利依据.结果表明,腐殖质含量与有机碳的分布规律一致,即腐殖质层＞淋溶层＞淀积层＞母质层.腐殖质组成中,以胡敏素(HA)占绝大多数.HA分子复杂程度较高,化学稳定性较强.土壤腐殖化程度与富里酸FA分子复杂程度和化学稳定性一致,随年降雨量的增加而降低,依次为哈巴雪山＞千湖山＞梅里雪山＞云岭＞高黎贡山.1～0.5 mm粒径团聚体含量居多,且粒径含量与腐殖酸含量均随年均温的升高而降低,依次为高黎贡山＞梅里雪山＞千湖山＞哈巴雪山＞云岭.研究结果表明,表层有机碳与1～0.5 mm粒径含量相关,胡敏酸和富里酸与1～0.5,0.5～0.25 mm粒径含量呈显著相关. 相似文献
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10.
长白山不同林型土壤有机碳特征 总被引：2，自引：1，他引：1
采用野外采样与室内分析相结合的方法,研究了长白山北坡6种不同林型(阔叶林、针叶林、云冷杉、岳桦林、岳桦-苔原、高山苔原)土壤有机碳及其组分的含量,分析了土壤有机碳分布与铁铝氧化物和黏粒矿物组成之间的关系。结果表明:不同林型之间,阔叶林土壤的有机碳、胡敏素碳、颗粒有机碳、2~0.25 mm大团聚体碳和0.25~0.053 mm微团聚体碳含量最高,云冷杉土壤的易氧化碳含量最高而水溶性有机碳、胡敏酸碳、富里酸碳和颗粒有机碳含量最低;此外,岳桦林土壤的胡敏酸碳和富里酸碳含量显著高于其他林型土壤,岳桦-苔原土壤的水溶性有机碳含量显著高于其他林型土壤,而高山苔原土壤的有机碳和易氧化碳含量显著低于其他林型土壤。相关性分析表明,土壤有机碳含量与非晶质氧化铝含量呈显著的正相关关系(P<0.05),富里酸碳含量与游离氧化铝含量呈显著的正相关关系(P<0.05),而0.25~0.053 mm微团聚体有机碳含量与2种形态氧化铝含量都呈显著的正相关关系(P<0.05)。上述结果指出,不同林型条件下各有机碳及其组分差异显著。 相似文献
11.
运用野外调查与实验分析相结合的方法,对不同生长发育阶段红松人工林（林龄25、45、58、68 a）和红松混交林（林龄60a）根际与非根际土壤有机质含碳量、腐殖质组成与结合形态进行了研究。结果表明:不同年龄阶段红松人工纯林、红松混交林土壤有机质含碳量、腐殖质各组分含碳量随土层深度的加深而降低,并且根际土壤高于非根际土壤。就土壤腐殖质组成而言,除林龄58a红松人工林根际土壤和45a红松人工林非根际土壤外,其他林型土壤胡敏酸含碳量均高于富里酸含碳量;胡敏酸与富里酸比值（HA/FA）在1.00～2.45之间;土壤重组腐殖质、松结态腐殖质、稳结态腐殖质含碳量大小顺序为林龄58>68>25>45a;红松混交林除紧结态腐殖质外,其他腐殖质各组分含碳量均高于红松人工林。 相似文献
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Humus accumulation, humification, and humic acid composition in soils of two post-mining chronosequences after coal mining 总被引：1，自引：0，他引：1
Evgeniy Vasilyevitch Abakumov Tomáš Cajthaml Jiří Brus Jan Frouz 《Journal of Soils and Sediments》2013,13(3):491-500
Purpose
To assess how the rates of humus formation and humification are affected by land use and age of ecosystems, this study investigated soil development in two post-mining chronosequences (spoil heaps formed from open-cast coal mining near Sokolov, Czech Republic). The following characteristics were measured: content, composition, and properties of humic acids; organic carbon (C) and total nitrogen (N) contents; pH; and amorphous iron content.Materials and methods
Two chronosequences were studied. One consisted of unreclaimed spontaneously revegetated spoils (3, 12, 20, and 40 years old). The other consisted of heaps that were reclaimed by planting alder in graded heaps (7, 15, 20, 30, and 40 years old). Humus and iron contents as well as pH were determined, and humic acids were extracted for detailed chemical analyses (C, H, N, 13C-NMR, and pyrolysis mass-spectrometry).Results and discussion
C and N accumulated faster in the reclaimed sites than in the unreclaimed sites; organic matter accumulation results in the decrease of pH in all soils and in spontaneous sites also increase of amorphous iron content. Humic acids (HA) and fulvic acids (FA) increased with the site age in both chronosequences. The CHA/CFA was higher in the reclaimed soils than in the unreclaimed soils, and the CHA/CFA ratio increased with age in the unreclaimed soils. Humic acid aromaticity was higher in the reclaimed site than in the unreclaimed sites but increased with the age of unreclaimed sites. H and O content decreased with age of reclaimed soils. Humification led to an increase in HA caloricity in the reclaimed sites but not in unreclaimed sites because of the influence of residual wax-type substances in the unreclaimed sites. Degree of HA oxidation (ω) for the reclaimed plots was similar to that in typical zonal soils but was highly variable in unreclaimed soils.Conclusions
Relative to spontaneous revegetation in the unreclaimed sites, reclamation increased the rates of humus accumulation, humification, and humus acid transformations. The differences between reclaimed and unreclaimed sites, however, decreased with site age and were very small in 40-year-old sites. These differences correspond to the rapid colonization of the reclaimed sites and the slow colonization of the unreclaimed sites by soil biota. 相似文献13.
不同退耕模式下土壤抗蚀性差异及其评价模型 总被引：11，自引：3，他引：8
土壤抗蚀性是评定土壤抵抗土壤侵蚀能力的重要参数之一,该文通过野外调查与室内分析相结合方法,在土壤理化性质综合分析的基础上,融入生物学指标,对川西低山丘陵区退耕桉树林、退耕杉木林、退耕茶园、退耕枇杷园和退耕撂荒地5种退耕模式下土壤抗蚀性进行了研究。结果表明：19个用于表征研究区土壤抗蚀性的指标可优化为>0.25 mm水稳性团聚体含量、平均质量直径、>0.25 mm团聚体破坏率、>0.5 mm团聚体破坏率、有机质含量及酸性磷酸酶6个指标;5种退耕模式下土壤抗蚀性综合指数大小依次为退耕杉木林＞退耕桉树林＞退耕枇杷园＞退耕茶园＞退耕撂荒地。在此基础上,应用6个优化指标构建了研究区不同退耕模式下土壤抗蚀性强、中等、弱3个等级的判别模型,模型总判别正确率为96.7%,具有较高的可信度。这为完善不同退耕模式下土壤抗蚀性评价指标体系和区域性土壤抗蚀性评价提供依据。 相似文献
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三江平原典型湿地土壤腐殖质的剖面分布及其组成特征 总被引：10，自引：0，他引：10
以三江平原腹地挠力河、别拉洪河、浓江河流域自然沼泽湿地为研究对象,研究了典型湿地土壤腐殖质的剖面分布及其组成特征,并探讨了土壤腐殖质与植被类型及土壤全氮含量的关系。三江平原典型湿地土壤草根层和泥炭层中胡敏酸(HA)和富里酸(FA)的累计含量在整个剖面总量中的比例均大于70%,各组分相对含量分别高于35%总有机碳和23%总有机碳,其剖面分布与土壤有机碳(SOC)的变化趋势一致,由表层向下层逐渐减少。除小叶章湿地土壤草根层HA/FA值为0.97外,三江平原典型湿地土壤HA/FA均大于1,其剖面均值为1.4~2.5,表明三江平原湿地为胡敏酸型土壤.腐殖质各组份含量及其HA/FA值因植被类型而异,而与土壤全氮含量呈显著线性相关(p<0.05)。 相似文献
15.
Humus composition of soils under forest, coffee and arable cultivation in hilly areas of south Sumatra, Indonesia 总被引：4，自引：0，他引：4
A. Watanabe Sarno J. Rumbanraja K. Tsutsuki & M. Kimura 《European Journal of Soil Science》2001,52(4):599-606
To understand the effect of land use changes on the composition of humus in tropical soils, samples from land under primary forest, secondary forest, coffee plantation, and arable crops were investigated at three sites in south Sumatra, Indonesia. Total carbon and total nitrogen contents were 1.7 to 4.3 times and 1.1 to 2.8 times greater in the topsoil under primary forest than under the other types of land use. Following change from primary forest to other uses, the proportion of humic acids in the organic matter of the topsoils decreased while that of the fulvic acid fraction increased. Within the range of land uses, differences in the yields of humic acids and fulvic acid fractions were, respectively, larger and smaller than those in total carbon content. The humic acids were classified into the low and middle classes in the degree of humification. Absorption due to the green fraction of humic acids, Pg, was detected in the UV‐visible spectra of almost all the humic acids. No relation was observed between the degree of humification of humic acids or the strength of Pg absorption in their spectra and land use change. The fulvic acid fractions were fractionated on insoluble polyvinylpyrrolidone (PVP) into the adsorbed fractions consisting of humic substances and the non‐adsorbed fractions consisting of non‐humic substances. A positive correlation between the amount of the fulvic acid fraction and the percentage of the PVP‐adsorbed fraction within it indicated that the variation in the amount of the fulvic acid fraction was attributable to acid‐soluble humic substances. The ionization difference spectra of solutions between pH 12 and pH 7 suggested that the chemical structures of the PVP‐adsorbed fulvic acids have been altered by land use change. 相似文献
16.
集约经营对山核桃林地土壤腐殖质组分碳含量的影响 总被引：1，自引：0，他引：1
[目的]研究并探讨土壤腐殖质各组分碳含量的变化规律,为山核桃林地土壤管理提供理论依据。[方法]采集并分析山核桃林经营历史为5,10,15,20a的土壤样品的土壤腐殖质各组分碳含量,并与天然混交林(0a)进行比较。[结果]与天然山核桃—阔叶混交林(0a)相比,随着经营历史的延长,林地土壤腐殖质各组分碳含量的变化主要发生在表层(0—10cm),胡敏酸碳、富里酸碳和胡敏素碳含量均下降。与0a相比,集约经营5a后胡敏酸碳、富里酸碳和胡敏素碳含量分别下降了42.8%,23.9%和21.2%,而集约经营20a后,分别下降了45.3%,39.0%,32.3%。集约经营20a后,亚表层(10—30cm)土壤胡敏素碳含量上升了94.2%。[结论]集约经营降低了山核桃林地土壤表层和亚表层的胡敏酸碳和富里酸碳含量,同时也降低了表层土壤胡敏素碳含量,而提高了亚表层土壤胡敏素碳含量。 相似文献
17.
Calcium-bound and iron-and aluminium-bound humus extracted from different soils collected from north to south of China were characterized by chemical and spectroscopic methods.Meaningful differences in the composition and structure between them were revealed by ^13 C NMR,visible spectroscopy and elemental analysis.Results showed that the contents of carbon,hydrogen and nitrogen were higher in iron-and aluminium-bound humus than in calcium-bound humus while oxygen content in calcium-bound humus was shown to be higher .The calcium-bound humus had higher C/N and O/C ratios than iron-and aluminiumbound humus.The calcium-bound humic acid(HA1) showed higher E4/E6 ratios than iron-and aluminumboud,humic acid(HA2)while iron-and aluminum-bound fulvic acid(FA2) showed higher E4/E6 ratios than calcium-bound fulvic acid(FA1).An inverse relationship between E4/E6 ratios and aromaticity as determined by 13C NMR spectra was observerd for HA and FA from black soil.The 13C NMR spectroscopy revealed that HA2 was more aromatic than HA1.On the other ,FA1 exhibited a higher aromaticity than FA2. 相似文献
18.
A volcanic ash soil consisting of more than 40 layers, of volcanic fallout was studied from the standpoint of humus chemistry. According to soil texture and humic acid type, the soil profile was divided into 3 sections as follows: (1) Upper layers formed since 1779 A.D. Loamy sand. Po or A type. (2) Middle layers formed from 1779 A.D. to 5,540 yr. B.P. Sandy loam, A, A or P type. (3) Lower layers formed from 5,540 yr. B.P. to about 20,000 D.P. Sandy clay, loam or clay loam, A± type. The PQ values in the middle layers were lower than those of the upper and lower layers. The distribution of carbon and nitrogen contents in the fulvic and humic acid and humin fractions of each layer varied considerably. The CfN ratio of the total humus of each layer tended to increase with the increase in its carbon content. C/N ratios of humic acids in the lower layers were higher than those in the upper and middle layers. C/N ratios of fulvic acid fractions were nearly constant (10-13), for all layers examined, and those of humin fractions ranged from 15 to 20, with one exception of 34. The amounts of sugars, uronic acids and amino acids in hydrolysates of fulvic acids were more or less same for all samples, and sum of the amounts of carbon in these compounds comprised 30 to 40 percent of fulvic acid carbon. Amino acid nitrogen comprised 72 to 94 percent of fulvic acid nitrogen. Seven amino acids were detected, among which aspartic acid, glutamic acid and glycine were predominant. 相似文献
19.
蜉金龟堆肥施入后土壤腐殖质表征及特性研究 总被引：2，自引：1，他引：1
采用元素组成、红外光谱及差热分析对土壤施用蜉金龟堆肥后腐殖质结构特征的变化进行表征。元素分析结果表明,与对照处理相比,土壤施用蜉金龟堆肥后焦磷酸钠浸提胡敏酸(NaHA)、氢氧化钠浸提胡敏酸(PAHA)、焦磷酸钠浸提富里酸(NaFA)及氢氧化钠浸提富里酸(PAFA)的碳含量增加,H/C减小,表明施肥后土壤腐植酸(胡敏酸和富里酸)的芳香性增加。差热分析结果表明,与NaHA相比,对照处理和施蜉金龟堆肥PAHA的高温放热峰消失,说明PAHA的热稳定性低于NaHA;而NaFA在两种处理中的中温反应热也均高于PAFA,进一步说明了氢氧化钠浸提腐植酸的热稳定性高于焦磷酸钠浸提的腐植酸。红外光谱结果表明,两种提取剂提取的土壤腐植酸均含有大量的芳香化合物和碳水化合物。综上,两种提取剂对土壤腐植酸在热性质及官能团的组成上存在着差异性。 相似文献