有机质对土壤光谱特性的影响研究

为了探明土壤有机质的光谱特征及其影响作用,从而为有机质土壤铁氧化物的定量反演提供理论依据。利用去有机质前后土壤的光谱数据,研究了有机质对土壤反射率、土壤线参数、土壤铁氧化物定量反演的影响。研究结果表明,去除有机质后,能明显提高土壤反射率,变化最明显的为可见光橙黄光波段,即570～630 nm。相关性分析也显示橙黄光波段反射率的相对变化量或差值与有机质去除量之间的相关系数要比其他波段高,相关系数最大值在600 nm。因此,建议采用570～630 nm的光谱数据进行有机质的反演;土壤线斜率在去有机质后明显降低,截距显著增大,二者变化量与有机质去除量呈极显著相关关系,可用土壤线参数预测有机质含量。有机质对铁氧化物的反演具有明显影响,特别是有机质大于20 g kg-1的土壤,在进行反演时应考虑有机质对反演精度的影响,需采取有效地技术手段消减其影响作用,才能达到较好的效果。     

Conservation tillage and depth stratification of porosity and soil organic matter

Pores and organic matter take a multitude of forms in soil and their characteristics change in space and time following a change in tillage practices as a new “steady state” is approached. Information on the variation with depth (stratification) in the characteristics of pores and organic matter and the rates of change in these characteristics is vital to interpreting the short- and long-term impacts of a reduction of tillage on the productivity and hydrology of agricultural soils. This information is also of value in estimating the effect of a reduction in tillage on the sequestration of carbon in agricultural soils. Recent literature comparing conventional tillage (CT) with no-till (NT) in temperate agroecosystems with varying soil textures and climates was reviewed for the purpose of assessing rates of change in the magnitude and stratigraphy of bulk density, porosity, pore size classes, organic matter content and organic matter fractions. The influence of tillage on bulk density, macroporosity and organic matter content was found to be documented more extensively than the effects on pore size distribution, soil organic matter fractions and their interactions at different soil depths. Many of the reports documenting tillage-induced changes in soil porosity and organic matter were based on measurements at a specific time after initiating the tillage trial. Results obtained by different investigators were found to be most consistent when measurements were made ≥15 years after initiating the tillage trial. Data from different studies were used to generalize trends in pore and organic matter characteristics with depth and time. However, few studies provided measurements that permitted accurate prediction of either the rates of change or the maximum change that will occur following a change from CT to NT. Future research must enhance our ability to make these predictions if we wish to garner a better understanding of the effects of NT on the quality and productivity of agricultural soils and their ability to sequester carbon.     

耕作对土壤有机物和土壤团聚体稳定性的影响

Agricultural sustainability relates directly to maintaining or enhancing soil quality. Soil quality studies in Canada during the 1980‘s showed that loss of soil organic matter (SOM) and soil aggregate stability was standard features of non-sustainable land management in agroecosystems. In this study total soil organic carbon (SOC), particulate organic matter (POM), POM-C as a percentage of total SOC, and aggregate stability were determined for three cultivated fields and three adjacent grassland fields to assess the impact of conventional agricultural management on soil quality. POM was investigated using solid-state ^13C nuclear magnetic resonance (NMR) to determine any qualitative differences that may be attributed to cultivation. Results show a highly significant loss in total SOC, POM and aggregate stability in the cultivated fields as compared to the grassland fields and a significant loss of POM-C as a percentage of total SOC.Integrated results of the NMR spectra of the POM show a loss in carbohydrate-C and an increase in aromatic-C in the cultivated fields, which translates to a loss of biological lability in the organic matter. Conventional cultivation decreased the quantity and quality of SOM and caused a loss in aggregate stability resulting in an overall decline in soil quality.     

施用有机肥对土壤团聚体稳定性的影响

施用有机肥是循环农业的典型措施,能够净化环境、保证食品安全、加强土壤的可持续利用。本文以中国农业大学曲周试验站长期设施蔬菜地为研究对象,试验已进行6年,共设单施有机肥、有机无机配施与无机肥3种施肥处理。结果表明:施用有机肥处理的土壤有机C含量显著高于有机无机配施和无机肥处理107.02%、171.71%;干筛分析表明有机肥处理下的土壤非水稳性团聚体的平均重量直径(WMD)和几何平均直径(GMD)值均显著高于有机无机配施与无机肥65.68%、4.18%和16.80%、8.26%;湿筛结果也表明有机肥处理下的土壤水稳性团聚体WMD、GMD值显著高于有机无机配施与无机肥41.12%、34.78%和77.78%、63.16%;0~20 cm耕层有机肥处理增加了土壤分散系数,而20~40 cm耕层有机肥处理显著降低了土壤分散系数。在蔬菜有机栽培中单施有机肥可增加土壤有机C、非水稳性团聚体、水稳性团聚体及耕层下微团聚体含量,是改良土壤结构的有效措施。     

Effects of organic matter and calcium on soil structural stability

The cationic bridging effect of the calcium ion (Ca²⁺) and the flocculating ability of clay and organic matter are crucial in the formation and stability of soil aggregates. They are therefore likely to influence the soil's saturated hydraulic conductivity ( K _s). We tested the individual effects of these factors on aggregate stability and related hydraulic properties, and studied the influence of clay mineralogy also. Samples from the surface (0–10 cm) of three contrasting soils in Trinidad were used. The soils were treated with three levels of Ca²⁺ and three levels of organic matter in a 3 × 3 × 3 factorial design and incubated for 14 days. Both aggregate stability and saturated hydraulic conductivity were influenced by all factor combinations. Interactions between soil type and Ca²⁺ revealed the importance of polyvalent cations in aggregate stability of soils with low activity minerals. The influence of organic matter varied with quantity; the more there was, the more stable the soil became, particularly in the soil containing little clay. Clay dispersion and slaking of expanding minerals occurred even with large additions of Ca²⁺ and organic matter, emphasizing the overall influence of mineralogy in determining the response of soils to stability treatments.     

耐盐碱细菌与有机物料对盐碱土团聚体形成的影响

从滨海盐碱土中分离筛选到分解秸秆、产胞外聚合物的耐盐碱细菌,通过土柱和盆栽试验研究其与有机物料相互作用对盐碱土团聚体形成以及植物生长的影响.结果表明,盐碱土中接种既分解秸秆又产胞外聚合物的耐盐碱细菌(菌株 M6),配施未腐熟秸秆,直接在盐碱土中腐熟分解,团聚体形成效果最好,大团聚体含量增加 60% 以上;施加玉米秸秆与施腐熟有机肥相比,前者更有利于盐碱土大团聚体的形成;盐碱土中接种既分解秸秆又产胞外聚合物细菌对团聚体形成的促进作用优于单功能分解秸秆细菌(菌株 J2)或者分泌胞外聚合物细菌(菌株 DF-2);菌株 M6 对盐碱环境下玉米的出苗、生长存活及干物质的积累有促进作用.     

Total, particulate organic matter and structural stability of a Calcixeroll soil under different wheat rotations and tillage systems in a semiarid area of Morocco

Wheat production in Morocco is constrained by both scarce climate and degraded soil quality. There is an urgent need to revert production decline while restoring country’s soils. Among conservation tillage systems known for their improvement in yield, no-till technology was found to influence soil quality as well. Soil quality indices are also affected by wheat rotations at medium and long-terms. This paper discusses changes in selected properties of a Calcixeroll soil, including total and particulate soil organic matter (SOM), pH, total N and aggregation, subjected, for 11 consecutive years, to various conservation and conventional agricultural systems. Tillage systems included no-tillage (NT) and conventional tillage (CT). Crop rotations were continuous wheat, fallow–wheat, fallow–wheat–corn, fallow–wheat–forage and fallow–wheat–lentils. Higher aggregation, carbon sequestration, pH decline and particulate organic matter (POM) buildup are major changes associated with shift from conventional- to NT system. Better stability of aggregates was demonstrated by a significantly greater mean weight diameter under NT (3.8 mm) than CT system (3.2 mm) at the soil surface. There was 13.6% SOC increase in (0–200 mm) over the 11-year period under NT, while CT did not affect much this soil quality indicator. Another valuable funding is the stratification of SOC and total nitrogen in NT surface horizon (0–25 mm) without their depletion at deeper horizon compared to tillage treatments. Fallow–wheat system resulted in reduction of SOC compared to WW, but 3-year wheat rotation tended to improve overall soil quality. Benefits from crop rotation in terms of organic carbon varied between 2.6 and 11.7%, with fallow–wheat–forage exhibiting the maximum. Combined use of NT and 3-year fallow rotation helped to improve soil quality in this experiment.     

基于热分析技术的土壤有机质含量和稳定性分析

土壤有机质(soil organic matter,SOM)含量及其稳定性是评价土壤质量的重要指标。传统的化学氧化技术测定SOM时可能氧化不完全,费时费力,容易污染实验室环境;干烧法(例如,元素分析法)分析成本高,而且化学氧化法和干烧法都难以提供SOM稳定性的信息。该文探讨应用热分析技术测定SOM含量及热稳定性的可行性。土壤样品采自位于湖南省宁乡县的稻田施肥长期定位试验,采用湿筛法将耕层土壤样品分为2、0.25~2、0.05~0.25以及≤0.05 mm 4个粒级团聚体,利用热重分析(thermogravimetry,TG)和差示扫描量热分析(differential scanning calorimetry,DSC)技术测定土体及团聚体中SOM含量和稳定性。结果表明:1)土壤中存在2类热稳定性不同的SOM:一类为热易分解型,分解温度为200~350℃;另一类为热稳定性型,分解温度为350~550℃;2)热分析技术测定的土体和团聚体中SOM质量分数范围为4%~8%,而元素分析仪得到的SOM质量分数范围约为3%~6%,热分析法结果比元素分析法的结果平均高估2.10百分点,但二者存在显著线性相关(r=0.88,P=0)。因此,可以利用该系数(2.10%)将热分析技术测定的SOM含量校正为元素分析法测定的结果;3)SOM的热稳定性可以用热易分解SOM占总SOM的比例(Exo1/Exot)和SOM分解一半时的温度(TG-T50)来表征,Exo1/Exot和TGT50呈良好的负相关(r=-0.95,P=0),但Exo1/Exot对SOM的热稳定性更加敏感,因此用Exo1/Exot表征SOM的热稳定性可能更为合理;4)Exo1/Exot与碳水化合物、烷烃类、芳香族的傅立叶转换红外线光谱吸光度以及土壤基础呼吸和微生物代谢熵q CO2呈显著正相关,说明SOM的热稳定性与化学稳定性、生物稳定性存在良好的一致性;5)长期有机肥和化肥配施显著提高了土体及各粒级团聚体的SOM含量,秸秆还田也具有较好的效果,但单施化肥无明显效果;0.25~2 mm粒级的团聚体是贮藏SOM的优势粒级,其次为2和≤0.05 mm的团聚体;6)对于同一粒级团聚体或土体,与单施化肥和不施肥相比,有机肥配施化肥和秸秆还田下的SOM热稳定性有降低趋势;尽管SOM热稳定性在各粒级团聚体和土体中存在一定差异,但是各施肥处理中没有一致规律。利用热分析技术测定SOM含量和热稳定性具有可行性,可以应用于研究农田管理措施对SOM含量和稳定性的影响和综合评价土壤质量。     

生物质炭与有机物料配施的土壤培肥效果及对玉米生长的影响

生物质炭作为一种多功能的土壤培肥材料被广泛应用,但其与传统有机物料的对比及配施研究还比较少。通过盆栽试验,研究了生物质炭与秸秆、发酵鸡粪单施及配施对壤质潮土和砂土养分含量、酶活性及玉米生长的影响,并采用主成分分析方法对3种有机物料的培肥效果进行综合评价。试验设6个处理,分别为不添加有机物料(CK)、添加生物质炭(BC)、小麦秸秆(WS)、发酵鸡粪(CM)、秸秆和生物质炭(WS+BC)、鸡粪和生物质炭(CM+BC)。研究结果表明,各处理均增加了砂土玉米生物量和株高,3种有机物料的提升幅度排序为:鸡粪生物质炭秸秆,鸡粪还可增加壤质潮土玉米生物量和株高。添加生物质炭和有机物料还可提高土壤有机质含量,其中生物质炭的提升幅度最大。此外,3种有机物料对土壤养分和酶活性的影响各异,单施鸡粪分别增加壤质潮土和砂土的碱解氮22.08%和26.67%,速效磷91.92%和53.65%,脲酶活性40.54%和36.94%;单施生物质炭分别增加壤质潮土和砂土速效磷83.52%和89.91%,速效钾79.38%和127.02%,过氧化氢酶活性3.41%和11.22%,却降低了土壤碱解氮含量,且与鸡粪配施后会抑制鸡粪中氮的有效性;单施秸秆分别增加壤质潮土和砂土速效钾49.48%和63.02%,β-葡糖苷酶活性51.86%和59.09%;生物质炭与鸡粪或秸秆配施可以更均衡地提升土壤肥力。通过主成分分析和相关分析发现,玉米生物量和株高与土壤氮、磷供应正变化的第2主成分(PC2)得分呈极显著正相关关系。因此,3种有机物料中,鸡粪对土壤氮、磷含量及相关酶活性影响最大;秸秆对土壤钾以及纤维素分解相关酶影响较大,而生物质炭对土壤肥力的提升作用更均衡,且土壤肥力综合得分最高。秸秆或鸡粪配施生物质炭可以更全面地提高土壤肥力。     

铵、钾同时存在时, 土壤对铵的优先吸附

The water stability of aggregates in various size classes separated from 18 samples of red soils under different managements, and the mechanisms responsible for the formation of water-stable soil aggregates were studied. The results showed that the water stability of soil aggregates declined with increasing size, especially for the low organic matter soils. Organic matter plays a key role in the formation of water-stable soil aggregates. The larger the soil aggregate size, the greater the impact of organic matter on the water stability of soil aggregates. Removal of organic matter markedly disintegrated the large water-stable aggregates (> 2.0 mm) and increased the small ones (< 0.25-0.5mm) to some extent, whereas removal of free iron(aluminium) oxides considerably destroyed aggregates of all sizes, especially the < 0.25-0.5 mm classes. The contents of organic matter in water-stable aggregates increased with aggregate sizes. It is concluded from this study that small water-stable aggregates (< 0.25-0.5 mm) were chiefly cemented by Fe and Al oxides whilst the large ones (> 2.0 mm) were mainly glued up by organic matter. Both free oxides and organic matter contribute to the formation and water stability of aggregates in red soils.     

Effect of cover crop management on soil organic matter

Characterization of soil organic matter (SOM) is important for determining the overall quality of soils, and cover crop system may change SOM characteristics. The purpose of this study was to examine the effect of cover crops on the chemical and structural composition of SOM. We isolated humic substances (HS) from soils with the following cover crop treatments: (a) vetch (Vicia Villosa Roth.)/rye (Sesale cereale L.), (b) rye alone, and (c) check (no cover crops) that were treated with various nitrogen (N) fertilizer rates. CPMAS-TOSS (cross-polarization magic-angle-spinning and total sideband suppression) ¹³C NMR results indicated that humic acids (HA) from soils under rye only were more aromatic and less aliphatic in character than the other two cover crop systems without fertilizer N treatment. Based on the DRIFT (diffuse reflectance Fourier transform infrared) spectra peak O/R ratios, the intensities of oxygen-containing functional groups to aliphatic and aromatic (referred to as recalcitrant) groups, the highest ratio was found in the HA from the vetch/rye system with fertilizer N. The lowest ratio occurred at the vetch/rye system without fertilizer N treatment. The O/R ratio of fulvic acids (FA) can be ranked as: vetch/rye without fertilizer>vetch/rye with fertilizer>no cover crop without fertilizer>rye alone (with or without fertilizer) soils. Both organic carbon (OC) and light fraction (LF) contents were higher in soils under cover crop treatments with and without fertilizer N than soils with no cover crop. These chemical and spectroscopic data show that cover crops had a profound influence on the SOM and LF characteristics.     

Effect of soil organic matter, electrical conductivity and sodium adsorption ratio on tensile strength of aggregates

The properties of soils affected by salinity and processes involving degradation of soil structure have been partly recognized. However, the effects of saline and sodic conditions on mechanical and physical properties of soils have been studied to a lesser extent. In this research, the effects of electrical conductivity (EC) and sodium adsorption ratio (SAR) on soils possessing various amounts of organic matter were assessed under laboratory conditions. The soils contained a uniform clay type, predominantly Illite. The major difference of the soils was their amount of organic matter content. The treatments consisted of solutions with definite EC and SAR (two levels of EC: 0.5 and 4 dS/m and three levels of SAR: 0, 5 and 15). The amount of tensile strength was dependent on organic matter, EC, and SAR in a way that with the increase of SAR, the tensile strength decreased. In similar SAR, treatments with higher EC exhibited greater tensile strength. Also, the soils with higher organic matter showed greater tensile strength. The analysis of variance showed the significant difference (at 1%) between the mean of parameters analyzed (soil type, sampling depth, EC, and SAR). The order of averages of tensile strength were: permanent pasture (Agropyron elengatum)Festuca arusdinaceae)相似文献   

Evaluating biodegradability of soil organic matter by its thermal stability and chemical composition

The stability of soil organic matter (SOM) as it relates to resistance to microbial degradation has important implications for nutrient cycling, emission of greenhouse gases, and C sequestration. Hence, there is interest in developing new ways to quantify and characterise the labile and stable forms of SOM. Our objective in this study was to evaluate SOM under widely contrasting management regimes to determine whether the variation in chemical composition and resistance to pyrolysis observed for various constituent C fractions could be related to their resistance to decomposition. Samples from the same soil under permanent pasture, an arable cropping rotation, and chemical fallow were physically fractionated (sand: 2000-50 μm; silt: 50-5 μm, and clay: <5 μm). Biodegradability of the SOM in size fractions and whole soils was assessed in a laboratory mineralization study. Thermal stability was determined by analytical pyrolysis using a Rock-Eval pyrolyser, and chemical composition was characterized by X-ray absorption near-edge structure (XANES) spectroscopy at the C and N K-edges. Relative to the pasture soil, SOM in the arable and fallow soils declined by 30% and 40%, respectively. The mineralization bioassay showed that SOM in whole soil and soil fractions under fallow was less susceptible to biodegradation than that in other management practices. The SOM in the sand fraction was significantly more biodegradable than that in the silt or clay fractions. Analysis by XANES showed a proportional increase in carboxylates and a reduction in amides (protein) and aromatics in the fallow whole soil compared to the pasture and arable soils. Moreover, protein depletion was greatest in the sand fraction of the fallow soil. Sand fractions in fallow and arable soils were, however, relatively enriched in plant-derived phenols, aromatics, and carboxylates compared to the sand fraction of pasture soils. Analytical pyrolysis showed distinct differences in the thermal stability of SOM among the whole soil and their size fractions; it also showed that the loss of SOM generally involved preferential degradation of H-rich compounds. The temperature at which half of the C was pyrolyzed was strongly correlated with mineralizable C, providing good evidence for a link between the biological and thermal stability of SOM.     

黑垆土长期轮作培肥土壤有机质氧化稳定性的研究

以黄土旱塬长期定位试验为研究材料,分析了不同轮作与施肥对土壤有机质的含量及氧化稳定性的影响。在轮作系统引入豆科作物后,有机碳和易氧化有机碳含量增加,且豆科作物茬口的氧化稳定性低于小麦茬口,利于养分的释放和肥力的持续供给。培肥对氧化稳定性的影响表现在:长期不施肥或单施化肥氧化稳定性升高,促进了土壤有机质的老化。有机肥或有机无机配施能明显提高易氧化有机碳的含量,降低有机质的氧化稳定性,提高土壤肥力水平。苜蓿连作土壤剖面Kos的变化显示:随土层深度的增加,氧化稳定性也逐渐增加。     

Invertebrate control of soil organic matter stability

 The control of soil organic matter (SOM) stability by soil invertebrates is evaluated in terms of their impact on the inherent recalcitrance, accessibility to microorganisms, and interaction with stabilizing substances of organic compounds. Present knowledge on internal (ingestion and associated transformations) and external (defecation, constructions) control mechanisms of soil invertebrates is also reviewed. Soil animals contribute to the stabilization and destabilization of SOM by simultaneously affecting chemical, physical, and microbial processes over several orders of magnitude. A very important aspect of this is that invertebrates at higher trophic levels create feedback mechanisms that modify the spatio-temporal framework in which the micro-food web affects SOM stability. Quantification of non-trophic and indirect effects is thus essential in order to understand the long-term effects of soil biota on SOM turnover. It is hypothesized that the activities of invertebrates which lead to an increase in SOM stability partly evolved as an adaptation to the need for increasing the suitability of their soil habitat. Several gaps in knowledge are identified: food selection and associated changes in C pools, differential effects on SOM turnover, specific associations with microorganisms, effects on dissolution and desorption reactions, humus-forming and humus-degrading processes in gut and faeces, and the modification of invertebrate effects by environmental variables. Future studies must not be confined merely to a mechanistic analysis of invertebrate control of SOM stability, but also pay considerable attention to the functional and evolutionary aspects of animal diversity in soil. This alone will allow an integration of biological expertise in order to develop new strategies of soil management which can be applied under a variety of environmental conditions. Received: 6 April 1999     

用Wien效应研究土壤有机质对阳离子与黄棕壤型水稻土黏粒相互作用的影响

选择富含有机质的黄棕壤型水稻土,提取小于2μm的黏粒,将其中1/2黏粒去除有机质,分别制成为不同阳离子(Na+、K+、NH4+、Ca2+、Cd2+和La3+)饱和的土样,用Wien效应法研究土壤有机质对阳离子与土壤黏粒相互作用的影响。研究结果表明:原土悬液的起始电导率大于去有机质土者;除含Na+悬液外,去有机质土悬液的电导率随场强而增加的速率在50～100 kV cm-1以上,明显大于原土。有机质会使Na+以外的阳离子的平均结合自由能增大,Ca2+的结合能增加最大(增量为0.57 kJ mol-1),而Cd2+的结合能增加最小(增量为0.03 kJ mol-1)。对于供试土壤悬液,不同阳离子的结合能顺序均为Na+相似文献   

Use of organic carbon and loss-on-ignition to estimate soil organic matter in different soil types and horizons

Summary Loss-on-ignition (LOI) and the organic C content have been used to estimate soil organic matter. Organic matter is often estimated from organic C by applying a factor of 1.724. Several authors have examined the relationship between LOI, used as an estimate of organic matter, and C by simple linear regressions. In the present study, this approach was examined in relation to two sets of data. LOI overestimates organic matter in soils with significant proportions of clay minerals because of bound water, and correcting for bound water gives some LOI: C ratios of less than 1. It is concluded that differences in the nature of the organic matter in different soils and horizons make the simple regression approach unsuitable. More attention needs to be paid to studies of the nature of the organic matter.     

Effect of fractionation on location of enzyme activities in soil structural units

Summary Two different soils were fractionated with three granulometric procedures. Enzyme activity measurements were carried out in four fractions of real (undisturbed), stable (water-dispersed) and structural (water-dispersed and physically disrupted) soil units.A predominance of catalase (67.3%), dehydrogenase (57.6%) and urease (65.3%) activities was observed in soil structural microunits with diameters of less than 50 m. Highest protease activity was found in fractions with a diameter of less than 50 m (66.3%) and in fractions with a diameter ranging from 200 to 2000 m (18.5%) which contain organic matter of a higher and lower grade of humification, respectively.All fractionation procedures result in a loss of total enzyme activities, which was more clear in the physically disrupted soil than in the sieved soil (e.g. 38.4% vs. 5.9% loss of urease activity).     

侵蚀程度对不同粒径团聚体中养分含量和红壤有机质稳定性的影响

以三种侵蚀程度的红壤(轻度、中度、严重)为供试材料,研究其>0.25 mm水稳性团聚体中的养分(全氮、全磷、全钾、有机质)和不同形态有机碳(易氧化态和难氧化态)的含量状况和分布特点。结果表明:随着红壤由轻度、中度到严重侵蚀的变化,>0.25 mm水稳性团聚体中有机质、全氮和全磷含量逐渐降低;>0.25 mm水稳性团聚体中的养分对土壤养分的贡献率为[>4 mm]>[0.5～1 mm]>[1～2 mm]>[2～4 mm]>[0.25～0.5 mm];侵蚀红壤的全氮、全磷和有机质均与>0.25 mm水稳性团聚体含量显著正相关。土壤有机碳、易氧化碳和难氧化碳的含量随着红壤侵蚀程度的增强逐渐降低,并且均与>0.25 mm水稳性团聚体、有机质、全氮、全磷呈极显著正相关。有机质氧化稳定性系数与不同粒径水稳性团聚体、土壤有机质、全氮和全磷均呈负相关。     

添加无定形铝氧化物对雷竹林土壤有机质矿化的影响

土壤中无定形铝氧化物对有机质的存在有很大的影响,由于雷竹特殊的经营方式导致土壤中有机质快速积累,为了解无定形铝氧化物对土壤中快速积累的有机质分解产生的影响,本文通过往不同种植年限的雷竹林土壤中增加不同量的无定形铝氧化物(0、2、10、20、40 g/kg)以及室内密闭培养法测定CO2的释放量来反映有机质的分解状况,以便了解无定形铝氧化物对快速增加的雷竹林土壤有机质分解的影响,了解集约经营下的雷竹林土壤有机质的变化趋势及稳定性.结果表明,无定形铝氧化物的加入可显著抑制土壤有机质的分解,当无定形铝氧化物的加入量为40 g/kg时,对0年(水稻)、1年、5年、15年雷竹林土壤有机质分解的抑制率分别为56.97%、60.75%、58.87%、44.25%;0年(水稻)土壤加入无定形铝氧化物0、2、10、20、40 g/kg,对有机质分解的抑制效率分别为7.49%、38.04%、50.79%、56.98%.无定形铝氧化物对有机质分解的抑制效率随其加入量的增加而提高,但随土壤有机质含量的增加而下降.