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改良剂对旱地红壤微生物量碳、氮及可溶性有机碳、氮的影响 总被引：6，自引：2，他引：4
基于室内模拟培养试验,研究改良剂(生物质炭、过氧化钙)对旱地红壤微生物量碳、氮及可溶性有机碳、氮的影响。试验设置4个处理,即CK、Ca(过氧化钙,1.72g/kg)、C(生物质炭,21.46g/kg)、C+Ca。结果表明:各处理土壤微生物量碳、氮以及可溶性有机碳具有相同的变化趋势,即前期(3d内)都增加较快,在第3天达到最大值,随试验进行有所下降,配施效果优于单施。各处理可溶性有机氮在21d内缓慢增加;第21天时,C+Ca、Ca、C相比CK分别显著增加了62.1%,55.5%,40.9%;35d以后,配施(C+Ca)与单施过氧化钙(Ca)的效果显著优于单施生物质炭(C)和对照(CK)。120d培养期内,配施(C+Ca)处理能够明显提高微生物量碳、氮以及可溶性有机碳、氮的平均含量;微生物量碳的平均含量大小顺序为C+CaCCKCa,微生物量氮的平均含量C+Ca处理显著高于其他处理;可溶性有机碳的平均含量大小顺序为C+CaCaCCK,可溶性有机氮的平均含量C+Ca、Ca处理显著高于CK、C处理。微生物量碳、氮以及可溶性有机碳之间互为极显著正相关(P0.01),而微生物量碳与可溶性有机氮之间呈极显著负相关。因此,生物质炭和过氧化钙能有效提高旱地红壤微生物量碳、氮及可溶性有机碳、氮,且生物质炭与过氧化钙配合施用更有助于土壤改良。 相似文献
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Tianyun Wu Jeff J. Schoenau Fengmin Li Peiyuan Qian Sukhdev S. Malhi Yuanchun Shi 《Biology and Fertility of Soils》2006,42(4):338-344
The effects of several dominant tillage and rotation systems on soil organic C content of different particle-size fractions
were studied in Chernozemic soils from southwestern and east-central Saskatchewan, Canada. In an Orthic Brown Chernozem in
southwestern Saskatchewan, 7 years of no-till cereal–fallow, imposed on a long-term tillage fallow–wheat rotation soil, resulted
in 0.1 Mg C ha−1 more organic C mass in the sand + organic matter (OM) fraction of the 0- to 5-cm layer, whereas organic C associated with
coarse silt (CS), fine silt (FS), coarse clay, and fine clay of 0- to 5- and 5- to 10-cm layers was less than that of the
comparable tilled cereal–fallow system. Conversion of tilled fallow–wheat rotation soil to continuous cropping had a slight
effect, whereas the organic C mass in all the size fractions was significantly increased in both 0- to 5- and 5- to 10-cm
layers after alfalfa was introduced on tilled fallow–wheat as perennial forage for 10 years. In an Orthic Black Chernozem
in east-central Saskatchewan that was cultivated and tilled using a cereal–fallow rotation for 62 years, organic C mass decreased
in sand + OM, CS, and FS of 0- to 10-cm depth. Conversion of the tilled cereal–fallow cropland soil back to seeded grassland
resulted in significantly more soil organic C in sand + OM fraction after 12 years of grass seed-down. The sand + OM fraction
appears to be the size fraction pool initially most sensitive to adoption of management practices that are liable to sequester
carbon in the soil. 相似文献
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The activities of carbon‐cycle enzymes were measured in soil and aggregates to understand compost and inorganic fertilizer amendment effects on soil organic carbon accumulation in an intensively cultivated upland field. Soil samples were collected from a long‐term field experiment with seven treatments: compost, half‐compost N plus half‐fertilizer N, fertilizer NPK, fertilizer NP, fertilizer NK, fertilizer PK and no fertilizer control. The 18‐yr continuous application of compost increased organic C content in soil and three aggregate sizes by 72–124 and 78–234%, respectively, compared with the control. Fertilization also significantly increased organic C contents in soil, macroaggregates and the silt + clay fraction, but not in microaggregates. Compost application significantly reduced the specific activities of polyphenol oxidase (activity per unit organic C) in soil and three aggregate sizes compared with control, whereas fertilization had a much weaker effect. Compost amendment also significantly lowered the specific activities of invertase in macroaggregates and the silt + clay fraction, and this effect was more pronounced than the addition of fertilizer NPK. In contrast, inorganic fertilizer and compost application significantly increased the specific activities of cellobiohydrolase in soil, macroaggregates and microaggregates (but not in the silt + clay fraction), and xylosidase in microaggregates. The application of fertilizer NPK had a more pronounced effect than compost. We considered that the increase in organic C in compost‐amended soil was therefore probably associated with the accumulation of lignocellulose and sucrose in macroaggregates, lignocellulose and hemicellulose in microaggregates and lignin (its derivative) and nonstructural carbohydrates in the silt + clay fraction. However, the application of fertilizer NPK enhanced organic C probably due to an increase in the content of lignin (its derivative) and sucrose in macroaggregates and the silt + clay fraction. Therefore, the application of compost with high lignocellulose should be effective to increase soil organic C in the North China Plain. 相似文献
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Sergio A. BELMONTE Luisella CELI Ruby J. STAHEL Eleonora BONIFACIO Vittorino NOVELLO Ermanno ZANINI Kerri L. STEENWERTH 《土壤圈》2018,28(2):288-298
Vineyard management practices to enhance soil conservation principally focus on increasing carbon (C) input, whereas mitigating impacts of disturbance through reduced tillage has been rarely considered. Furthermore, information is lacking on the effects of soil management practices adopted in the under-vine zone on soil conservation. In this work, we evaluated the long-term effects (22 years) of alley with a sown cover crop and no-tillage (S + NT), alley with a sown cover crop and tillage (S + T), and under-vine zone with no vegetation and tillage (UV) on soil organic matter (SOM), microbial activity, aggregate stability, and their mutual interactions in a California vineyard in USA. Vegetation biomass, microbial biomass and activity, organic C and nitrogen (N) pools, and SOM size fractionation and aggregate stability were analysed. Soil characteristics only partially reflected the differences in vegetation biomass input. Organic C and N pools and microbial biomass/activity in S + NT were higher than those in S + T, while the values in UV were intermediate between the other two treatments. Furthermore, S + NT also exhibited higher particulate organic matter C in soil. No differences were found in POM C between S + T and UV, but the POM fraction in S + T was characterized by fresher material. Aggregate stability was decreased in the order: S + NT > UV > S + T. Tillage, even if shallow and performed infrequently, had a negative effect on organic C and N pools and aggregate stability. Consequently, the combination of a sown cover crop and reduced tillage still limited SOM accumulation and reduced aggregate stability in the surface soil layer of vineyards, suggesting relatively lower resistance of soils to erosion compared to no-till systems. 相似文献
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Dinesh Kumar Benbi Amardeep Singh Toor Gayatri Verma 《Communications in Soil Science and Plant Analysis》2016,47(15):1828-1844
The study was conducted to investigate the aggregate stability and distribution of organic carbon (C) in different-sized aggregates and mineral fractions in a loamy soil under rice-wheat system with continuous application of fertilizer nitrogen, phosphorus and potassium (NPK), farmyard manure (FYM), N+FYM and NPK+FYM, compared with unfertilized control. Macro-aggregates comprised 37.1–49.3% of the total water-stable aggregates (WSAs), compared with 23.3–30.3% as micro-aggregates. Application of inorganic fertilizers and FYM significantly increased the proportion of macro-aggregates, which were linearly related to total organic C (TOC). Organic C concentration in coarse macro-aggregates (CMacA) was higher than the micro-aggregates (CMicA). Application of FYM significantly increased the concentration of organic C in different-sized aggregates and mineral fraction, compared with the unfertilized control. Averaged across treatments, mineral-associated C comprised 26% of TOC. Macro-aggregates, on an average, constituted 66–68% of C preservation capacity of WSA. The amount of TOC sequestered was higher when NPK+FYM was applied together. 相似文献
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《Applied soil ecology》2001,16(3):229-241
Changes in the proportions of water-stable soil aggregates, organic C, total N and soil microbial biomass C and N, due to tillage reduction (conventional, minimum and zero tillage) and crop residue manipulation (retained or removed) conditions were studied in a tropical rice–barley dryland agroecosystem. The values of soil organic C and total N were the highest (11.1 and 1.33 g kg−1 soil, respectively) in the minimum tillage and residue retained (MT+R) treatment and the lowest (7.8 and 0.87 g kg−1, respectively) in conventional tillage and residue removed (CT−R) treatment. Tillage reduction from conventional to minimum and zero conditions along with residue retention (MT+R,ZT+R) increased the proportion of macroaggregates in soil (21–42% over control). The greatest increase was recorded in MT+R treatment and the smallest increase in conventional tillage and residue retained (CT+R) treatment. The lowest values of organic C and total N (7.0–8.9 and 0.82–0.88 g kg−1 soil, respectively) in macro- and microaggregates were recorded in CT−R treatment. However, the highest values of organic C and total N (8.6–12.6 and 1.22–1.36 g kg−1, respectively) were recorded in MT+R treatment. The per cent increase in the amount of organic C in macroaggregates was greater than in microaggregates. In all treatments, macroaggregates showed wider C/N ratio than in microaggregates. Soil microbial biomass C and N ranged from 235 to 427 and 23.9 to 49.7 mg kg−1 in CT−R and MT+R treatments, respectively. Soil organic C, total N, and microbial biomass C and N were strongly correlated with soil macroaggregates. Residue retention in combination with tillage reduction (MT+R) resulted in the greatest increase in microbial biomass C and N (82–104% over control). These variables showed better correlations with macroaggregates than other soil parameters. Thus, it is suggested that the organic matter addition due to residue retention along with tillage reduction accelerates the formation of macroaggregates through an increase in the microbial biomass content in soil. 相似文献
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The main objectives were to study the effects of pH on the retention and release of organic matter in acid soil, and to determine the main differences in results obtained from batch experiments and experiments in columns. We took soil material from the B horizons of a Podzol at Skånes Värsjö (southern Sweden). In batch experiments, soil was equilibrated with solutions varying in pH and concentration of dissolved organic C. In Bh samples, the release of dissolved C gradually increased with increase in pH. In the Bs1 material there was a minimum at pH 4.1, and in the Bs2 soil the minimum occurred at pH 4.6. The ability to retain added dissolved C increased in the order Bh < Bs1 < Bs2. The column experiment was run for 160 days under unsaturated flow conditions. Columns were packed with Bh, Bh + Bs1 or Bh + Bs1 + Bs2 samples to calculate mass balances for each horizon. Solutions either without any dissolved organic C or ones containing 49 mg C dm?3 with pH of 4.0 or 3.6 were used to leach columns. The pH of input solutions only little affected the concentration of dissolved C in the effluent. Relative proportions of hydrophobic substances decreased with increasing column length and decreasing pH. For input solutions containing dissolved C, near steady state was achieved for both the Bs1 and Bs2 horizons with approximately 25% dissolved organic matter retention. Thus, no maximum sorption capacity for dissolved C could be defined for these horizons. This behaviour could not have been predicted by batch data, showing that column experiments provide useful additional information on interactions between organic compounds and solid soil material. 相似文献
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不同稳定性有机物料对砂姜黑土理化性质及玉米产量的影响 总被引：8，自引：2，他引：8
针对黄淮海平原广泛分布的砂姜黑土结构性差、有机质含量偏低的特征,通过中国科学院封丘农田生态系统国家试验站2年砂姜黑土不同外源有机物料施用处理盆栽试验[共设8个处理,分别为空白(CK)、施秸秆(S)、施有机肥(M)、施1/2秸秆+1/2有机肥(SM)、施生物炭(C)、施1/2生物炭+1/2秸秆(CS)、施1/2生物炭+1/2有机肥(CM)和施1/3生物炭+1/3有机肥+1/3秸秆(CSM)],研究了等C、N输入下不同稳定性有机物料(生物炭、秸秆、有机肥)对砂姜黑土理化性质及玉米产量的影响。结果表明,与CK处理相比,施用外源有机物料能显著降低土壤容重19.60%~32.23%,增加饱和含水量7.91%~28.99%、田间持水量10.47%~30.76%,提高耕层土壤总孔隙度10.36%~28.21%,提升全量有机质11.00%~37.00%;并对活性有机质组分(低活性有机质、中活性有机质、高活性有机质)产生显著影响,其中高活性有机质增加幅度高达39.22%~83.83%。从有机物料的配比效果来看,CSM处理土壤容重最低,为1.28 g?cm?1,C、S处理土壤容重分别为1.30 g?cm?1、1.36 g?cm?1。CSM处理土壤总孔隙度最大,为58.53%;S、CS、SM处理次之,分别为55.62%、56.90%、54.38%;C、M处理最小,分别为53.18%、50.38%。CS、CM、CSM处理土壤总有机质含量较高,分别为30.76 g?kg?1、32.99 g?kg?1、31.45 g?kg?1;C、S处理相对较低,分别为25.36 g?kg?1、26.16 g?kg?1。CS、SM、CSM处理玉米产量最高,分别为463.67 g?盆?1、376.31 g?盆?1、471.77 g?盆?1,且差异性显著。可见不同稳定性有机物料施入能够改善土壤理化性质,提高玉米产量,生物炭配合秸秆、有机肥还田处理改良土壤及增产效果最佳。 相似文献
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有机物料输入稻田提高土壤微生物碳氮及可溶性有机碳氮 总被引：27，自引：6，他引：27
土壤微生物量碳、氮和可溶性有机碳、氮是土壤碳、氮库中最活跃的组分,是反应土壤被干扰程度的重要灵敏性指标,通过设置相同有机碳施用量下不同有机物料处理的田间试验,研究了有机物料添加下土壤微生物量碳（soil microbial biomass carbon,MBC）、氮（soil microbial biomass nitrogen,MBN）和可溶性有机碳（dissolved organic carbon,DOC）、氮（dissolved organic nitrogen,DON）的变化特征及相互关系。结果表明化肥和生物碳、玉米秸秆、鲜牛粪或松针配施下土壤微生物量碳、氮和可溶性有机碳、氮显著大于不施肥处理（no fertilization,CK）和单施化肥处理,分别比不施肥处理和单施化肥平均高23.52%和12.66%（MBC）、42.68%和24.02%（MBN）、14.70%和9.99%（DOC）、22.32%和21.79%（DON）。化肥和有机物料配施处理中,化肥+鲜牛粪处理的微生物量碳、氮和可溶性有机碳、氮最高,比CK高26.20%（MBC）、49.54%（MBN）、19.29%（DOC）和32.81%（DON）,其次是化肥+生物碳或化肥+玉米秸秆处理,而化肥+松针处理最低。土壤可溶性有机碳质量分数（308.87 mg/kg）小于微生物量碳（474.71 mg/kg）,而可溶性有机氮质量分数（53.07 mg/kg）要大于微生物量氮（34.79 mg/kg）。与不施肥处理相比,化肥和有机物料配施显著降低MBC/MBN和DOC/DON,降低率分别为24.57%和7.71%。MBC和DOC、MBN和DON随着土壤有机碳（soil organic carbon,SOC）、全氮（total nitrogen,TN）的增加呈显著线性增加。MBC、MBN、DOC、DON、DOC+MBC和DON+MBN之间呈极显著正相关（P<0.01）。从相关程度看,DOC+MBC和DON+MBN较MBC、DOC、MBN、DON更能反映土壤中活性有机碳和氮库的变化,成为评价土壤肥力及质量的更有效指标。结果可为提高洱海流域农田土壤肥力,增强土壤固氮效果,减少土壤中氮素流失,保护洱海水质安全提供科学依据。 相似文献
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长期施肥潮土在玉米季施肥初期的有机碳矿化过程研究 总被引：9，自引：2，他引：7
以黄淮海平原长期定位试验地2007年玉米播种期土壤为研究对象,通过室内37天的培养实验并选择4个应用比较广泛的方程对土壤有机碳矿化过程进行拟合,其目的主要是为了比较研究长期不同施肥土壤在玉米季施肥初期有机碳矿化过程及主要矿化参数的差异,并评估矿化参数和主要土壤性质之间的相关关系.结果表明,37天培养期内各施肥处理土壤CO2-C累积释放量与土壤有机碳、全氮含量和微生物活度均呈显著正相关,大小依次为OM＞1/2OM+1/2NPK＞NPK＞NP＞PK＞CK＞NK,有机碳矿化过程均呈曲线形式,与Jones(1984)改进的一级动力学方程拟合效果最好.拟合所得土壤潜在可矿化有机碳量(C0)、易矿化有机碳量(C1)和初始潜在矿化速率(C0k)均表现出有机肥处理高于化肥处理,施肥处理高于不施肥处理(NK处理除外),与土壤有机碳、全氮和土壤微生物活度均呈显著正相关;有机碳矿化速率(k)和土壤潜在可矿化有机碳占土壤总有机碳的比例在处理间差异均不显著,除k与有机碳呈显著负相关外,其他与土壤性质均无显著相关性.因此,我们推测有机肥和化肥的平衡施用均能显著增强土壤有机碳的矿化作用,有利于土壤无机养分的释放,同时使部分有机碳在土壤中积累. 相似文献
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稻草覆盖对坡地红壤培肥及作物增产的效果 总被引：7，自引：1，他引：7
研究了坡地红壤连续5年采用稻草覆盖措施对土壤肥力和作物产量的影响。结果表明,“稻草+化肥氮磷”(“Straw+NP”)处理的土壤有机碳和全氮、磷分别比不施肥(CK)的提高42.9%和17.4%、44.2%,有机碳和全氮的增幅约是纯化肥(NPK)处理的2倍。与CK和NPK处理的相比,“Straw+NP”处理能明显提高微生物生物量碳、氮、磷和溶解性有机碳、氮以及Olsen-P含量,差异达到显著(P<0.05)或极显著(P<0.01)水平。在等养分施用量的条件下,“Straw+NP”处理能显著提高油菜和甘薯的产量。因此,稻草易地覆盖是一种有效培肥坡地红壤和增加作物产量的途径。 相似文献
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D. Fangueiro A. López-Piñeiro J.M. Rato Nunes F. Cabral 《Soil Science and Plant Nutrition》2013,59(2):327-336
AbstractTwo-phase olive mill waste (TPOMW) and dairy cattle slurry (CS) are two organic materials with low economic value and limited potential for reutilization despite their high concentrations of nitrogen (N) and organic matter. A laboratory incubation for ca. 100 d was performed to assess the short-term N and carbon (C) dynamics in a soil amended with TPOMW, CS and a mixture of both materials in order to: (i) explore the potential benefits of mixing TPOMW with CS to promote mineral N immobilization and avoid nitrate leaching, and (ii) assess the potential for increased soil C stocks after TPOMW, CS or TPOMW+CS application. Our results clearly showed that the combined application of TPOMW+CS caused N immobilization; hence, it contributes to tying up the applied N, resulting in a decrease of critical N leaching, which is usually observed after CS application. No clear N mineralization was observed in the TPOMW+CS treatment during the incubation period.It appears that an application of 30 Mg ha?1 of TPOMW is enough to decrease net N mineralization from applied CS, as the C:N ratio of the mixture TPOMW+CS is 27. More than 40% of the TPOMW-derived C remained in the soil at the end of the experiment in treatments with single and combined application of TPOMW+CS, indicating that such materials have the potential to increase C stocks in soil. It can be concluded that a combined application of TPOMW+CS is of interest to maintain the CS-derived N in organic form during a longer time period and minimize risks of nitrate leaching, although further studies are necessary to define a better TPOMW:CS ratio which allows a proper plant N uptake. 相似文献
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不同质地小麦根际土壤有机碳、氮含量及特性研究 总被引：3，自引：0，他引：3
测定了两种不同质地土壤小麦根际土及非根际土中不同形态有机碳、氮的含量及特性。结果表明,粘壤土及砂质壤土两种不同质地土壤小麦根际土中有机碳、可溶性有机碳(WEOC),土壤全氮、可溶性有机氮(WEON)、游离氨基酸及硝态氮和铵态氮均显著高于非根际土;根际土及非根际土中WEON的含量均高于硝态氮及铵态氮含量,其在根-土界面氮素转化中的作用值得关注。不同质地土壤相比,粘壤土中各指标的含量均显著高于砂质壤土。根际土有机碳矿化累积量及矿化率均高于非根际土;培养期间粘壤土释放的CO2量明显低于沙质壤土,这可能与粘壤土粘粒含量高,对土壤有机碳的保护作用有关。 相似文献
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Summary The concentrations of organic C and total N in five different particle-size fractions were studied under different mineral and organic fertilizer regimens by examining soil samples from the 34-year-old soil-formation pot experiment Hu 3 in Rostock. The C and N concentrations were generally highest in the clay fraction and decreased in the order medium silt >fine silt >coarse silt and sand. For nearly all years and size fractions the following order was obtained for C and N concentrations under the various fertilizer regimens: Compost >farmyard manure >straw + mineral fertilizer >mineral fertilizer. The various particle-size fractions and fertilizer regimens differed in the development of soil organic matter levels. Consequently, characteristic redistributions were found in the proportions of C and N in the various particle-size fractions, particularly after organic fertilizer was no longer applied (years 20–34). This experimental phase was characterized by decreased organic C and increased total N concentrations, and increased proportions of C and N in the clay-size at the expense of the sand fractions. 相似文献