Lime Incorporation Research Articles

石灰与水泥改性花岗岩残积土耐久性的对比评价

花岗岩残积土粘聚力小，水稳定性差，遇水易崩解，应用时需进行土体改性。其中在土体中掺入水泥或石灰是最常用的化学改性方式。展开室内试验，分别将石灰及水泥掺入花岗岩残积土进行土体改性，从CBR强度、崩解特性和水稳性三个方面对比评价石灰与水泥改性花岗岩残积土耐久性。结果表明，在最佳掺加量下，水泥改性后的各项指标基本均优于石灰改性，水泥改性花岗岩残积土的耐久性更优。 Granite residual soil has little cohesive force and poor water stability. It is easy to disintegrate in water, and soil modification is needed in application. The incorporation of cement or lime in the soil is the most commonly used chemical modification. The lime and cement were mixed into granite residual soil for soil modification, and the durability of lime and cement modified granite residual soil was evaluated from CBR strength, disintegration characteristics and water stability. The results show that under the optimal dosage, the indexes of cement modification are better than lime modification, and the durability of cement-modified granite residual soil is better.

<b>Effect of liming on micronutrient availability to soybean grown in soil under different lengths of time under no tillage

The effect of liming on the availability of micronutrients to soybean cultivated during different numbers of years under no tillage (NT) was investigated. The treatments consisted of the number of years under NT (three, six, and nine years) and five rates of lime (0, 33, 67 and 100% of the amount calculated to raise soil base saturation to 70%) broadcast on soil surface plus the rate of 100% broadcast with incorporation in the 0-0.20 m layer of a clayey Red Oxisol. Soil and leaf samples were collected at two vegetative stages of the crop (vegetative V4 and blossoming R2). The soil was sampled at depths of 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. Surface liming had little effect on extractable soil micronutrient and nutrient concentrations in soybean leaves. In the area with three years under NT, all liming rates decreased the extractable soil Zn up to a depth of 0.20 m. Lime incorporation decreased the extractable soil Mn in the surface layer. There were no differences in the extractable soil micronutrients and nutrient concentrations in soybean leaves as a function of the number of years under NT. These data suggest that broadcasting lime at current rates on soils under NT does not necessarily lead to micronutrient deficiencies.

Liming in the conversion from degraded pastureland to a no-till cropping system in Southern Brazil

A significant area in Brazil is covered with degraded pasturelands, which could be more appropriately used under no-till system. These soils are highly acid and physically fragile, and then there is a need to identify a better liming strategy that will improve the establishment of no-till systems. We hypothesized that the surface application of lime would be more efficient to alleviate soil acidity on degraded pastureland soils. A 4-year field trial examined the effect of a lime application (4.8Mgha−1) that had either been incorporated (0–20cm) or surface-applied to an acid sandy loam Oxisol, originally under degraded pasture in Southern Brazil. Control treatments (no-lime) were applied with and without soil disturbance. A black oat (Avena strigosa Schreb) – soybean (Glycine max L. Merrill) cropping sequence was used for 4 years after no-till establishment. Soil chemical attributes, plant nutrient uptake, black oat dry biomass production and soybean grain yield were assessed. Soil acidity amelioration was achieved either by incorporating the lime or applying it onto the soil surface. Lime incorporation resulted in a faster neutralization reaction, whereas surface-applied lime provided longer lasting soil profile benefits. At 0–5cm layer, both tillage treatments, especially with lime application, provided lower soil organic carbon levels than no-till treatments, with or without lime application, until the second year. These differences in soil organic carbon levels were not observed at the end of evaluation, after 4 years, probably because the residual tillage effect disappeared. Over time, the soil organic carbon levels at 5–10cm layer were slightly increased or maintained close to the initial level, regardless of treatment. Overall, the plants responded to lime application, with an increase by 35% on soybean yield, regardless of the application method. Surface liming provided better economic returns than incorporated liming. Lime incorporation is not recommended in degraded lands due to the risks of SOC losses with soil disturbance and rapid pH increase. Despite of high soil acidity before no-till cultivation, the surface application of lime was the best alternative for alleviating soil acidity when establishing a no-till system on degraded pastureland.

Soil Chemical and Physical Properties on an Inceptisol after Liming (Surface and Incorporated) Associated with Gypsum Application

Inceptsoils have high aluminum contents, and amendments are required to ensure a satisfactory crop development. Liming is efficient in neutralizing Al3+, but when applied to the topsoil its action is restricted to the surface layers, and sometimes lime incorporation into the soil is recommendable. However, tillage may negatively alter physical soil properties. Thus, gypsum could be an alternative to increase Ca2+ levels and reduce Al saturation in deeper layers, without requiring tillage. An experiment was initiated in 2010, to assess chemical and physical soil properties. Soil samples were collected in February 2013. A random block design with sub-subplots and two replications was used. Lime was applied to the surface of the main plot (0, 8 and 16 Mg ha-1) and incorporated into the soil by plowing and light harrowing. Gypsum was applied to the subplot (0 and 6 Mg ha-1), and the sub-subplots corresponded to the sampled layers (thickness of 0.05 m, to a depth of 0.25 m). The following parameters were evaluated: pH in water, base saturation, Al saturation, Ca2+, Mg2+, soil organic matter, water retention, and least limiting water range (LLWR). Lime incorporated into the soil reduced Al3+ and increased pH and Ca2+ levels, especially in the deeper soil layers, although pH levels did not exceed 5.1 and base saturation was lower than 60 %, still inadequate for crops. The gypsum rate of 6 Mg ha-1 did not decrease Al saturation, but reduced Mg2+ levels in top soil layers. Soil water retention and LLWR were not affected by plowing and harrowing within a period of three years. Gypsum rates below 6 Mg ha-1 were not effective in reducing Al saturation and increasing Ca2+ levels. Incorporated lime is more effective in correcting the acidity of the soil profile and, after three years, soil water retention and LLWR were similar under both liming methods.

Tillage system and lime application in a tropical region: Soil chemical fertility and corn yield in succession to degraded pastures

The chemical degradation of soils, due to acidity, and erosion processes, resulting from a traditional tillage system method, are one of the main factors responsible for decreasing the productive capacity of tropical pastures. Thus, establishing the crop-livestock integration system (CLIS) by applying lime on surface without disrupting the soil is interest. The objectives of this study were to evaluate the chemical changes in a soil following surface application or incorporation of lime and to determine the effects of liming on plant nutrition, corn (Zea mays L.) grain yields, and various yield components in cultivated areas of degraded Brachiaria decumbens Stapf pasture. A randomized block experimental design with a split-plot arrangement consisting of two management systems (tillage and no-tillage system) and three lime rates (0.0; 2.7 and 5.4Mgha−1) was used. The highest reactivity of calcium carbonate was observed after six months of liming, since during the sampling time the level of exchangeable Ca2+ and Mg2+ decreased to 0.05m depth, and increased Al3+ and soil acidity to 0.3m. The incorporation of lime did not increase the movement or reaction of the bases in the degraded soil profile. Therefore, surface liming under perennial forage crop residues (B. decumbens Stapf. pasture) provided the best alternative to increase the soil pH index at a depth of up to 0.3m. Macronutrients uptake by plant, yield components, and corn grain yield were not affected by the application method. However, the use of limestone showed viability to maximize up to 20% in corn productivity, regardless of lime rate. The results suggest that it is possible to ameliorate soil acidity and chemical properties of degraded grassland only by surface application of limestone; however, the strategy is considered effective just for soils with no physical restriction to root development.

Revolvimento Ocasional e Calagem em Latossolo Muito Argiloso em Sistema Plantio Direto Consolidado

RESUMO A ocorrência de concentração de nutrientes e compactação superficial tem sido relatada após longo tempo de implantação do sistema plantio direto. O objetivo deste estudo foi avaliar os atributos químicos, a densidade do solo e a produtividade das culturas subsequentes a uma única intervenção mecânica complementada com calagem de um Latossolo Vermelho Distroférrico textura muito argilosa conduzido em sistema plantio direto há 17 anos ininterruptos, em Pato Branco, no sudoeste do Paraná. O delineamento experimental utilizado foi de blocos ao acaso no esquema de parcelas subdivididas, com aração e gradagem do solo nas parcelas (sem e com revolvimento do solo com aração a 0,00-0,20 m e gradagem) e calagem nas subparcelas (sem e com calagem para elevar o índice de saturação por bases a 70 %). Foram avaliados a densidade do solo e a produtividade das culturas de milho (6° mês), biomassa de aveia-preta (12° mês) e soja (20º mês) e os atributos químicos do solo (6° mês). O revolvimento ocasional do solo com aração e gradagem em sistema plantio direto consolidado teve duração efêmera de seis meses na redução da densidade do solo. A incorporação do calcário não apresentou vantagens em relação à sua aplicação na superfície do solo. Não houve aumentos de produtividade das culturas subsequentes à calagem e ao revolvimento do solo. As produtividades das culturas de milho, aveia-preta e soja não dependeram do revolvimento e da incorporação de calcário nessa área agrícola.

Long-term tillage impacts on soil organic matter components and related properties on a Typic Argiudoll

Soil organic matter affects a number of soil processes and properties. A better understanding of soil-profile distribution of organic matter components and related soil properties under long-term tillage systems is thus needed. The objective of this study was to evaluate the impacts of 33 years no-till (NT), double disk (DD), chisel (CH), and plow tillage (PT) under corn (Zea mays L.)–soybean (Glycine max L.) rotation on soil organic C (SOC), particulate organic matter (POM), pH, and wet aggregate stability to 100cm soil depth on a Sharpsburg silty clay loam (fine, montmorillonitic, mesic Typic Argiudolls) in eastern NE. After 33 years, NT and DD management increased SOC by 1.2 times and mean weight diameter (MWD) of aggregates by 2 times compared with CH and PT at the 0–10cm depth. At the 0–20cm, NT had 1.1 times higher SOC concentration than CH and PT. When compared with data collected 24 years prior to this study, SOC at the 0–20cm increased by 12.5% across NT, DD, and CH and by 2.7% for PT. No-till had 5 times higher total POM concentration than PT, 4.7 times higher than CH, and 2.4 times higher than DD at the 0–10cm depth. However, at the 10–20cm, PT had higher POM than other tillage systems, which is most probably due to mixing and burial of residues at the bottom of the plow layer. Soil pH did not differ among tillage treatments at the 0–10cm, but it differed in this order: PT>CH>DD>NT at the 10–20cm and PT=CH=DD>NT at the 20–40cm depth. The lower pH under NT, DD, and CH in deeper soil depths may be due to the limited or no lime mixing in these systems compared with PT. When compared with data (pH 5) collected 33 years prior to this study, soil pH increased by 0.9 in NT, 1.4 in DD, 1.5 in CH, and 1.9 units in PT at 0–20cm depth, probably due to surface application and incorporation of lime. Overall, 33 years of NT increased near-surface soil organic matter components and soil aggregation compared with the PT.

Control of soil-borne pathogen Fusarium oxysporum by biological soil disinfestation with incorporation of various organic matters

Banana Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (FOC) is a worldwide soil-borne disease that causes serious economic losses every year. Effective ways of preventing the disease are still not available. In this study, biological soil disinfestation (BSD) with incorporation of various organic matters under flooding conditions combined with plastic mulching was applied to suppress FOC and prevent banana Fusarium wilt disease. The biological properties of the soil during the BSD process were investigated using quantitative real-time PCR and denaturing gradient gel electrophoresis. The results showed that the values of soil redox potential significantly decreased by >800 mV in the treatments that incorporated rice straw and bagasse under flooding conditions compared with untreated soil. The lowest soil pH (5.36) and a significant decline in the FOC population to 2.79 % of untreated soil were obtained in flooded soil with the highest amount of rice straw. Incorporation of bagasse, pig manure, and lime also significantly decreased the populations of FOC, but were less effective than rice straw. Application of rice straw under flooding conditions significantly increased soil bacterial diversity, and the increased bacteria were considered to have an antagonistic effect on FOC. In 2013 field experiment, a wilt disease control efficiency of 82.3 % was obtained in flooded soil incorporated with 0.5 % (w/w) rice straw compared with untreated soil, and the control efficiency of BSD was further confirmed in 2014 field experiment. These results indicated that BSD can reduce FOC populations in soil, ameliorate soil microbial communities, and reduce the occurrence of banana Fusarium wilt disease.

Corn productivity in function of surface application of lime in differents management systems and cultural preparation

The evaluation of technologies employed at the agricultural production system such as crop rotation and soil preparation, both associated with crop-livestock integration, is crucial. Therefore, the aim of the present study was to evaluate the incorporation of lime for three no-tillage systems and cultural managements in system of crop-livestock integration, with emphasis on corn grain yield. The experiment was conducted from January 2003 to April 2005 at Selvíria city, MS, in Dystroferric Red Latosol, clay texture. The experimental design was randomized blocks with split plots consisted of three main treatments, aimed the soil physics conditioning and the incorporation of lime: PD - No-no-tillage; CM - minimum no-tillage, and PC - conventional no-tillage; and of two secondary treatments related to the management: rotation and crop succession, with four replications. Data on agronomic traits of maize were analyzed: plant height, stem diameter, height of the first spike insertion, 100 grains weight and grain yield. The results showed that the maize produced under the system of crop-livestock integration is quite feasible, showing that grain yields are comparable to averages in the region and the different soil physical conditioning and incorporation of lime did not influence the corn yield as well as the cultural managements, rotation and succession, did not affect the maize crop behavior after two years of cultivation.

Soybean root growth and crop yield in reponse to liming at the beginning of a no-tillage system

Analyzing the soil near crop roots may reveal limitations to growth and yield even in a no-tillage system. The purpose of the present study was to relate the chemical and physical properties of soil under a no-tillage system to soybean root growth and plant yield after five years of use of different types of limestone and forms of application. A clayey Oxisol received application of dolomitic and calcitic limestones and their 1:1 combination in two forms: surface application, maintained on the soil surface; and incorporated, applied on the surface and incorporated mechanically. Soil physical properties (resistance to mechanical penetration, soil bulk density and soil aggregation), soil chemical properties (pH, exchangeable cations, H+Al, and cation exchange capacity) and plant parameters (root growth system, soybean grain yield, and oat dry matter production) were evaluated five years after setting up the experiment. Incorporation of lime neutralized exchangeable Al up to a depth of 20 cm without affecting the soil physical properties. The soybean root system reached depths of 40 cm or more with incorporated limestone, increasing grain yield an average of 31 % in relation to surface application, which limited the effect of lime up to a depth of 5 cm and root growth up to 20 cm. It was concluded that incorporation of limestone at the beginning of a no-tillage system ensures a favorable environment for root growth and soybean yield, while this intervention does not show long-term effects on soil physical properties under no-tillage. This suggests that there is resilience in the physical properties evaluated.

土壤快速强烈还原对于尖孢镰刀菌的抑制作用

香蕉枯萎病是由尖孢镰刀菌古巴专化型（<em>Fusarium oxysporum</em> f. sp. <em>cubense</em>，FOC）引起的一种世界性的土传病害，每年造成大量的经济损失，目前尚未找到有效的防治办法。实验采取土壤淹水及添加有机物料的方法，抑制土壤中FOC的数量。结果表明：土壤淹水处理在第5天显著增加了土壤的pH值，但随着处理时间的增加，淹水的处理中土壤pH值逐渐下降；土壤淹水及添加有机物料显著降低了土壤中SO₄^2-和NO₃^-的浓度；土壤中添加秸秆、猪粪和石灰的处理显著增加了土壤中NH₄⁺的浓度。土壤淹水及添加有机物料对于土壤中可培养细菌数量无显著影响；但显著降低了土壤中可培养放线菌和真菌的数量；土壤淹水及添加秸秆、甘蔗渣和石灰的处理显著降低了土壤中FOC的数量，其中添加高量秸秆处理中FOC的数量下降最多，仅为处理前土壤中FOC数量的2.88%。添加有机物料但未加石灰的处理土壤中总微生物量较处理前相比显著增加。研究表明土壤淹水及添加有机物料是一种可以防控香蕉枯萎病的高效和环保的方法。;Soil-born diseases mainly caused by continuous cropping of monocultures are world-wide problems and seriously restrain the development of contemporary agriculture. Traditionally, farmers use chemical pesticides as a relatively dependable method of protecting plants from soil-borne pathogens. However, increased use of chemical pesticides have several negative effects on the environment and human health and restrictions have increased on use of a variety of chemical pesticides. Therefore, there is an urgent need for effective and environmentally friendly ways to prevent and control soil-borne diseases. Banana fusarium wilt caused by <em>Fusarium oxysporum</em> f. sp. <em>Cubense</em> (FOC) is a kind of world-wide soil-borne diseases and causes serious economic loss every year. The effective ways to prevent the disease are still not available. The experiment was carried out in October 2012. The study site was located in Ledong, Hainan province, China (18°65' N, 107°79' E). The filed used in the experiment was planted with banana for many years, and had a high <em>Fusarium</em> wilt disease incidence of more than 50%. The experiment contained ten treatments, i.e. (1) untreated soil, (2) disturbed soil, (3) flooding disturbed soil, (4) flooding soil incorporated with rice straw at low rate, (5) flooding soil incorporated with rice straw at high rate, (6) flooding soil incorporated with rice straw at high rate plus lime, (7) flooding soil incorporated with pig manure, (8) flooding soil with bagasse, (9) flooding soil with bagasse plus lime, and (10) flooding soil with lime. The soil pH, contents of SO₄^2-, NO₃^- and NH₄⁺, and the populations of bacteria, actinomyces, fungi and FOC of the soils were analyzed at 5, 10, and 15 days after flooding and drained. The results showed that the soil pH in the flooding treatments were raised in the fifth day significantly compared with untreated soils and then became gradually declined over treated time. The contents of SO₄^2- and NO₃^- were decreased significantly, while the content of NH₄⁺ were increased in the soils with straw, pig manure and lime, respectively, under flooding conditions. Flooding the soil incorporated with organic matters significantly reduced the populations of cultivable actinomyces and fungi but not influenced the populations of cultivable bacteria. The populations of FOC were significantly declined in the soils with increasing the rate of incorporated rice straw under flooding condition to 2.88% of untreated soil. Incorporation of bagasse and lime decreased the population of FOC significantly as well, but less effectively than with rice straw did under flooding conditions. Pig manure was not effective to reduce the FOC population. The total amounts of microbe in the treatments applied with organic matters were raised compared with untreated soil. These resluts indicated that anaerobic conditions created by flooding soil incorporated with organic matters not only reduced the FOC population in the soil, but also improved the soil physicochemical properties and microbial communities. It is the first report in China that quickly and intensively anaerobic conditions created by flooding soil incorporated with organic matters effectively reduce the population of plant pathogens within 15 days. Therefore, anaerobic soil disinfection would provide a feasible measure for the control of banana fusarium wilt in agricultural production. Furthermore, the method provides a way to recycling use of crop residues.

Application limestone forms and doses for alfalfa in no-tillage system

Alfalfa (Medicago sativa L.) requires good soil fertility. Brazil is characterized by acidic soils which reduce the potential of the crop. Generally, liming is incorporated into the soil, but in tillage systems it is inadvisable. This study aimed to evaluate the effects of the lime application method and dose on pH, Al+3, V % and Ca+Mg in the soil and on dry matter yield of alfalfa cultivated under a consolidated no-tillage system. The experiment was conducted at the Experimental Station of Parana Agronomic Institute, located in Pato Branco city, in Parana state. The plots consisted of the types of lime application (plowing+harrowing, subsoil and surface), the sub-plots was the lime dose (0, 2, 4, 6 and 8 Mg ha-1) and the sub-sub-plots were the sampled soil depth (0-5; 5-10; 10-20 and 20-30 cm). The results show the application of lime, even superficially, caused increases in pH, concentration of Ca and Mg and base saturation of the soil, while also reducing the concentration of Al, especially in the surface layers of the soil. The practice of plowing and harrowing or of subsoiling, with the aim of lime incorporation in a consolidated no-tillage system is unnecessary. If it is required, the application of lime to the soil should be done superficially for alfalfa cultivated in this system.

Improvement of Characteristics Geotechnics of the Clay Soils by Incorporation of Lime Case of Ouled Fayet and Cheraga

Lime is flexible hydraulics which has the property to improve the soil mechanics characteristics. For the muddy and argillaceous grounds, the traditional interaction between lime and their minerals is noticed immediately. The ground becomes friable and is drained, especially with the quicklime; the mixture can be stored for one short period (a few weeks) without its intrinsic properties not changing. For a good soil stabilization with lime it is necessary to lay out of certain relative data to the soil mechanics properties, like plasticity, granulometry and the water content to evaluate the possibilities for improvement<i>.</i><i> </i>This work consists at the presentation of the results of a laboratory study on the treatment of a clay soil in the area of the Inhabitant of Algiers by incorporation of various contents extinct lime. For that, physical and mechanical tests such as (unconfined compression test, classification tests of the grounds in 1st place and shear test) were carried out and the results obtained highlight an unquestionable and definitely better improvement of the characteristics geotechnics such as the resistance of compression, resistance of shearing (angle of friction and cohesion).

Behavior of the Grounds Inflating of Algiers by Incorporation of Lime "Case of Ouled Fayet and Cheraga"

The ground heaving is a very complex phenomenon which utilizes a great number of intrinsic and surrounding parameters. It is the response of the ground to a gradient of potential of the water of this last. It appears initially by a water run-off within the meaning of Darcy, in the large pores of the ground, then by the hydration of the particles of clay. This phenomenon is related to two parameters of great importance: it water content initial of the ground which expresses the state of suction of the ground and which controls the rate of swelling that it is for the altered or intact grounds. it initial dry density or the index of the vacuums, which measures the quantity of material likely to inflate. Indeed, the curve which giving swelling according to time, reveals two quite distinct phases, one fast which starts with the flood of the sample, the other slow one which evolves/moves in time. According to Chen (1988), the first phase would be the result of a relaxation partial of the constraints in the partially saturated vacuums. This phase would correspond to a macroscopic swelling, compared to a water run-off within the meaning of Darcy, which is governed by the permeability of the medium and the gradient of suction, i.e. a water filling of the large pores separating the grains. The second phase would represent the process of progressive hydration of argillaceous minerals starting from water existing in the pores. Thus starting from this direction, our work, consists in plotting the curves of kinetics of swelling according to time for two natural clay soils of Algiers “Ouled Fayet and Cheraga” with the calculation of the pressures and rates of swelling of the latter in a first place, then by studying the behavior and the improvement of this swelling in this kind of the grounds by adding a hydraulic binder as being one stabilizing which is the lime of Saida.

Ethephon Substrate Drenches Inhibit Stem Extension of Floriculture Crops

Ethephon [(2-chloroethyl) phosphonic acid] is a plant growth regulator that releases ethylene on application and can abort flowers, stimulate branching, and inhibit stem elongation. Although ethephon is used as a foliar spray during the commercial production of many ornamental crops, its effectiveness as a drench has not been widely investigated. We performed experiments to quantify the effects of an ethephon drench on growth and flowering of a range of bedding plant and Narcissus cultivars and to assess the effect of lime on ethylene release from a peat substrate. A substrate drench of 0, 100, 250, or 500 mg·L−1 ethephon was applied to 12 potted Narcissus cultivars at one location, and up to 200 mg·L−1 was applied to 24 cultivars of bedding plants at three locations. Compared with untreated controls, ethephon generally reduced plant height at flowering and the effect increased with increased concentration. For example, Narcissus treated with a 250 mg·L−1 ethephon drench had stems that were 20% to 40% shorter at the end of flowering than control plants. However, ethephon drenches generally caused a 2- to 3-day flowering delay, and two cultivars had a phytotoxic response. Among the bedding plants studied, a 100-mg·L−1 ethephon drench suppressed plant height at flowering by greater than 30% in Catharanthus, Celosia, Dianthus, and Verbena, but by only 10% to 15% in Lobelia, Lycopersicon, and Tagetes. The drenches also delayed flowering in 10 of the 16 crops measured and decreased dry mass accumulation in all of the crops measured. Ethephon release from peat substrate became maximal ≈120 h after application and was dramatically increased by incorporation of dolomitic lime up to a rate of 9.5 kg lime per m3 of peat. Collectively, these studies show that ethephon substrate drenches inhibit stem elongation in a broad range of floriculture crops, but can also delay flowering and reduce biomass accumulation.

Effect of Lime, Inorganic, and Organic Sources on Soil Fertility, Yield, Quality, and Nutrient Uptake of Sweet Potato in Alfisols

Field experiments were conducted in Alfisols to study the effect of integrated use of lime, inorganic, and organic manures on soil health and sweet potato performance. Integrated use of nitrogen, phosphorus, and potassium and farmyard manure recorded a significantly higher tuber yield (18.7 Mg ha−1) followed by lime + farmyard manure + neem cake + green manure (17.7 Mg ha−1). Incorporation of organics and 100% nitrogen, phosphorus, and potassium showed a yield response of 23%, 2%, and 10% in respect of farmyard manure, neem cake, and green manure over nitrogen, phosphorus, and potassium. A yield response of 12%, 10%, and 13% was observed due to incorporation of lime along with ½ nitrogen, phosphorus, and potassium and organics (farmyard manure, neem cake, and green manure) over that of unlimed plots. Conjunctive use of organic manures along with balanced fertilizers and lime not only produces higher crop yields but also enhanced the efficiency of added nutrients and sustains the soil fertility.

The effect of lime and compost amendments on the potential for the revegetation of metal-polluted, acidic soils

The revegetation of soils affected by the historic pollution of an industrial complex in central Chile was studied. Spontaneous and assisted revegetation and changes in the physicochemical properties of the soils were evaluated in field plots that were amended with lime or lime + compost. Lime had no effect on plant productivity in comparison with the control, whereas the incorporation of lime + compost into the soil increased the plant cover and aboveground biomass. The application of lime + compost increased the plant productivity of Chrysanthemum coronarium (a species sensitive to the atmospheric emissions from the industrial complex), thus showing effective in situ stabilization of soil contaminants. Regression analyses suggested that the plant response was due to the increase in the soil organic matter content rather than to the increase in the soil pH. The aboveground biomass and plant cover did not differ under the spontaneous and assisted revegetation regimes. The native soil seed bank was sufficient for attainment of the proper plant cover and biomass production after the application of the soil amendments. Although the pCu 2+ in the amended soils was 4 orders of magnitude higher than in the unamended control, the shoot Cu concentration was similar among most of the combinations of plant species and amendments.

Effects of lime and sewage sludge on soil, pasture production, and tree growth in a six‐year‐old Populus canadensis Moench silvopastoral system

AbstractIn many regions worldwide, silvopastoral systems are implemented to enable sustainable land use allowing short, medium, and long‐term economic returns. However, the short‐term production in silvopastoral systems is often limited due to nonappropriate soil‐fertility management. This study evaluated the effects of two doses of lime (0 and 2.5 t CaCO3 ha–1) and three sewage‐sludge treatments (0, 200, and 400 kg total N ha–1 y–1 applied in 2 consecutive years) on soil characteristics (soil pH, soil organic matter [SOM], soil nitrogen, cation‐exchange capacity [CEC]), pasture production, and tree growth in a silvopastoral system of Populus × canadensis Moench in Galicia, northern Spain during 6 years after establishment. Soil pH increased during the experimental period for all treatments, although this effect was more pronounced after lime application. Changes in SOM and soil nitrogen content were not consistent over time, but sewage‐sludge application seemed to result in higher values. Higher CEC was found for treatments with lime and sewage‐sludge application. Following incorporation of lime and sewage sludge, pasture production was significantly enhanced (cumulative pasture production 51.9 t DM ha–1 for Lime/N400 compared to 39.0 t DM ha–1 for No lime/N0). This higher pasture production also affected tree growth due to more severe competition between pasture and tree resulting in slower tree growth. Liming and application of sewage sludge are relevant measures to improve soil fertility and thereby optimizing the overall production of silvopastoral systems. However, it is important not to overintensify pasture production to ensure adequate tree growth.

Componentes da produção e produtividade de cultivares de arroz e feijão em função de calcário e gesso aplicados na superfície do solo

A utilização do gesso agrícola e de cultivares mais tolerantes à acidez do solo podem ser alternativa para viabilizar o cultivo em sistema plantio direto sem a incorporação prévia do calcário. Este trabalho foi realizado com o objetivo de avaliar o efeito da aplicação superficial de calcário e gesso agrícola nos componentes da produção e na produtividade de grãos de cultivares de arroz e feijão. O experimento foi instalado em Latossolo Vermelho distroférrico, anteriormente manejado no sistema convencional de preparo do solo, em Botucatu (SP). O delineamento foi em blocos casualizados com parcelas sub-subdivididas e quatro repetições. Nas parcelas, os tratamentos foram os seguintes: quatro doses de calcário dolomítico (0, 1.100, 2.700 e 4.300 kg ha-1); nas subparcelas, aplicação ou não de 2.100 kg ha-1 de gesso agrícola; e nas sub-subparcelas, foram cultivadas duas cultivares de arroz de terras altas (Caiapó e IAC 202), no ano agrícola 2002/2003, e duas de feijão (Pérola e Carioca), em 2003/2004. O número de panículas por m², o número de espiguetas por panícula, a massa de mil grãos e a produtividade de grãos das cultivares de arroz aumentaram pela aplicação de calcário. A aplicação de gesso aumentou o número de panículas por m² e a produtividade de grãos da cultivar Caiapó, mas reduziu o número de panículas e não afetou a produtividade da cultivar IAC 202. A calagem, na ausência de gesso, aumentou o número de vagens por planta e a produtividade de grãos das cultivares de feijão. A aplicação de gesso reduziu o número de vagens por planta da cultivar Carioca de feijão, mas não alterou outros componentes da produção e a produtividade de grãos. A dose de calcário para elevar a saturação por bases a 70% foi a mais adequada para ambas as culturas. O uso de cultivares mais tolerantes à acidez do solo proporciona maior produtividade no início do sistema plantio direto, quando ainda não houve efetiva correção do solo pela aplicação de corretivos em superfície.

Sugar-Beet-Processing Lime as an Amendment for Low pH Soils

In the Red River Valley, about 385,000 Mg of lime is used to help refine about 39,000 Mg of sugar beets. In a greenhouse study, sugar-beet-processing lime (spent lime; SL), commercial ag lime (AL), and reagent-grade lime (RL) were added to an acidic soil at rates of 0, 1.96, 3.93, and 7.86 Mg ECC ha−1. Wheat was planted, and aboveground biomass and root masses were determined after 44 d of growth. Soil pH increased the greatest with the highest lime application rates. Incorporation of lime uniformly increased soil pH in the pots, whereas with surface application, soil pH decreased with increasing depth. The SL yielded more aboveground soil biomass and root mass than the AL and RL. Use of SL for increasing soil pH and reducing exchangeable Al in acid soils would be a viable use for this industrial by-product.