Role Of Lime Research Articles

Liming mitigates the spread of antibiotic resistance genes in an acid black soil

The threat of antibiotic resistance genes (ARGs) caused by animal manure application to human health has been the focus of attention in agriculture. Applying lime to acid soil for the amelioration of soil acidity is a prevailing agricultural practice. However, the role of lime on the spread of antibiotic resistome from soil to plant is unknown. In this study, a pot experiment of lettuce was established in the acid black soil with lime addition at the rate (w/w) of 0%, 0.08%, 0.16%, and 0.32% of the total soil mass to explore the transmission of ARGs introduced by the fresh poultry manure in the soil-plant system. The bulk and rhizosphere soils as well as the leaf samples were collected after lettuce was cultivated for 60 days, the bacterial community and antibiotic resistome in these samples were determined by using Illumina sequencing and high-throughput quantitative PCR (HT-qPCR) methods, respectively. Results showed that lime application decreased the number and abundance of ARGs and slowed down the spread of manure-derived ARGs in the soil-plant system. The ARGs and bacterial community composition were significantly varied among bulk soils, rhizosphere soils and leaf endophyte, and also influenced by lime within the same sampling types. The structural equation model further demonstrated that the lime addition had a negative effect on ARG diversity, which was also indirectly regulated by bacterial community diversity. These findings suggest that lime addition can alleviate the level and dissemination of ARGs in soils and provide a potential measure to control the spread of ARGs derived from animal manure.

Review on role of lime on soil acidity and soil chemical properties

One of the chemical soil degradation difficulties which affect soil production in the Ethiopian highlands is due to soil acidity. These review efforts to put together soil acidity concept, causes extent and management practices. Soil acidity is the problem of agricultural activities in Ethiopian highlands or cultivated lands and is getting an increase. To adjust acid soils and increase yields of crops of their choices farmers need simple and supportable methods, such as liming. An important role for raising soil pH and enhancing crop productivity liming has play an important role. In Ethiopia, because of soil acidity and associated toxic nutrient availability the gap between probable and actual yield is very varied .The application of mineral fertilizers without adjustments is simply wastage of resources, because acidic soils are not reactive those mineral fertilizer. Improving yield production and there by satisfying yield gains effective and efficient acid soil management practices is important .This review emphases on the role of liming on soil chemical properties and also causes and managements of soil acidity and its successive effect on soil fertility and crop yield, in addition to this Integrated acid soil management improves the permanence of yields and maximizes nutrient use efficiency

The role of lime in dredged mud dewatered by a plate and frame filter press and potential substitutes.

Dredged mud is a kind of construction material that can be reused as waste. It needs to be dehydrated before it is used. At present, plate and frame pressure filtration (hereafter referred to as PFP) using lime for conditioning after flocculation is widely employed. The addition of lime causes the mud cake to exhibit a high pH, and reduces its subsequent use. In response to this problem, this study examines the mechanism of lime in the PFP and identifies neutral alternative materials according to this principle. British kaolin-modified mud and dredged Taihu mud were treated with lime and various conditioners, and the size and specific resistance (hereafter referred to as SRF) of the floc were measured to evaluate the mud's properties, the compressibility index of the mud layer, the dewatering effect of the PFP, and the properties of the cake. The results showed that lime ensures the filtration speed in the pumping-filtering phase by increasing floc stiffness and reducing the compressibility of the layer, so that continuous drainage can achieve a high-pressure filtration efficiency. SAC can basically achieve the same pressure filtration principle and dewatering effect as lime under conditions in which the pH of the mud cake is close to neutral.

The need for lime in dependence on clay content in arable crop production in Germany

Liming is a well-established practice to ameliorate acidic soils worldwide. However, the role of liming in soil structure formation and its relation to the nitrogen cycling is only little explored. We hypothesized that improved physical and mechanical soil properties, which are directly linked to soil structure, lead to lower nitrogen losses in an agricultural system. Water holding capacity, total pore volume, bulk density, hydraulic conductivity, shear stress and pre-compression stress were quantified in the topsoil of three surveys located in Germany on different soil types: Eutric Gleyic Cambisol (Loamic) (Magdeburg, Saxony-Anhalt), Haplic Luvisol (Neubrandenburg, Mecklenburg-Western Pomerania) and Eutric Cambisol (Loamic) (Puch, Bavaria). The field experiments were arranged in a Randomized Complete Block Design and treated with two different rates of lime (calcium carbonate). Furthermore, three rates of nitrogen in form of urea or calcium ammonium nitrate were applied every year. Liming significantly increased the pH, plant available water capacity, total pore volume and decreased bulk density in the soils six months after application, but twelve months after lime application the soil structure collapsed again causes by ploughing and chiseling. We, therefore, assume a positive influence of lime application on soil physical parameters, if tillage is excluded at least initially. On the other hand, our results from the shear stress parameters and the pre-compression stress values indicate that their changes need time and we assume that it may take several years to develop a sustainable structure system.

Influence of Neutralization on Hydration of Hemihydrate Phosphogypsum Plaster

Effect of lime on hydration of hemihydrate phosphogypsum (HPG) plaster were investigated aiming at neutralizing HPG since it was obtained by calcining phosphgypsum without any purification. Results showed that neutralization would lead to retardation and strength degradation, particularly with small amounts of lime (0.1%-0.4%). As a result, the role of lime in HPG plaster can be described as 1) reacting with impurities in HPG and the reactant would affect the dissolution of HPG, gypsum nucleation and growth; 2) increasing ion concentration and supersaturation by excessive lime which can promote the hydration again. The gypsum crystal changed from needle-like to tiny crystal with little interlocking and then long prismatic crystal with comparable strength due to the mechanism of lime. Therefore, sufficient lime is needed for neutralization which is economic and beneficial for the application of HPG.

Role of lime, fly ash, and slag in cement pastes containing recycled concrete fines

Construction and demolition waste recycling for production of new concrete is usually limited to the use of coarse aggregates, and efficient utilization of fine subsieve fractions remains an unresolved issue. In the presented research, Portland cement pastes containing 50% finely ground recycled concrete, blended with lime, fly ash, or blast furnace slag, were studied. SEM-BSE microscopy, EDX analysis, and porosimetry were employed for investigating their microstructure, individual stages of hydration were detected using calorimetry, shrinkage was optically monitored in the early stages of hardening, the evolution of Young’s modulus was assessed using the resonance method, and strength was determined from destructive tests. The study suggests that recycled concrete fines can be incorporated into cementitious composites in large amounts and even improve their properties, especially when blended with fly ash or blast furnace slag. Substitution of Portland cement in the studied pastes by recycled concrete led to a compressive strength deterioration, but also a reduction of shrinkage, and an increase of the tensile strength in bending by up to 26%.

Role of lime with cement in long-term strength of Compressed Stabilized Earth Blocks

Compressed Stabilized Earth Blocks (CSEBs) are manufactured using stabilizers to provide adequate compressive strength and durability, so, as to make them suitable as building blocks. Though cement is a popular stabilizer used in manufacture of CSEBs, no study has been reported utilizing lime in combination of cement. This experimental study on CSEBs prepared using lime as a replacement to cement in certain proportions has clearly brought out the effectiveness of lime with cement in improving the long-term build-up of strength better than using cement alone. It was observed that blocks prepared with optimum quantity of lime along with cement has led to continuous buildup of strength even beyond 2 years, whereas blocks prepared with cement alone and lesser quantity of lime than optimum quantity have not gained much strength after 6 months from the time of preparation of the blocks. The research findings show a need to relook at the grading of ingredients and quantity of stabilizers for achieving good building blocks. This would be an added benefit not only in reducing the cost of the blocks, but also has serious implications in terms of the reduction of energy consumed in the manufacture of blocks when done in large scale.

Behaviour of lime–slag-treated clay

This paper describes the strength and microstructural behaviour of lime–slag-treated clay. The microstructure was investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the strength of the treated clay was measured using the unconfined compressive strength (UCS) test. Untreated clay was prepared in the laboratory by mixing commercially available kaolin and bentonite, while hydrated lime and ground granulated blastfurnace slag (ggbs) were used as binders. XRD analyses of lime–slag-treated clay showed the existence of numerous reaction products such as calcium silicate hydrate (C–S–H), calcium aluminium silicate hydrate (C–A–S–H), and hydrotalcite (HT), which facilitated the strength increment. For a fixed proportion of lime, the relative intensity of pozzolanic reaction products was found to increase with increasing slag content. Slag was found to be very active to promote the pozzolonic reaction with lime, as evidenced from the presence of crystalline reticular (C–S–H) and platy (C–A–S–H) cementitious products in the SEM images. The role of lime in the activation of slag was also seen to have an upper limit whereby excess proportions failed to provide significant additional benefit. The UCS of lime–slag-treated clay was found to be higher in comparison with lime or slag alone with the same replacement ratio. This was due to the formation of more crystalline cementitious products, which accelerated the bridging (cementation) effect between lime–slag and clay particles.

Effect of lime content on the processing conditions of cooked maize tortillas: changes of thermal, structural, and rheological properties

Basic data on thermal, dielectric, and IR spectral properties of cooked tortillas were investigated with the major aim to understand the role of lime, Ca(OH)2, incorporated during the alkaline cooking process. The data are further supplemented by x-ray diffraction and texture mea- surements. The changes in the thermal diffusivities, measured by the photoacoustic technique, as well as the changes in texture, x-ray pat- terns, dielectric, and IR spectral properties are presented as a function of the lime concentration. The results show strong evidence that there is a marked concentration of lime (around 0.2%) above and below which different behavior patterns of the measured properties of tortilla were observed. In particular, the results for the dielectric constant and thermal diffusivity provide strong evidences for enhanced starch crosslinking tak- ing place for lime content close to 0.2%. © 1997 Society of Photo-Optical In- strumentation Engineers.

Role of lime in the generation of reactive oxygen species from betel-quid ingredients.

The role of lime in the formation of reactive oxygen species (ROS), i.e., O2-., H2O2, and OH., from betel-quid components (extracts of areca nut and catechu) was investigated in vitro using a chemiluminescence technique and an assay for oxidative DNA damage involving analysis of 8-hydroxy-2'-deoxyguanosine. Of the various areca-nut extracts, the catechin fraction, at alkaline pH, was shown to be the most active producer of ROS. The free Ca(OH)2 content and pH of lime samples (a component of betel quid and chewing tobacco) were highly correlated with the generation of ROS from areca-nut extract in vitro and with oxidative base damage to DNA in vitro. While Fe2+ had an enhancing effect on ROS formation, Mg2+ had a marked inhibitory effect. The cytogenetic effects of ROS generated in vivo were measured in Syrian golden hamsters in which the cheek pouch had been painted with lime and an areca-nut extract or catechu, singly or in combination. The frequency of micronucleated cells was increased only in animals that had received both the areca-nut extract and lime. The frequency of micronucleated cells in exfoliated oral mucosal cells from Indian chewers of betel quid with tobacco containing lime or of tobacco with lime was significantly higher than in a control (no habit) group. These studies demonstrate that addition of lime to betel quid constituents generates ROS, which induce cytogenetic damage in hamster cheek pouch and may contribute to the cytogenetic damage observed in the oral cavity of betel-quid chewers. These results implicate ROS in clastogenesis and probably in the etiology of oral cancer.

Role of Lime in the Generation of Reactive Oxygen Species from Betel-Quid Ingredients

Role of Lime in the Generation of Reactive Oxygen Species from Betel-Quid Ingredients

Finishing off – using limewash and distemper in old buildings

Discusses the identification, treatment and application of the right finishes to early buildings, with particular emphasis on lime‐based materials. Examines the role of lime in historical building construction and the lime cycle. Outlines limewash varieties and looks at its traditional use, mentioning its advantageous ability to breathe and cut down on condensation problems. Describes removing old paint and the appropriate use of distemper. Suggests that despite drawbacks, lime‐based materials are cheaper and more enjoyable to use than modern equivalents.

Effect of parent material, natural available soil boron, and applied boron and lime on the growth and chemical composition of lucerne on some acidic soils of the Central Tablelands of New South Wales

Fifteen acidic soils (0-1 5 cm), three from each of the five main parent materials in the Central Tablelands of New South Wales, were collected for a glasshouse experiment. The hot water soluble boron content of these soils and some other related soil properties were measured. Boron at nil and 1.5 �g/g air-dried soil and lime at nil and 670 �g/g air-dried soil in a factorial combination were applied to the soils. The effects of the treatments on the performance of lucerne (Medicago sativa cv. Hunter River) grown on these soils were studied. Boron application tended to increase the production of lucerne dry matter on sandstone, shale and slate, and granitic soils, but not on basaltic or alluvial soils. Also, it increased the boron concentration in the leaves of lucerne grown in all soils and consequently, reduced the calcium to boron ratio. The boron levels that produced 90% of the maximum yield and below which boron deficiency symptoms were manifested by the plants, were 0.34 �g/g in air-dried soil and 25 �g/g in oven-dried leaves. There was a linear correlation (r = 0.98) between the hot water soluble boron content of the untreated soils and the boron concentration in the leaves. The hot water soluble boron content of the soils derived from sandstone, shale and slate, and granite was much lower than the basaltic or alluvial soils and were nearly equal to or below the determined critical level. Although liming had the tendency to induce the symptoms of boron deficiency, the effect of lime was greater than boron in increasing the yield. The role of lime in eliminating the problems of these acidic soils and hence promoting the yield of lucerne is discussed.

Nutrient problems in sown pasture on an acid soil. 2. Role of lime and superphosphate

A study was made of the role of superphosphate and lime on subterranean clover (Trifolium subterraneum) production on an infertile acid soil in pot culture. Both fertilizers increased the exchangeable calcium in this deficient soil. Lime and superphosphate were involved in nodulation of the clover plants. There was no evidence of the direct involvement of either of them in the nitrogen fixation process, but they did increase nitrogen uptake by the plants. Once the legume functioned adequately, full expression of the yield response to phosphorus on this deficient soil followed. Most efficient phosphorus use occurred at the lime 1255, superphosphate 2000 kg ha-1 level (lime 1/2, P 16). Heavy lime dressing reduced exchangeable magnesium and the phosphorus available to the plant. Aluminium and pH were involved in the effects observed. Lime reduced CaCl2-extractable aluminium and the titratable acidity in the soil. Phosphate increased the CaCl2-extractable aluminium and apparently reduced the titratable aluminium. The combined treatments reduced these three attributes and promoted increased plant growth. Increased plant growth was associated with increased aluminium uptake by the plants, which suggests that the real effect of aluminium may have been on the calcium and phosphorus uptake by the plants, rather than on the toxic nature of the element itself.

Calcium problems in Latin America

Abstract A general discription of soil characteristics of Latin America is given with emphasis being put on the oxisols of the subtropical and tropical regions; the relationships among pH and degree of Al and Ca saturation is presented; special mention of the cerrado soils of Brazil is made. Calcium requirements of main crops are tabulated. A review is made of known cases of Ca deficiency under field or green house conditions with an attempt to differentiate between Ca responses and other effects of liming and/or fertilization on observed crop responses. Losses by leaching, erosion, and crop removal of Ca are estimated; a rough balance sheet of inputs and outputs is presented. Trends in fertilizer use and technology in Latin America are discussed with regard to the Ca economy of the region; the role of liming is assessed.

Desulfurizing iron-carbon melts with lime under reduced pressures

Experiments were carried out to compare the rates of formation of CaS on CaO crystals which were either immersed in a sulfur-bearing, carbon-saturated iron melt or held in the effluent gases just above the melt. Temperatures ranged from 1375°C to 1600°C, and times ranged from one to twelve hours. The CaS layers were measured both metallo-graphically and with an electron microprobe. Data on the time and temperature dependence of the layer thickness are presented. These layers were about 15 microns thick after 6 h at 1460°C, independent of whether or not the crystal was immersed in molten iron. The role of lime in the desulfurization process is to act as a getter for removal of sulfur from the gas stream.

Histological changes in the oral mucosa of the wistar rat treated with commercial lime (calcium hydroxide)--an optical and submicroscopic study.

The high incidence of oral cancer in different population groups in many south-east Asian nations has been stressed repeatedly in early and recent reports (Orr, 1933; Balendra, 1949; Cooray, 1944; Khanolkar, 1959; Muir, 1962; Pindborg, 1965). In India, and elsewhere, epidemiological and biological investigations have been done, or are in progress, on any possible correlation between the habitual use of the betel chew or pan and oral cancer. The involvement of the main constituents of pan -betel leaf (Piper betel), betel nut (Areca catechu), tobacco (Nicotiana tabacum), slaked shell or stone lime (slaked calcium hydroxide) and catechu (Acacia catechu) have also been considered individually or in combination (Mody and Ranadive, 1959; Muir and Kirk, 1960; Dunham, Muir and Hamner, 1966). The role of lime appears rather controversial, though some reports do suggest its correlation with the occurrence of oral cancer. It was therefore considered worthwhile to study the effects of slaked commercial lime on the oral mucosa of laboratory animals. The main aims of the study were to evaluate the part played by lime in the causation of oral malignancy or of oral conditions considered to be precancerous and the trauma it caused to epithelial and subepithelial tissue. This paper reports the histological changes produced on short term and prolonged application of lime to the oral mucosa of normal, diet conditioned and hormone treated Wistar rats.

Studies on the mechanism of biological nitrogen fixation

The role of lime in the fixation of atmospheric nitrogen by the mixed flora of the soil has been studied. It has been found that consequent on the decomposition of sugar, there is much production of acid that neither a dilute solution of buffer nor periodical addition of alkali helps to maintain the medium at the optimum reaction. In presence of excess calcium carbonate, the acids are neutralised as fast as they are produced with the result that the medium continues to remain neutral and the fixation proceeds unimpaired. Strontium carbonate can replace the calcium salt in the nitrogen fixing medium. Barium or magnesium carbonate is not so useful. Addition of minute quantities of calcium sulphate helps to improve the fixation.

The Role of Lime in Tanning1

The Role of Lime in Tanning¹