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In this study, the effects of chemical (20:20:0 compound) and organic (barnyard) fertilizers applied to different textured soils on several soil enzyme (urease, acid phosphatase, alkaline phosphatase, and dehydrogenase) activities were investigated. The research was conducted under greenhouse conditions with (beans and corn) and without crops. Considering the results of the preexperiment analysis of the soils, a 40-g pot–1 of farmyard manure was placed into the pots in which organic fertilizer would be applied in clay and silty loam soils, and a 50-g pot–1 of farmyard manure was added to sandy loam soil; in addition, a 0.25-g pot–1 of 20:20:0 compound fertilizer was mixed into the clay, silty, and sandy loam samples where chemical fertilizer would be applied. Soil chemical properties such as soil reaction (pH), electrical conductivity, lime, organic matter, useful phosphorus, total nitrogen, exchangeable cations (Ca, Mg, Na, K), cation exchange capacity, microelements (Fe, Cu, Mn, Zn), and soil enzymes (urease, acid phosphatase, alkaline phosphatase, and dehydrogenase) were determined. According to the results, fertilizers applied to the soil increased the soil’s pH, organic matter, and macro and micronutrient contents and decreased the exchangeable Na content. The lime content of the soils did not show any decrease or increase. Organic and chemical fertilizers applied to the soil increased the activity of soil enzymes (urease, acid phosphatase, alkaline phosphatase, and dehydrogenase). [ABSTRACT FROM AUTHOR]

The longevity of a single 22.4 Mg·ha−1 application of dolomitic limestone at four northern hardwood stands was evaluated over 30 years (1986–2016) to determine whether changes in soils, foliage, and tree growth were sustained on the unglaciated Allegheny Plateau in northern Pennsylvania, USA. In limed plots, soils, sampled to 45–55 cm depth, and sugar maple (Acer saccharum Marsh.) and black cherry (Prunus serotina Ehrh.) foliage had significantly (P ≤ 0.05) greater concentrations of calcium (Ca) and magnesium (Mg) through 2016 compared with samples from unlimed plots. Ca and Mg capitals (g·m−2) in the Oi through A horizons combined were greater on limed plots than unlimed plots, largely due to increases in the thickness and nutrient concentration in the A horizon. Over 30 years, sugar maple basal area increment (cm2·year−1 BAINC) was greater in limed plots (30.6 cm2·year−1 vs unlimed 13.3), American beech (Fagus grandifolia Ehrh.) BAINC was unaffected by lime application, and black cherry BAINC was reduced in limed plots compared with unlimed plots. The sustained effect of this one-time lime treatment shows the strong role of efficient nutrient cycling in forests and suggests that the benefits over a substantial portion of a stand rotation may increase the feasibility of operational liming. [ABSTRACT FROM AUTHOR]

We characterized soil bacterial and archaeal communities under native Cerrado vegetation and their responses to increases in soil pH. The experimental area was subjected to lime additions for eight consecutive years, followed by an 11-year interval and an additional lime application. We collected soil samples in the rainy and dry seasons of 2017 (representing the 11-year interval from the last liming) and 2018 (representing short-term effects, 4 and 9 months after we resumed the liming). We studied the microbial communities of soil samples from control and treatment plots (liming) through 16S rRNA gene sequencing. We found that microbial community profiles differed by treatment and sampling period, suggesting long-term effects of liming and the strong influence of Cerrado's seasonal dynamics. Samples from liming treatment had a higher bacterial diversity than the control treatment, while the archaeal community showed the opposite response with lower diversity. Different from diversity estimators, enzyme-encoding genes for C, N, and S metabolic pathways showed a reduction in abundance in the liming treatment. The effects of liming on the soil microbial community under Cerrado vegetation are long-lasting. Despite the increase in diversity, the predicted functional profiles suggested a potential reduction on soil multifunctionality. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) accumulation in rice is strongly controlled by liming, but information on the use of liming to control Cd accumulation in rice grown in slightly acidic soils is inconsistent. Here, pot experiments were carried out to investigate the mechanisms of liming on Cd accumulation in two rice varieties focusing on two aspects: available/exchangeable Cd content in soils that were highly responsive to liming, and Cd uptake and transport capacity in the roots of rice in terms of Cd accumulation-relative gene expression. The results showed that soil availability and exchangeable iron, manganese, zinc and Cd contents decreased with increased liming, and that genes related to Cd uptake ( OsNramp5 and OsIRT1 ) were sharply up-regulated in the roots of the two rice varieties. Thus, iron, manganese, zinc and Cd contents in rice plants increased under low liming applications but decreased in response to high liming applications. However, yield and rice quantities were only slightly affected. These results indicated that Cd accumulation in rice grown in slightly acidic soils presents a contradictory dynamic equilibrium between Cd uptake capacity by roots and soil Cd immobilisation in response to liming. The enhanced Cd uptake capacity under low liming dosages increases risks to human health. [ABSTRACT FROM AUTHOR]

Natural grasslands are important reservoirs of animal and plant biodiversity and provide several ecosystem services, through the action of soil microorganisms. The increased demand for food, energy, and cattle activity has led to the conversion of natural grasslands to cultivated systems. However, the consequences of this conversion for soil microbial diversity and ecosystem functioning are yet to be discovered. Here, we used the 16 S rRNA amplicon sequencing and a large set of soil and environmental variables to understand the possible effects of natural grasslands to cultivated pasture conversion on the soil microbial structure, composition, diversity, and functions. The study areas followed a gradient of increasing soil disturbance intensity, as follows: Natural grassland (NG), Improved-natural grassland (IG), Perennial-cultivated pasture (PP), and Annual-cultivated pasture (AP). Natural grassland conversion to managed and cultivated pastures decreased the abundances of Acidobacteria and Verrucomicrobia, while increased α-, γ-, and δ-Proteobacteria, Gemmatimonadetes, Bacteroidetes, Patescibacteria, and Latescibacteria. The predicted functional profiles have also changed, as functions like 'cellulolytic and symbionts/parasites' decreased after natural to cultivated pastures conversion, while 'nitrogen respiration', 'sulfur respiration', and 'aromatic compound degradation' functions increased. Aboveground plant diversity decrease influenced belowground microbial diversity. The main drivers of diversity, composition, and functional potential are associated with soil attributes affected by liming, like aluminum complexation. In conclusion, we have found taxonomic and functional differences between natural and managed grasslands (NG and IG, respectively) and cultivated pastures (PP and AP), with consequences for management strategies and biodiversity conservation priorities. [Display omitted] • Pasture management intensification shifts soil microbiome diversity and composition. • Liming rules soil microbial diversity and functions changes across pastures. • Forage diversity also drives soil microbial diversity and functional potential. [ABSTRACT FROM AUTHOR]

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 (4.8 Mg ha −1 ) that had either been incorporated (0–20 cm) 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 0–5 cm 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 5–10 cm 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. [ABSTRACT FROM AUTHOR]

The harmful elements monitoring, particularly Cd, have become important for environmental protection. Very low concentrations of Cd in dry matter of plant tissues were found under non-polluted environment of the eastern Croatia. With that regard, differences were found in maize leaves as affected by soil type (averages of ten hybrids) from 0.09 and 0.14 ppm Cd, for acid and neutral soil (pH in KCl 4.10 and 6.81), as well as among genotypes from 0.07 to 0.18 ppm Cd. Grain-Cd in maize were considerably lower and below detection limit (<0.02 ppm Cd). Liming is usual recommended management practice for acid soils fertility improvement. Beside effects on crop yields, liming is useful management practice for decreasing Cd transfer into food chain. In the liming experiment on acid soil, we found in maize leaves (2-year averages) 0.17 and 0.09 mg Cd kg–1, for control and averages of four liming treatments, respectively. Differences were found also between two growing seasons (0.10 and 0.07 ppm Cd, respectively). Also, considerably impact of liming on decreases of Cd in alfalfa hay was found (0.113 and 0.047 ppm Cd, for 0 and 20 t·ha–1 of lime). [ABSTRACT FROM AUTHOR]

The aim of these studies was to determine the effect of soil contamination with nickel (0, 75, 150 and 225 mg Ni kg-1 soil) on the content of nickel in biomass of cocksfoot and fractions of this metal in the soil under different liming (0 Ca and Ca by 1 hydrolytic acidity) and fertilization with organic materials (without the use of organic materials, straw rye and brown coal from Turow Coal Mine). Four swaths of cocksfoot gathered in the third year of a pot experiment were analyzed and fractions of nickel in the soil after the last swath of test plants were determined. Total nickel content in the plant and in the soil was determined by ICP-AES after earlier mineralization. Fractions of nickel in the soil were determined by sequential fractionation according to BCR procedure. The introduction of nickel into the soil, regardless of amount, significantly increased concentration of this metal in the biomass of cocksfoot and soil in all fractions, in particular the soluble and easily exchangeable fraction (F1). Liming the soil and the application of organic materials decreased nickel content in the biomass of cocksfoot and its soluble fraction in soil, easy available for plants, causing the same time to increase its share in the residual fraction (liming) and oxidisable fraction (the application of organic materials). [ABSTRACT FROM AUTHOR]

Productivity of resources on acid soils occupying one fourth of the total area in India is abysmally low. Lime is applied to such soils with the primary objective of increasing the productivity of crops by enhancing the availability of native and applied plant nutrients. Greenhouse pot experiments and laboratory experiments were conducted to evaluate the effects of lime and boron (B) on the availability of nutrients in soils and their uptake by plants. The application of lime enhanced the available nitrogen (N,), phosphorus (P), calcium (Ca), magnesium (Mg), sulfur (S), and zinc (Zn) content in soils, which was reflected in their uptake by sunflower (Helianthus annus). On the contrary, availability of copper (Cu), iron (Fe), and manganese (Mn) in soil was reduced due to liming. Sunflower responded very well in terms of dry matter yield to B application to the extent of 175% and 188% under 1 and 2 mg kg−1applied levels of B, respectively. Dry matter yield of sunflower was reduced to the tune of 29.2 and 42.7% under 2/3 and 1 lime requirement (LR), respectively, over control. Lime application at 1/3 LR with 2 mg kg−1of applied B emerged as an optimum combination in acid soils. [ABSTRACT FROM PUBLISHER]

Abstract: Nitrous oxide (N2O) emissions in semi-arid regions are often greater following summer rainfall events when the soil is fallow, than in response to N fertiliser applications during crop growth. Nitrogen fertiliser management strategies are therefore likely to be ineffective at mitigating N2O emissions from these cropped agricultural soils. Here we examined the influence of raising soil pH on N2O emissions, nitrification rates, and both nitrifier and denitrifier populations following simulated summer rainfall events. The soil pH was raised by applying lime to a field site 12 months before conducting the laboratory experiment, resulting in soil of contrasting pH (4.21 or 6.34). Nitrous oxide emissions ranged from 0 when the soil was dry to 0.065 μg N2O–N g dry soil−1 h−1 following soil wetting; which was attributed to both denitrification and nitrification. Increasing soil pH only decreased N2O emissions when losses were associated with nitrification, and increased amoA gene copy numbers. We propose increasing soil pH as a strategy for decreasing soil N2O emissions from acidic soils following summer rainfall in semi-arid regions when emissions result from nitrification. [Copyright &y& Elsevier]

Abstract: The aim of this study was to identify the effectiveness of liming in combination with vegetation for the recovery of slightly acidic, saline soils of eutrophic wetlands affected by mine wastes, under fluctuating flooding conditions. Simulated soil profiles were constructed and four treatments were assayed under greenhouse conditions: control, only plant, only liming, and liming and plant. The plant species was the halophyte Sarcocornia fruticosa. Three horizons were differentiated: A (never under water), C1 (alternating flooding-drying conditions), and C2 (always under water). The pH, Eh, salinity, and the concentrations of dissolved organic carbon and soluble metals were measured regularly for 18 weeks. Liming favoured the growth of S. fruticosa, an increase in pH and a fall in Eh. The amendment was effective for reducing Mn, Zn, and Cd in pore water of bare soils, but not Cu and Pb. In the treatment with liming and plant, the growth of S. fruticosa counteracted the effect of the amendment, strongly increasing the concentrations of metals in pore water and distributing them along the soil profile. Hence, the combined use of liming and plants may increase the risk of metals mobilisation. [Copyright &y& Elsevier]

In conditions of combined field experiment the influence of liming with Ca(OH)2 in rates of 1,0, 2,5 and 5,0 t/ha on the input of nitrogen, phosphorus and potassium in the leaves of fertility vines from varieties Sauvignon Blanc, Chardonnay, Cabernet Sauvignon and Merlot, planted on Chromic luvisol was studied. Samples were collected in three consecutive years; the first sampling time is 15 months after the incorporation of lime into the soil and the second and third -- at intervals of 12 months. The highest content of iron is absorbed by the Cabernet Sauvignon -- the average for all variants for this variety exceeds by nearly 50% the iron adsorbed by Sauvignon Blanc and by 40% - by Merlot variety. The relationship between iron absorption and rate of applied lime appears relatively clear at high lime rates -2,5 and 5,0 t/ha. For Merlot variety the opposite trend is found -- liming increased iron content in foliage, and this tendency is stable and keeps over the entire period of our study. Relatively great extent of decrease in the amount of assimilated iron was found at rate of 2,5 t/ha hydrated lime. The manganese is absorbed more intensely in the leaves of white wine varieties, and especially in those of Sauvignon Blanc. The lowest manganese content is found in leaves of Merlot variety. Liming of soil in terms of this field experiment causes a statistically proven increase in the manganese content in foliage of wine grape varieties, included in this study. [ABSTRACT FROM AUTHOR]

Liming increases soil negative charges and thus affects the chemical equilibrium of cations between the solid phase and the soil solution with consequences for the mobility of cations. The effects of lime and potassium chloride (KCl) addition on the vertical movement of potassium (K), calcium (Ca), and magnesium (Mg) were investigated in two Brazilian soils. The experiment was carried out in leaching columns. Treatments included a combination of rates of KCl (0, 50, 100, and 200 mg kg−1 K) and acidity levels (without and with liming). Seven water percolations (400 mL per column) were performed at weekly intervals, totaling an equivalent to 357 mm of rain. Raising the soil pH decreased the leaching of K, in both soils, up to 50% because of the increase of its electrostatic adsorption on created negative charges. Addition of KCl increased the percolation of K, Ca, and Mg proportionally to the rate applied, and it was more efficient than calcium carbonate to percolate Ca in both soils. Liming must be taken into consideration when K leaching or plant needs of K are estimated in predominantly variable-charge soils. [ABSTRACT FROM AUTHOR]

This study compares the effect of lime additions on the spatial variability of Fe, Mn and Zn extracted by Mehlich-1 during three different growth stages from an acid paddy soil, a Typic Plintacualf, in Corrientes, Argentina. Field trials were set up involving three treatments: control, without lime addition, plus two different dolomite doses of 625 and 1250 kg ha. Soil was sampled first before sowing in aerobic conditions and then two more times in anaerobic conditions, i.e. by bunch formation and flowering. Ninety-six samples per plot were taken per lime treatment and sampling period, using a nested sampling strategy. Liming significantly increased extractable Fe and Mn, but decreased extractable Zn. The spatial variability of the studied soil properties was assessed using semivariogram analysis and examination of kriging maps. Models were fitted to experimental semivariograms for 27 data sets, i.e. three different soil properties, each of them sampled in three treatments and during three dates. Soil extractable and Fe, Mn and Zn exhibited a rather strong spatial dependence, as nugget variance was either null or a small proportion of the total variance, and this all over the three different study periods and for the three lime treatments. Geostatistical analysis provided insight into possible processes responsible of the observed spatial variability patterns within the rice soil. Kriging was useful in mapping soil micronutrient variability allowing identifying microrregions with high or low Fe, Mn and Zn concentrations, which showed the presence of small scale variability. These findings indicate the potential for applying the principles of precision agriculture to control spatiotemporal variability in rice fields. [ABSTRACT FROM AUTHOR]

This article aims to compare the effects of applying three doses of sewage sludge, with or without liming, on organic matter, total and available chromium (Cr), and their concentration in plants. Unfertilized (NF) and mineral treatments were used as control. Soil organic-matter (SOM) modification depended on the interaction of liming and sewage sludge implementation. Liming, high sludge doses, and mineral treatment caused less SOM in the second year of study. However, after 3 years, SOM was increased by both mineral and sludge fertilizers compared to NF treatments as result of tree development and the reduction of organic-matter mineralization into the soil. These findings could have important implications for soil carbon storage capacity. Total Cr in soil and forage was increased by sewage sludge application compared to mineral or NF treatments. Liming increased Cr availability in the spring of 2000, where sewage sludge was applied, and reduced Fe availability. [ABSTRACT FROM AUTHOR]

Abstract: Air-drying of soil samples is known to increase the exchangeable fraction of cadmium (Cd) in soil. Liming, on the other hand, reduces bioavailability of heavy metals in soil by metal hydrolysis reactions and/or coprecipitation with carbonate. However, due attention has not been paid to desorption and mobilization of Cd from air-dried and limed soils at realistic ionic strengths. We compared Cd desorption from moist and air-dried samples of two texture-contrasting soils which had been spiked with 3 or 30mg-Cd kg−1 after liming with 25mmolkg−1 of Ca(OH)2, or without prior liming. Repeated batch extraction with water and 1–10mM CaCl2 solutions was carried out, and chemical speciation of dissolved Cd performed using Visual MINTEQ. Desorption of Cd from the exchangeable pool in the soils was not exhaustive, with smaller fractions of Cd remaining after five extractions in the coarse-textured Chiba soil having lower CEC than the fine-textured Takada soil. Air-drying enhanced Cd desorption from the both soils particularly in the first extraction, with the cumulative Cd desorption after five extractions 1.5 times, on average, as large as that from the unlimed moist soils. Liming suppressed the Cd release, resulting in cumulative desorptions 0.14–0.19 times those from the unlimed counterparts. The air-drying and liming effects on Cd desorption were reflected in the apparent Cd2+/Ca2+ exchange selectivity coefficient, which was lowest in the first extraction upon air-drying, and significantly increased upon liming. Alternatively, assuming that constant Cd2+/Ca2+ exchange selectivities obtained from the moist unlimed soils apply, exchangeable Cd pools in the air-dried and limed soils were evaluated. The exchangeable pool was found to increase, on average, by 26% and 30% upon air-drying, and decrease by 79% and 86% upon liming in the Takada and Chiba soils, respectively. These results demonstrate that the size of exchangeable Cd in contaminated soils is prone to change upon drying and liming, and that the potentially desorbable Cd is only slowly mobilized under ionic strength conditions prevailing in the field. [Copyright &y& Elsevier]

Soil acidity is the principal limiting factor in crop production in Oxisols, and deficiency of micronutrients has increased in recent years because of intensive cropping. A field experiment was conducted over three consecutive years to assess response of common bean (Phaseolus vulgaris L.) to lime and iron (Fe) applications on an Oxisol in a no-tillage system. Changes in selected soil chemical properties in the soil profile (0- to 10- and 10- to 20-cm depths) with liming were also determined. Lime rates used were 0, 12, and 24 Mg ha-1, and Fe application rates were 0, 50, 100, 150 200, and 400 kg ha-1. Both lime and Fe were applied as broadcast and incorporated in the soil. Grain yields of common bean were significantly increased with the application of lime. Iron application, however, did not influence bean yield. There were significant changes in soil profile (0- to 10-cm and 10- to 20-cm depths) in pH, calcium (Ca2+), magnesium (Mg2+), hydrogen + aluminum (H+ + Al3+), base saturation, acidity saturation, cation exchange capacity (CEC), Ca2+ saturation, Mg2+ saturation, potassium (K+) saturation, and ratios of Ca/Mg, Ca/K, and Mg/K. These soil chemical properties had significant positive association with common bean grain yield. Averaged across two depths and three crops, common bean produced maximum grain yield at pHw 6.3, Ca2+ 3.8 cmolc kg-1, Mg2+ 1.1 cmolc kg-1, 3.5 H+ + Al3+ cmolc kg-1, acidity saturation 41.8%, CEC 7.5 cmolc kg-1, base saturation 57.4%, Ca saturation 45.2%, Mg saturation 14.2%, K saturation 9.1%, Ca/Mg ratio 3.1, Ca/K ratio 22.6, and Mg/K ratio 6.7. [ABSTRACT FROM AUTHOR]

The castor bean is an oilseed crop of outstanding importance in Brazil and worldwide. Besides the wide application in chemical industry, is important due to its tolerance to drought, making it a viable crop for the semi-arid region of Brazil, where there are few agricultural alternatives. However, this culture is not unique to semi-arid region and is also planted with excellent results in various regions of the country. The study aimed to evaluate the effects of liming and potassium fertilization on the crop of castor bean. The experiment was conducted in a greenhouse in a randomized complete block randomized in a factorial 3 x 2, where the first factor consisted of potassium (0, 30 and 60 kg ha-1) and in the presence or absence lime to raise the base saturation to 60%. It was found that liming in combination with an intermediate dose of K2O (30 kg ha-1) elevates the production of dry mass of the area, however not change the concentration nutrients in the castor bean. [ABSTRACT FROM AUTHOR]

Abstract: The effects of different concentrations of soil cadmium (0, 1, 3, 5, 10, and 20mgkg−1) on growth, structural changes and cadmium cellular localization in leaves of maize plants (Zea mays L.) were investigated in a pot experiment. The results showed that the structural changes observed in maize leaves were not only a response to the Cd-induced stress but also a cellular mechanism to reduce the free Cd+2 in the cytoplasm. However, this mechanism seems to be efficient only up to a Cd concentration in leaves between 27 and 35mgkg−1 for soils without and with liming, respectively. The cellular response varied with both the Cd concentration in soil and liming. For limed soil, Cd was preferentially accumulated in the apoplast while for unlimed soils Cd was more evenly distributed into the cells. The ability of Cd accumulation depended on the leaf tissue considered. The apoplast collenchyma presented the highest Cd concentration followed by the endodermis, perycicle, xylem, and epidermis. On the other hand, symplast Cd accumulated mainly in the endodermis, bundle sheath cells, parenchyma, and phloem. Based on the structural changes and growth reduction, the critical toxic concentration of soil Cd to maize plants is between 5 and 10mgkg−1. [Copyright &y& Elsevier]

Liming materials have been extensively used to immobilize heavy metals. Bacteria, archaea, and fungi are sensitive to heavy metals and play critical roles in soil biogeochemical cycling and crop health. However, the responses of bacteria, archaea, and fungi to liming materials in agricultural soils contaminated with heavy metals are still unclear. A field experiment was conducted to assess the effect of liming on the three microbial domains and the potential influencing factors in maize-planted agricultural soil contaminated with Cd and Pb. Using a high-throughput sequencing method, we found that liming materials enhanced copiotrophic bacteria (Proteobacteria, Gemmatimonadetes, and Bacteroidetes), Bathyarchaeota, and arbuscular fungi (Glomeromycota) but suppressed some oligotrophic bacteria (Chloroflexi) and saprotrophic fungi. Notably, soil-available Cd markedly influenced the community composition of prokaryotes but not that of eukaryotes. Similar edaphic factors were correlated with the relative abundance of dominant bacterial and archaeal taxa but with opposite effects. Furthermore, co-occurrence network analysis revealed that the complexity decreased but the fungal nodes and edges increased after liming, indicating that the microbial community was not highly resilient to environmental stresses and the importance of fungi in community structure was enhanced. Overall, these findings suggest that changes in microorganisms resulting from liming facilitate soil biogeochemical cycles but suppress microbial stability, potentially affecting the sustainable use of agricultural soils contaminated with heavy metals. • Liming material was applied to an agricultural soil with Cd and Pb contamination. • Liming enhanced copiotrophic but suppressed oligotrophic microbes. • Liming affected microbial communities by different mechanisms. • Microbial network complexity decreased but the importance of fungi increased. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we studied the nature and hierarchy of the processes responsible for soil evolution as a function of land use (forest and culture). Albeluvisols were chosen as a pedological model for this study. Iron, manganese, calcium, potassium and trace elements were used as indicators of the soil processes. Their spatial distribution was mapped along tongues of Albeluvisols at a pluri-centimetric scale, using X-ray microfluorescence. In both land use, Fe distribution was shown to be closely related to the soil colour variation along the tongues. Nickel and Cu followed the same distribution. Zinc was almost functioning as Fe with the difference that this element was not lost from the transition zone identified between the bleached tongues and the ochre volumes representative of the illuvial horizon. Under forest, the Fe and Mn redox fronts were closely associated that allows mapping them on the same thin section. Manganese disappeared from the neighbourhood of the iron redox front under agriculture. This was interpreted as a slow down of the iron redox process due to pH increase while Mn redox process was not modified. In addition, under forest, Ca seems totally leached. Liming causes an increase of Ca concentrations in the whole soil profile. This Ca is in an exchangeable form principally located at the interface between white and ochre volumes. We concluded that by liming, Man induced drastic changes in the kinetic of redox process in Albeluvisols over 200 years showing at the same time the extreme rapidity of these processes. [Copyright &y& Elsevier]

Information on the redistribution of applied micronutrients into different fractions as a result of lime application is important to predict plant accumulation of nutrients and to select appropriate chemical extraction procedures for evaluation of micronutrient availability. The present work was carried out to study the influence of liming on the availability and redistribution of zinc (Zn) and copper (Cu) among soil fractions. Additionally, the effect of liming was evaluated on the recovery of these micronutrients by different chemical extractants (Mehlich-1, Mehlich-3, and diethylenetriaminepentaacetate (DTPA), which were correlated with Zn and Cu concentrations in corn (Zea mays L.) plants and soil fractions (exchangeable, organic matter, amorphous iron oxides, and crystalline iron oxides). The results showed that Zn added to soil samples that did not receive lime was retained mainly in the exchangeable and organic matter fractions. The liming resulted in distribution of Zn into iron oxides and as a result decreased the plant accumulation of Zn. Mehlich-3 was the most efficient extractant to predict the plant accumulation of Zn in the acid soils, whereas DTPA was the most efficient in the limed soils. The oxide crystalline fraction was the major fraction responsible for retaining Cu in the soils. However, Cu added to soil was distributed mainly into organic matter. Mehlich-3 was the most suitable extractant for predicting the bioavailability of Cu in limed or unlimed soils. [ABSTRACT FROM AUTHOR]

Denuded landscapes adjacent to big polluters represent an extremely harsh environment for plants due to a unique combination of soil toxicity and physical stress. In a 5-year experiment we tested whether survival and performance of seedlings of Mountain birch ( Betula pubescens ssp. czerepanovii) planted in two barren sites around the nickel–copper smelter at Monchegorsk, northwestern Russia, can be enhanced by physical sheltering and how large the supposed benefits to survival and performance are in relation to liming. Seedling performance was assessed by measuring growth parameters and chlorophyll fluorescence. Physical sheltering was found to be beneficial in some conditions: when soil characteristics were not so harsh as to cause 100% mortality, sheltering increased both survival and performance of birch seedlings. Although the benefits of liming on seedling performance and survival were stronger than the benefits of sheltering, sheltering may still have its uses in restoration when large-scale liming is not applicable, for example, when the ecological side effects of liming are to be avoided. [ABSTRACT FROM AUTHOR]

The emerging technique of DGT (diffusive gradients in thin films) can be used to measure porewater concentrations and remobilization fluxes of trace metals in soils. This study reports the fluxes from soil solids to solutions in a soil contaminated with different levels of cadmium (Cd) at the naturally acidic pH and after CaCO3 treatment. The comparison of labile dissolved Cd, determined by using differential pulse anodic stripping voltammetry, and the concentration obtained by DGT shows that pH has little effect on the complexation of Cd in solution and that the effect of liming is more pronounced on the sorption of Cd to the soil particles. The flux from soil to solution seems to be reduced by 10–50 times following liming from pH 5.6 to 7.0. The final concentrations of labile Cd represent 70–95% of the initial labile concentrations and the Cd fluxes varied from 2.8 to 54 µg cm−2 h−1 at pH = 5.6 and from 0.6 to 5.5 µg cm−2 h−1at pH = 7.0. [ABSTRACT FROM AUTHOR]

The suitability of pH buffer methods that determine lime requirement (L.R.) of acid soils of the eastern region of Botswana has not been determined, and the soil physiochemical properties that influence L.R. are not known. As a result, a number of laboratory pH buffer methods for determining L.R. were evaluated by using acid soils from that region. The methods evaluated were the Yuan double buffer (Yuan–DB) method, Shoemaker, McLean, and Pratt double, and single buffer (SMP–DB and SMP–SB) methods, and the Adams, and Evans single buffer (AE–SB) method. The evaluation was based on the ability of the methods to predict the actual L.R. to pH 6.5 determined by the soil–CaCO3–moist–incubation (SCMI) method. The incubation, physiochemical properties, and L.R. by laboratory pH buffer methods were determined in triplicates. All the pH buffer methods were (P < 0.001) significantly correlated (0.79 < r < 0.94) with the SCMI method. The performance was in the order of Yuan–DB method > SMP–DB method > SMP–SB method > AE–SB. However, the SMP–SB has been recommended for routine analysis of soils of eastern Botswana, because it is simple and rapid. The relationship between SCMI method actual L.R. and the physiochemical properties (0.55 < r < 0.71) reveals that the buffer capacity, organic carbon, exchangeable acidity, and extractable aluminum are the most important soil properties influencing L.R. of soils in eastern Botswana. [ABSTRACT FROM AUTHOR]

Discusses the influence of liming on soil acidification and other processes. Process of acid generation in soils; Effect of soil acidity on nutrient and heavy metal transformation in soils; Amelioration of soil acidity through liming; Interactions among lime, nutrient and heavy metal in soil.

In a trial to test the bioavailability of certain heavy metals from slags, twelve liming materials (including different slags) were applied at three different rates to an Acrisol (sandy loam, pH[SUB(water)] of 5.2 and CEC of 4 cmol[SUBc] kg[SUP-l]) from the South African Eastern Highveld. Two Ca(OH)[SUB2] incubations were done on the specific soil -- one in a soil to solution ratio of 1:1 before the trial and another in a soil to solution ratio of 1:2.5 on the control treatment soil after the trial. The Calcium Carbonate Equivalents in HCl (CCE) and RH-values (Resin Suspension Method) were determined for each lime before the trial. After an incubation period of three months, the pH[SUB(water)] and pH[SUB(KCl)] of each of the four replicates for every treatment was measured. An incubation curve and regression equation was drawn up for each lime using the average pH values. Lime recommendations for each lime to target pH-values of 5.8, 6.8, and 7.8 were modeled using the CCE and RH-values as well as the values from the two Ca(OH)[SUB2] incubations. The soil to solution ratio of 1:2.5 and the RH-value gave a very accurate indication of the lime required for the specified pH targets of 5.8 and 6.8. All the methods underestimated the lime required for the target of 7.8. The CCE value overestimated lime reactivity, especially in the case of courser liming materials. However, the RH-value gave a more accurate indication of the reactivity of the lime, especially through the pH ranges 5.8 to 6.8. [ABSTRACT FROM AUTHOR]

Liming is widely used to ameliorate acidic soils. However, few studies have addressed the effects of different lime application rates on soil microbial communities. Specifically, the effects of liming on fungal communities remain largely unknown. Here, we set up a gradient of increasing lime application rates, 0, 450, 900, 1350, 1800, 2250, 3000, and 3750 kg ha−1, to investigate the effects of lime inputs on soil properties and community diversity and composition of prokaryotes and fungi in paddy soils. Our results showed that the effect of liming on soil pH improvement become insignificant when the application rate exceeded 1800 kg ha−1. Prokaryotic diversity and community composition were both significantly influenced by liming, whereas fungal communities were less responsive. Nonetheless, the promotive effects of liming on soil prokaryotic diversity declined when lime application rates exceeded 900 kg ha−1 (or pH > 6.5). Soil pH was the key factor shaping the prokaryotic community, while pH and SOM were both important in explaining the observed variation in fungal communities. Distinct responses of ammonia oxidizing archaea (AOA) lineages were also observed as pH increased. Our results provide insights into the complex responses of both prokaryotic and fungal communities to lime application in paddy soils, and suggest that the amount of lime applied is also important for maintaining a healthy and sustainable soil environment. • Prokaryotes were more responsive to liming than fungi. • Liming effects on prokaryotes vanished when application rates exceeded 900 kg ha−1. • AOA lineages showed distinct responses to increasing lime inputs. • pH was the key factor shaping the prokaryotic community. • Fungal community diversity and composition were linked to both pH and SOM. [ABSTRACT FROM AUTHOR]

Focuses on a study conducted by researcher C.A. Jones and colleagues to determine the effects of liming on arsenic mobility in copper smelter pond tailings and reprocessed tailings to identify the mechanisms involved. How the study was conducted; The results; In which publication the original study was documented.