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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]

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]

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]

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]

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]

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]

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]