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Agronomy biofortification is an important crop management strategy to enhance concentrations of micronutrients in edible portions. The availability of micronutrients for plant uptake is reduced by the high salinity, pH, and lime of soils. Hence, this study aimed to determine the most appropriate time and the best ratio of zinc (Zn) and iron (Fe) consumption during the wheat growth stages in a saline and calcareous soil. The experiment consisted of two factors with four levels; 0, 30, 60, and 120 kg Zn ha−1 as Zn0, Zn1, Zn2, and Zn3 respectively, and 0, 2.5, 5, and 7.5 kg Fe ha−1 as Fe0, Fe1, Fe2, and Fe3 respectively, in a randomized complete block design with four replications. The results showed that the interaction effects of Fe and Zn fertilizers application were significant on the wheat yield indices and concentration of Fe and Zn in wheat shoots and grain. The simultaneous application of 120 kg Zn ha−1 and 5 kg Fe ha−1 caused significant improvement (p < 0.05) in thousand kernel weight (9.1%) and subsequently grain yield (23.4%) compared to the control treatment. The Zn concentration in the wheat shoot during tillering (37.0–58.2 mg Zn kg−1) was higher than the other two growth stages (elongation (29.2–40.8 mg Zn kg−1) and booting (20.0–31.0 mg Zn kg−1)). While the highest Fe concentration in wheat shoots was observed at the stem elongation stage (98.5–268.8 mg Fe kg−1), then the booting stage (91.0–150.8 mg Fe kg−1) and finally the least absorption was at the tillering (80.0–120.0 mg Fe kg−1). Because of the high calcium carbonate, salinity and Zn- deficient soil of the experimental site, the Zn concentration in wheat grain was obtained in a range of 3 to 19 mg kg−1. The results clarified that the fertilizer application of 30 kg Zn ha−1 and 2.5 kg Fe ha−1 can be proportionally and simultaneously increased the concentration of Fe and Zn in wheat grain by 100%. Therefore, the soil application of 30 kg Zn and 2.5 kg Fe per hectare proposed for improvement in quantitative (619 kg ha−1 increase in wheat grain yield) and qualities (100% increase in grain Zn and Fe concentration and 8% increase in thousand kernel weight) indices of wheat yield in calcareous and saline soils. [ABSTRACT FROM AUTHOR]

Robust models based on Artificial Neural Network and simplified linear regression were proposed to predict the Unconfined Compressive Strength (UCS) of Lime Treated Soils (LTS). In total, an experimental database using 1120 test specimens was created. Critical examination of the collected experimental data suggested that there are eight key parameters that govern the attained strength gain. These input parameters are liquid limit, plastic limit, dry unit weight, water content, fine content, lime content, curing temperature and curing time whereas the only output dependent parameter is the UCS. The parameters of the proposed model including weights, biases and transfer functions were successfully converted to an explicit mathematical model relating the UCS with the key input parameters. Based on the results of the statistical evaluation, it was shown that a three-layered Artificial-Neural-Network model with 19 hidden neurons was capable to predict the UCS of (LTS) with a high degree of accuracy that was better than that achieved by the developed regression model. A coupling effect of the input parameters and weights analysis were conducted for the developed Artificial-Neural-Network-model to assess the importance of the key parameters. Analysis of weights of the model showed that curing time was the most significant factor affecting strength gain. [ABSTRACT FROM AUTHOR]

Agricultural productivity is significantly hindered by the limited availability of phosphorus in acidic soils due to the presence of aluminum and iron phosphates. Soil liming is commonly employed to enhance soil fertility. However, modifying the pH might also impact the interactions involving existing soil organic matter, leading to changes in the effective concentrations of competing low-molecular-weight acids (LMWOACs) participating in phosphorus adsorption. This study explored the impacts of citric, oxalic, and malic acids in acidic soils from tea cultivation regions within the Eastern Black Sea. These soils had undergone various levels of liming and were incubated for 15 months to assess their effects on phosphorus (P) adsorption in 7 acidic soils. The experimental sorption data were utilized to calculate the soil Langmuir and Freundlich adsorption parameters. In addition, the influences of organic acids and liming levels on the Freundlich and Langmuir model parameters were subjected to ANOVA analysis. The findings indicated that citric acid demonstrated the highest efficiency in diminishing phosphorus adsorption among the tested organic acids, followed by oxalic and malic acids. Three carboxyl groups (−COOH) in citric acid facilitated the formation of more complexes with adsorbed phosphorus on the soil surface. Furthermore, the 100% LR ratio of liming notably decreased phosphorus adsorption, especially in the lower end of the isotherms. Therefore, it can be concluded that the combination of LMWOACs and liming treatments could be used to overcome P deficiency in acid soils with very high P sorption ability. [ABSTRACT FROM AUTHOR]

Ultramafic soils are characterized by low productivity due to the deficiency of macroelements and high content of Ni, Cr, and Co. Incorporation of ultramafic soils for agricultural and food production involves the use of fertilizers. Therefore, this study aims to find the soil additive that decreases the metallic elements uptake by plant using Brassica napus as an example. In this study, we evaluate the effect of manure (0.5 g N/kg of soil), humic acids (1 g of Rosahumus/1 dm3 H2O; 44% C), KNO3 (0.13 g K/kg of soil), lime (12.5 g/kg of soil), (NH4)2SO4 (0.15 g N/kg of soil), and Ca(H2PO4)2) (0.07 g P/kg of soil) on the phytoavailability of metallic elements. The effect of soil additives on metallic elements uptake by Brassica napus was studied in a pot experiment executed in triplicates. Statistical analysis was applied to compare the effects of additives in ultramafic soil on plant chemical composition relative to control unfertilized ultramafic soil (one-way ANOVA and Kruskal–Wallis test). The study shows that in almost all treatments, metallic elements content (Ni, Cr, Co, Al, Fe, Mn) is higher in roots compared to the aboveground parts of Brassica napus except for (NH4)2SO4, in which the mechanism of Mn accumulation is opposite. The main differences between the treatments are observed for the buffer properties of soil and the accumulation of specific metals by studied plants. The soils with the addition of lime and manure have the highest buffer properties in acidic conditions (4.9-fold and 2.1-fold increase relative to control soil, respectively), whereas the soil with (NH4)2SO4 has the lowest effect (0.8-fold decrease relative to control soil). Also, the addition of manure increases the biomass of aboveground parts of B. napus (3.4-fold increase) and decreases the accumulation of Ni (0.6-fold decrease) compared to plants cultivated in the control soil. On the contrary, the addition of (NH4)2SO4 noticeably increases the accumulation of Ni, Co, Mn, and Al in aboveground parts of B. napus (3.2-fold, 18.2-fold, 11.2-fold, and 1.6-fold, respectively) compared to plant grown in control soil, whereas the humic acids increase the accumulation of Cr in roots (1.6-fold increase). Therefore, this study shows that manure is a promising fertilizer in agricultural practices in ultramafic soil, whereas (NH4)2SO4 and humic acids must not be used in ultramafic areas. [ABSTRACT FROM AUTHOR]

The karst area has become a high-risk area for Cadmium (Cd) exposure. Interestingly, the high levels of Cd in soils do not result in an excessive bioaccumulation of Cd in rice. Carbonate rock dissolution ions (CRIs) could limit the accumulation and translocation of Cd in rice. CRIs can become a major bottleneck in the remediation and management of farmlands in karst areas. However, there is limited research on the effects of CRIs in soils on Cd accumulation in rice. The karst area of lime soil (LS) and the non-karst areas of yellow soil (YS) were collected, and an external Cd was added to conduct rice cultivation experiments. Cd and CRIs (Ca2+, Mg2+, CO32−/HCO3−, and OH−) in the rice–soil system were investigated from the grain-filling to maturity periods. The results showed that CRIs of LS were significantly higher than that of YS in different treatments. CRIs of LS were 2.05 mg·kg−1 for Ca2+, 0.90 mg·kg−1 for Mg2+, and 42.29 mg·kg−1 for CO32− in LS. CRIs could influence DTPA Cd, resulting in DTPA Cd of LS being lower than that of YS. DTPA Cd of YS was one to three times larger than that of YS. Cd content in different parts of rice in YS was higher than that of LS. Cd in rice grains of YS was one to six times larger than that of LS. The uptake of Cd from the soil during Filling III was critical in determining rice Cd accumulation. CRIs in the soil could affect Cd accumulation in rice. Ca2+ and Mg2+ had significant negative effects on Cd accumulation of rice at maturity and filling, respectively. CO32−/HCO3− and OH− had significant negative effects on DTPA Cd in soil. [ABSTRACT FROM AUTHOR]

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Introduction: There is lack of information on the impact of acidity correctives (lime and silicate) and nitrogen (N), phosphorus (P), and potassium (K) fertilizers on the fertility, carbon stocks, carbon stratification, and carbon sequestration potential of paddy soils. To fill this knowledge gap and contribute to knowledge on how the treatments impact the soil ecosystem functions and services, a longterm field experiment was established in 1954 with four treatments and five replicates arranged in a randomized complete block design. Methods: Four treatments with five replicates per treatment were laid out in a randomized complete block design. The treatments included control/untreated (CT), only NPK, silicate-fortified NPK (NPKSi), and lime-fortified NPK (NPKLi). The treatments were applied to paddy soils classified as Fluvaquentic Eutrudepts. Results and discussion: Application of the treatments led to significant increases in soil pH by 0.9, 1.12, and 1.5 pH units in the NPK, NPKLi, and NPKSi-treated soils in 2021, respectively, compared to the initial soil pH. The increase in pH subsequently led to significant reductions in C stratification and C stocks, with reduced rates of C sequestration observed to be more pronounced in the soils treated with lime and silicate-fortified NPK fertilizers (NKPSi and NPKLi). Both NPKSi and NPKLi moderately increased soil fertility. The highest increase in soil fertility was observed in the NPKSi treatment, with an annual growth rate of 0.0160 and a relative change ratio of 128.2% relative to the initial soil fertility index recorded in 1970. A Pearson correlation analysis revealed that soil pH, exchangeable calcium, and available silicate were the soil properties that significantly contributed to the increase in the soil fertility of the treated soils in the rice paddy agroecosystem. Significance: Conclusively, the inclusion of silicate in long-term fertilization is an effective strategy to mitigate soil acidity and increase soil fertility. [ABSTRACT FROM AUTHOR]

AbstractSoil acidity has negative effects on both plants and soil. Furthermore, liming is the most common and effective management practice used to neutralize the acid produced in the soil and the problems associated with soil acidification. The study evaluated whether liming impacts wheat growth, yield, nutritional status basis exchangeable, and their related soil acidity indices. A greenhouse experiment was performed under a completely randomized arrangement, with four lime application rates equivalent to (0, 4.0, 8.0, and 12.0 Mg ha−1). The results showed that all yield components significantly increased with increasing lime addition rate. The grain yield, shoot and root dry weight, and plant and spike height improved quadratically (R2 = 0.909, 0.950, 0.976, 0.902, and 0.891, respectively). Additionally, the lime rate influenced P and Mg concentrations in the shoot, and the concentrations of Cu and Zn. With increasing lime rate, the soil exchangeable Ca and Mg concentrations increased quadratically (R2 = 0.969 and 0.984), while the soil exchangeable K and Al concentrations decreased significantly. The pH of the soil solution increased linearly (R2 = 0.994) with the lime addition rate. Liming significantly reduced the exchangeable Al3+ and Al + H in the soil. Finally, liming improves wheat yield in acid soil by reducing the negative effects of Al and H by increasing soil pH, Ca2+, and Mg2+ concentration, consequently improving root growth and resulting in wheat yield. Liming increased the grain yield by 188.7, 198.2, and 322.8% following the increase of lime rate, if compared to the control. Furthermore, lime enhances plant resilience by raising pH and improving soil nutrient availability and the root system. [ABSTRACT FROM AUTHOR]

Limestone is the most widely used agricultural input for soil acidity correction and calcium (Ca) and magnesium (Mg) fertilization. However, other materials have the potential to fulfill these purposes, such as steel slags, also known as silicates. Silicates have higher solubility than limestone, serving as agents for increase pH in no‐till, in addition to being a source of Ca, Mg, and silicon (Si). This study aimed to compare the effects of surface application of dolomitic lime and calcium magnesium silicate on soil chemical properties, soybean [Glycine max (L.) Merr.] nutritional status, and grain yield under no‐till. The experiment was installed in the northwest Paraná State, Brazil, on a Rhodic Eutrustox. Lime and silicate rates were applied by broadcasting before the sowing of soybean. Silicate treatment increases soil Ca2+, pH, and base saturation up to a depth of 0.10 m. By contrast, liming effects on soil chemistry were restricted to the 0.05 m top layer after 24 months of application. The acidity correction and Ca2+ supply to greater soil depths and the increased leaf Si as a beneficial element provided by silicate treatment contributed to increasing soybean yield in the 2018/2019 and 2019/2020 seasons. Lime application, regardless of the rate, did not improve soybean yield. Waste from the steel industry can be used as acidity correctives and source of Si, Ca, and Mg, improving the agronomic performance of soybean. Core Ideas: Silicate is more efficient in maintaining soil fertility compared to lime.Changes in soil fertility were observed up to a depth of 0.10 m after 24 months.Silicate increases silicon content in soybean leaf.Surface application of silicate increased soybean yield up to 43%.Soybean yield did not improve with lime. [ABSTRACT FROM AUTHOR]

Purpose: Wood ash is an important alternative source of inorganic potassium especially for farmers in areas with acidic soils. Method: The experiment was carried out in two phases. In the first phase, treatments consisted of the application of inorganic fertilizer sources (0 kgha-1, 130.44 kgha-1 of urea, and 300 kgha-1 of NPK of 20:10:10) and wood ash (0 tha-1, 5 tha-1, and 10 tha-1) to garden egg seedlings. In the second phase of the experiment, garden eggfruits were analyzed for nutrient contents. Results: Significant (p≤0.05) fruit yield followed this order: 10 tha-1 of wood ash > control > 5 tha-1 of wood ash. Inorganic fertilizer sources effect on fruit yield followed this sequence:  300 kgha-1 of NPK 20:10:10 > 130.44 kgha-1 of urea > control. The interaction of 10 tha-1 of wood ash and 300 kgha-1 of NPK 20:10:10 produced the highest fruit yield (57 ± 0.50 tha-1). A combined application of 300 kgha-1 of NPK and 5 tha-1 of wood ash showed a greater improvement in vitamin C while an integrated application of 130.44 kgha-1 of urea and 10 tha-1 of wood ash increased vitamin A contents of garden egg. Conclusion: Integration of 10 tha-1 of wood ash and 300 kgha-1 of NPK 20:10:10 positively improved the growth and yield of the garden egg. The addition of a lower rate of wood ash to NPK fertilizer and a higher rate of wood ash to urea significantly improved the nutrient contents of garden eggs. [ABSTRACT FROM AUTHOR]

Soil liming is a crucial strategy to reduce acidity and increase nutrients availability. Lime recommendation for eucalyptus aims to supply the Ca and Mg. Lime might reduce metallic micronutrients content in plants (e.g., Cu, Fe, Mn, and Zn), thereby impairing the nutritional status. Copper and zinc fertilization in eucalyptus plantation is recommended to replace the amount extracted from harvesting plant products. We investigated lime and Cu plus Zn application on (a) biomass production, leaf area, and leaf pigments; and (b) Cu and Zn concentration, accumulation, and distribution in Eucalyptus grandis seedlings. The experiment was conducted with eucalyptus seedlings under Ferralsol in five randomized blocks, in a 3 × 4 factorial scheme, with three lime and four fertilizer rates of Cu and Zn. Plants grown under lime application had increased leaf area and flavonoid content. Lime and Cu plus Zn application improved dry biomass relative to plants grown unlimed and micronutrient supply. Copper plus zinc fertilization improves the nutritional status of eucalyptus, leading to enhance content of Cu, Zn, and chlorophyll, which could prove to be a crucial strategy for increased plant growth and, consequently, boosting biomass production. [ABSTRACT FROM AUTHOR]

High rates of limestone have been increasingly utilized in newly converted areas for grain production in agricultural frontier regions to expedite the short-term correction of soil fertility, leading to compensatory yields. However, there is a lack of information about different doses of lime and gypsum for soils in the Cerrado of Matopiba, especially in the state of Piauí, Brazil. The aim of this study was to evaluate the effects of doses of lime and gypsum in newly converted areas for soybean production in the Cerrado of Southwest Piauí. The study was carried out in the 2019/2020 and 2020/2021 crop years, on yellow Oxisol soil, in a randomized block design and treatments following a 5 × 4 factorial: five lime rates (0, 5, 10, 15, and 20 t ha−1) and four gypsum rates (0, 1, 2 and 4 t ha−1), with four replicates. The standard lime and gypsum rates were 5 t ha−1 and 1 t ha−1, respectively. Soil fertility attributes (0.0–0.2, 0.2–0.4, and 0.4–0.6 m), nutritional status of plants, and soybean yield were measured. The increases in grain yield using a lime rate of 10 t ha−1 were 18% and 12% in the 2019/2020 and 2020/2021 crop years, respectively. High lime rates provide a reduction in the concentrations of P, K, and cationic micronutrients in soil, thereby reducing leaf contents of macro- and micronutrients in soybean plants. Concentrations of Ca, Mg, and S in subsurface layers were raised to proper levels, similar to those recommended for topsoil (0.0–0.2 m). The use of gypsum and lime in newly converted areas for soybean cultivation provides quick improvement in soil chemical conditions and reduction in acidity components. The application of 10 t ha−1 of lime improved the soil chemical environment in the Matopiba region the short time available for chemical reactions to occur, allowing soybean cultivation in newly converted areas of Cerrado into agriculture. [ABSTRACT FROM AUTHOR]

In order to study the effects of soda residue content, particle size, moisture content, and curing age on the unconfined compressive strength (UCS) of soda residue cement lime soil (SRCLS), a 4-factor, 4-level orthogonal experimental design was employed in this study. Different conditions of SRCLS UCS and their impacts were tested and analyzed. The internal microstructure and hydration products of SRCLS were studied using SEM and XRD to explore the strengthening mechanism of SR in SRCLS. The results indicate that as the soda residue content gradually increased, SRCLS UCS initially increased and then decreased, with a maximum increase of up to 67%. With increasing soda residue particle size and moisture content, the UCS of SRCLS gradually decreased. The optimized mix ratio was determined to be soda residue:cement:lime:soil = 3%:3%:6%:100%, with the soda residue dried naturally and an ideal particle size of 0.15 mm. The factors influencing the unconfined compressive strength (UCS) of SRCLS, in order of importance, are curing age, soda residue content, moisture content, and particle size of SR. Among these, curing age and soda residue content have a significant impact on the UCS. An adequate amount of SR can act as a fine aggregate filler, replace lime, promote cement hydration, and enhance chloride ion binding. This improves the grading of SRCLS materials and facilitates the formation of cementitious products from AFm, AFt, and Friedel's salt, resulting in denser and stronger SRCLS materials. The research findings provide a reference for the mix design of SRCLS and the large-scale utilization of waste soda residue. [ABSTRACT FROM AUTHOR]

Using coal gangue as a subgrade filler will produce good benefits, and its application prospects are very broad. It is of great engineering and scientific value to study the improvement method and dynamic characteristics of coal gangue subgrade filler under traffic load. Combining the properties of coal gangue material, fly ash and lime and soil were added to improve the bearing behavior of coal gangue subgrade filler. Then, a compaction test was carried out using the principle of orthogonal experimental design. By analyzing the compaction test results, the optimal proportion of each additive was obtained. A large-scale dynamic triaxial test was carried out with the proportion of each admixture in the maximum dry density group in the compaction test. Based on the dynamic triaxial test results, the effect of confining pressure on the permanent strain was analyzed, the analysis model of permanent deformation and cycle number of traffic loading was proposed, and the correctness of the model was verified. In addition, a modified Hardin–Drnevich model was established, which can describe the dynamic stress–dynamic strain curve of coal gangue subgrade filler under traffic load, and then, the dynamic modulus and damping ratio were analyzed. [ABSTRACT FROM AUTHOR]

Soil acidification is an issue for agriculture that requires effective management, typically in the form of lime (calcium carbonate, CaCO3), application. Mid infrared (MIR) spectroscopy methods offer an alternative to conventional laboratory methods, that may enable cost-effective and improved measurement of soil acidity and responses to liming, including detection of small–scale heterogeneity through the profile. Properties of an acidic soil following lime application were measured using both MIR spectroscopy with Partial Least Squares Regression (MIR-PLSR) and laboratory measurements to (a) compare the ability of each method to detect lime treatment effects on acidic soil, and (b) assess effects of the different treatments on selected soil properties. Soil properties including soil pH (in H2O and CaCl2), Aluminium (Al, exchangeable and extractable), cation exchange capacity (CEC) and organic carbon (OC) were measured at a single field trial receiving lime treatments differing in rate, source and incorporation. Model performance of MIR-PLSR prediction of the soil properties ranged from R2 = 0.582, RMSE = 2.023, RPIQ = 2.921 for Al (extractable) to R2 = 0.881, RMSE = 0.192, RPIQ = 5.729 for OC. MIR-PLSR predictions for pH (in H2O and CaCl2) were R2 = 0.739, RMSE = 0.287, RPIQ = 2.230 and R2 = 0.788, RMSE = 0.311, RPIQ = 1.897 respectively, and could detect a similar treatment effect compared to laboratory measurements. Treatment effects were not detected for MIR-PLSR-predicted values of CEC and both exchangeable and extractable Al. Findings support MIR-PLSR as a method of measuring soil pH to monitor effects of liming treatments on acidic soil to help inform precision agricultural management strategies, but suggests that some nuance and important information about treatment effects of lime on CEC and Al may be lost. Improvements to prediction model performance should be made to realise the full potential of this approach. [ABSTRACT FROM AUTHOR]

Soft clay soil is a concern in geotechnical engineering due to its low strength and high compressibility. Soil improvement with stabilization techniques is an interesting topic in the field of geotechnical engineering and pavements. Nanomaterials and biogeotechnicalbased soil improvement are in high demand, as is the case with the objective of this research which is to determine the effect of the addition of nano lime, nano silica, and chitosan biopolymers to soft clay soil on its mechanical properties. The ratio of additives in this study was taken based on previous research, namely 2% nano lime, 4% nano silica, and 0.1% chitosan biopolymer from shrimp shell waste. Specimen variations consist of initial soil, soil mixed with biopolymers, soil mixed with nanomaterials, and soil mixed with biopolymers and nanomaterials. The mixing method in this study was carried out by mixing the additives according to the percentage of the initial soil dry weight, then water was added to the mixture. Compaction and unconfined compression strength (UCS) tests were conducted on each specimen. The results show that mixing soil with nanomaterials and chitosan provides advantages in mechanical properties. This can be seen from the increase in the UCS value which is up to 11 times that of the initial soil and the increase in the maximum dry density value. Soil stabilization using nanomaterials and chitosan biopolymers has a good impact on the environment. Reducing the ratio of lime in soil stabilization on a project scale can reduce CO2 emissions during production and the use of chitosan biopolymer additives can reduce marine biota waste, especially invertebrates. [ABSTRACT FROM AUTHOR]

Clay soil obtained from the Gwagwalada area of Abuja in the Northern part of Nigeria was obtained and used for this study to determine the suitability of water pH on soil strength for waste containment facilities such as landfills and surface impoundments. Water pH influences the strength and durability of soils employed in these facilities and the potential for chemical reactions that can damage containment barriers. An unconfined compressive strength test was conducted using British Standard Light (BSL) and British Standard Heavy (BSH) compaction at varying water pH (i.e., Acidic, Neutral, and Alkaline water) to see the effect it can have on the life span of the clay as a liner material. High-quality liner materials must meet the minimum unconfined compressive strength requirement of 200 kN/m². According to the test outcomes, when the amount of lime in the soil increased, especially at 4% content, the maximum dry density (MDD) increased to 1.81, 1.78, and 1.71 Mg/m³, and the optimum moisture content (OMC) decreased to 15.0,14.0, 16.0% for BSL compaction similar trend to BSH. The MDD is 1.93,1.83, 1.90 Mg/m³, and OMC is 13.2, 14.0, and 12.4% for BSH compaction for acidic, alkaline, and neutral water, respectively. The unconfined compressive strength (UCS) decreases as moulding water increases. The UCS values meet the 200 kN/m² minimum requirement for soils compacted with acidic and neutral pH water for all compaction efforts. When treated with neutral water, the recommendation of 4% lime addition compacted at BSH for liner material construction at -2%, 0, +2% OMC. It is also recommended that alkaline water is unsuitable for constructing liners because it reduces the strength of treated soil. [ABSTRACT FROM AUTHOR]

Several studies have explored the potential of waste marble powder (WMP) and lime (LM) as solutions for issues associated with clayey soils. While WMP enhances mechanical properties and addresses environmental concerns, LM effectively improves soil characteristics. This research investigates the efficacy of LM and WMP, both individually and in combination, in addressing challenges specific to clayey soils in Bouzaroura El Bouni, Algeria. These soils typically exhibit low load-bearing capacity, poor permeability, and erosion susceptibility. LM demonstrates promise in enhancing soil properties, while WMP not only addresses environmental concerns but also enhances mechanical characteristics, providing a dual benefit. The study utilizes a three-variable experiment employing Response Surface Methodology (RSM) Box-Behnken Design, with variations in clay content (88%-100%), LM treatment (1.5%-9%), and WMP inclusion (1.5%-9%). Statistical analysis, including ANOVA, reveals significant patterns with p-values <5%. Functional relationships between input variables (clay, LM, and WMP) and output variables (cohesion, friction angle, and unconfined compressive strength) are expressed through high determination coefficients (R2 = 99.84%, 77.83%, and 96.78%, respectively). Numerical optimization identifies optimal mixtures with desirability close to one (0.899-0.908), indicating successful achievement of the objective with 88% clay content, 3% LM, and 6% WMP. This study provides valuable insights into optimizing clay soil behavior for environmental sustainability and engineering applications, emphasizing the potential of LM and WMP as strategic additives. [ABSTRACT FROM AUTHOR]

This study aimed to assess the nutritional status of soybean and wheat and the relationship with grain yield and biometric components after lime and phosphogypsum (GY) reapplication. Treatments consisted of two lime application methods, surface liming and incorporated liming, to different levels of base saturation (BS) (44, 70, and 90%), in addition to surface liming to 70% BS associated with a standard dose (70GY1) or double dose (70GY2) of GY. Treatments were applied in 2012 and reapplied in 2016. The results refer to the 2018/2019 soybean season and the 2019 wheat season. Lime + GY treatment increased leaf area, plant height, leaf dry matter, and stem dry matter in soybean but had no effect on specific leaf area (235.4 cm2 g−1), stem diameter (6.08 mm), number of pods per plant (71.7), grain number per plant (165), or thousand grain weight (117 g). Liming to 90% BS reduced leaf manganese contents in both crops and leaf iron content in soybean. GY application improved the calcium status of both crops and the sulfur status of soybean. However, 70GY2 reduced leaf magnesium contents in soybean and wheat. Soil tillage without lime reduced wheat yield by 12% compared with no-till. Soybean yield correlated positively with leaf nitrogen (0.79), leaf phosphorus (0.91), leaf area (0.62), and thousand grain weight (0.65), whereas wheat yield correlated with leaf phosphorus (0.83), calcium (0.75), and sulfur (0.74). For improved soybean and wheat performance, it is preferable to apply lime and GY to the soil surface (70GY1), permanently maintaining no-till practices. [ABSTRACT FROM AUTHOR]

Growing concern over the combustion cost and environment has made road engineers and scientists to explore the possible use of locally available materials for the construction of roads. The present study evaluated the strength and durability characteristics of five sites having locally available silty soils using lime and cement–sand stabilization technique. The test results showed that the cement–sand stabilization technique using 6% cement and 5% local sand resulted in higher strength and durability as compared to lime stabilization. There is also a significant increase in the value of the soaked California bearing ratio (CBR). As unconfined compressive strength (UCS) attained the threshold strength as prescribed by IRC SP 72 2015 for the granular sub-base (GSB) layer, by the use of sand cement stabilization, this technique of stabilization for local silty soils could be used for GSB for low volume road (LVR) construction. As observed from microstructural results which were performed by analysing SEM images, sand cement stabilisation leads to CSH gel and agglomerate formation thereby increasing strength and durability properties. The cost analysis for the replaced stabilized GSB layer showed that using sand–cement stabilization, the estimated cost can be reduced by 56% of the total cost as compared to the conventional method. [ABSTRACT FROM AUTHOR]

The acidic soils of western Newfoundland require liming for successful production of most crops. Locally sourced paper mill waste wood ash (WA) and paper sludge (SL) have potential as cheaper alternatives to limestone (LIME). Two greenhouse experiments evaluated WA and SL as liming and soil conditioning amendments for annual ryegrass (Lolium multiflorum) production. At 55 days after seeding, soil pH in WA (6.2 and 6.3) and wood ash and paper sludge (WASL) (6.0 and 6.3) were not different from that in LIME (6.0 and 6.5) for Experiments 1 and 2, respectively. However, pH in SL was 0.4 and 0.3 points lower than in LIME. Compared to LIME, WA, SL, and WASL produced 31%–52% and 57%–74% greater biomass yield in Experiments 1 and 2, respectively. N uptake was greater in WA (60 and 129 kg N ha−1) and WASL (51 and 97 kg N ha−1) compared to LIME (40 and 85 kg N ha−1), in Experiments 1 and 2, respectively. SL did not differ from LIME in Experiment 1, but reduced N uptake by 57% in Experiment 2. The results show significant potential of WA as an alternative amendment for liming and yield improvement of annual ryegrass grown in NL podzolic soils. However, SL has limited potential due to the risk of increasing N immobilization and residual soil mineral N when growing conditions are limiting. Combining SL with WA or biochar seemed to alleviate these risks. Overall, the adoption of these amendments for field production systems warrants serious consideration, following supplemental field studies to determine optimal application rates and timing. Core Ideas: The podzolic soils of Newfoundland have low pH and fertility, hence require liming.Locally sourced wastes, such as paper mill wood ash (WA) and sludge (SL), could be used as liming and nutrient sources.WA was equivalent to limestone (LIME) in improving and sustaining optimal soil pH.WA produced 52% and 74% greater annual ryegrass yield than conventional LIME application in podzolic soils. [ABSTRACT FROM AUTHOR]

Construction of earth fill dams offers a cost-effective solution for various purposes. However, their susceptibility to internal soil erosion, known as piping, poses a significant risk of structural failure and resultant loss of life and property. Soil stabilization emerges as a practical technique to fortify these dams against such threats. This study investigated the impact of lime on the internal erosion properties of clay soils, focusing on CH and ML soil types. Specimens of different lime content were prepared and remolded at 95% relative compaction and optimum moisture content. Hole Erosion tests at varying lime concentrations and curing durations were adapted to conduct the investigation. This investigation aims to optimize lime content and curing time for cohesive soil stabilization against internal erosion. Findings revealed that 2% and 5% of quicklime, by dry weight of the soil, effectively stabilized CH and ML soils, respectively, against internal erosion, with a two-day curing period proving optimal. Furthermore, the addition of lime significantly enhanced erosion rate index and critical shear strength in clay soil, underscoring its efficacy in soil stabilization efforts. [ABSTRACT FROM AUTHOR]

Expansive soil exhibits significant swellings and shrinkages, which may result in severe damage or the collapse of structures built upon it. Calcium-based admixtures, such as lime, are commonly used to improve this problematic soil. However, traditional chemical additions can increase significant environmental stress. This paper proposes a sustainable solution, namely, the use of lignin fiber (LF) from the paper industry to partially replace lime as an amendment for expansive soils. Both the macroscopic and microscopic characteristics of the lignin fiber-treated expansive soil are extensively studied. The results show that the mechanical properties of expansive soil are improved by using lignin fiber alone. Under the condition of an optimal dosage of 8%, the compressive strength of lignin fiber-modified soil can reach 193 kPa, the shear strength is increased by 40% compared with the untreated soil, and the water conductivity is also improved with the increase in dosage. In addition, compared with 2% lime-modified soil, the compressive strength of 8% lignin fiber- and 2% lime composite-treated expansive soil increased by 50%, the cohesion increased by 12%, and the water conductivity decreased significantly. The microstructure analysis shows that at an 8% lignin fiber content, lignin fibers interweave into a network in the soil, which effectively enhances the strength and stability of the improved soil. Simultaneously, the fibers can form bridges across the adjacent micropores, leading to the merging of pores and transforming fine, dispersed micropores into larger, connected macropores. Lime promotes the flocculation of soil particles, forming larger aggregates and thus resulting in larger pores. The addition of fibers exerts an inhibitory effect on the flocculation reaction in the composite-improved soil. In conclusion, lignin fibers are an effective addition used to partially replace calcium admixture for the treatment of expansive soil, which provides a sustainable and environmentally friendly treatment scheme for reducing industrial waste. [ABSTRACT FROM AUTHOR]

The present study has focused on stabilizing the soils of the embankments and improving the mechanical properties of gravel in subbases of pavements with different contents of bottom ash from thermal power plants and low percentages of lime. The density, humidity, simple resistance strength and bearing capacity of the new materials resulting from this combination have been studied. The results indicated that the optimal proportion of bottom ash added to the analyzed soil is 15%, while the optimal addition of lime is 1% for application in embankments and 2% for application in road subgrades. In clay soil that has a low simple resistance strength when 25% of bottom ash is added without lime, it can double the resistance. In the case of the gravel evaluated, it was found that the optimal ratio between the addition of bottom ash and lime is 6.5. In conclusion, it can be noted that soil that does not have any resistance when certain percentages of bottom ash are added, its properties are improved to be used in embankments. [ABSTRACT FROM AUTHOR]

Enzyme-induced calcite precipitation (EICP) emerges as a highly effective and well-established technique within bio-cementation approaches, offering notable advantages over traditional methods. Conversely, lime, known for its accessibility, cost-effectiveness, and efficacy, serves as a valuable material in enhancing the engineering properties of problematic soils. This study explores the application of EICP and lime treatments separately on two distinct soils (low-plastic and high-plastic soil) exhibiting different mineralogical and plasticity characteristics to assess their impact on strength and swell characteristics. Various combinations of treatments, including jack bean (JICP), soya bean (SICP), and bio-enhancer (BICP), were employed for EICP treatment. Bio-enhancer, rich in natural urea and urease enzyme, was particularly remarkable due to its compatibility with urea supplementation. Similarly, jack bean and soya bean exhibited high efficacy in natural urease enzyme content. The study has revealed that the unconfined compression strength (UCS) of red soil increased significantly by six times at the end of 21 days of the curing period with JICP treatment, while lime treatment was more effective for the black soil. Specifically, the UCS of black cotton soil increased by 11 and 17 times when treated with Enzyme-Induced Calcite Precipitation (EICP) and lime, respectively. Moreover, EICP with J2 solution (jack bean solution with 1M urea and 4 g/L non-fat milk powder) reduced swell pressure by 60% and 67.5% in low-plastic and high-plastic soil, respectively. Lime treatment, on the other hand, led to a swell pressure reduction of 47% and 70% in low-plastic and high-plastic soil, respectively. As a result, EICP proved efficient in mitigating swell pressure for red soil, whereas lime treatment performed exceptionally well for black soil, highlighting the soil-specific effectiveness of each method. Furthermore, a life cycle assessment revealed substantial carbon footprint emission savings with EICP treatment strategy. In brief, this paper contributes to understanding the phenomena and significance of these two treatment techniques on distinct mineralogical soils. [ABSTRACT FROM AUTHOR]

Tillage conservation practices (CA), traditional agriculture (TA), and liming influence soil properties and crop yield. However, it is essential to demonstrate which tillage and liming practices improve soil properties and forage corn yield. This study compared soil properties and forage corn production in two tillage systems with the addition of dolomite and lime, which formed four treatments. The tillage in the first three days surpassed the TA soil CO2 emission, with 64.8% more CO2 than in the CA soil, and the TA hydraulic conductivity and bulk density were more suitable than those in the CA soil. The CA soil had 233 earthworms m−2 more than in TA. The TA green forage corn yielded 6.45 t ha−1 more than in CA, with a higher P, Ca, and Mg foliar content than in CA, but in the CA, the foliar N and K were higher than in TA. The liming increased soil cations (except K), highlighting the lime on dolomite with—52% Al and + 4.85 t ha−1 of forage corn compared to the control. Soil CO2 emission was far lower in CA than in TA, with a slightly lower forage yield, and other soil properties were improved, meaning lower land preparation costs and time savings than in TA. Lime improved acidic soil faster than dolomite, generating higher forage yields. [ABSTRACT FROM AUTHOR]

Background: Soil acidity, low soil nutrient status and low nitrogen fixing inoculants as a result of poor soil fertility management practices are the major constraints in soybean production in Assosa Zone, particularly in Assosa and Bambassi districts. Hence, this experiment was conducted to evaluate the effect of bio-, organic and inorganic NPSB fertilizers and lime on soil physico-chemical properties. Methods: During the period 2019-2020 factorial combinations of two bio-fertilizer inoculants [without bio-fertilizer (B1) and SB12 plus MAR1495 bio-fertilizer at their recommended rates of 500 g ha-1 (B2); two organic fertilizers without fresh cattle manure (M1) and fresh cattle manure at 10 t ha-1 (M2); two lime rates without lime (L1) and lime at 5 t ha-1 (L2); two inorganic NPSB fertilizers NPSB at 9.5-23-3.5-0.05 (F1) and NPSB at 19-46-7-0.1 (F2) at their recommended rates for soybean] were laid out in a randomized complete block design with three replications. Bulk density, pH, total nitrogen, available phosphorus, organic carbon and cation exchange capacity were collected and analyzed using SAS software version 9.1.3 and significant mean differences were separated using Duncan's multiple range test (DMRT). Result: Bulk density, pH, total nitrogen, available phosphorus, organic carbon and cation exchange capacity were highly affected (P<0.01) by the interactions of bio-, organic and inorganic fertilizers and lime. Finally, the interaction of SB12+MAR1495, 10 t/ha fresh cattie manure, 5 t/ha lime and NPSB at 19-46-7-0.1 improved the bulk density, pH, total nitrogen, available phosphorus, organic carbon and cation exchange capacity at both districts. [ABSTRACT FROM AUTHOR]

Lime application combined with complementary sustainable management practices increases crop yields, but liming is only modestly applied in Serbia. This study investigated the influence of liming (1000 kg/ha) combined with the common application of mineral fertilizers on maize yield and the chemical properties of pseudogley soil. The experiment was conducted near Kraljevo, Western Serbia, on the maize hybrid ZP 606 sown in a two-year monoculture. The experiment had three treatments: fertilizer, fertilizer + lime, and a control treatment. The soil is acid, poor in humus, and contains an increased content of mobile aluminum. There was a significant increase in yield under the fertilizer and lime + fertilizer treatments, compared to the control. The yield of maize in the limed treatment was 4.4–9% higher than in the fertilizer treatment. The positive effects of liming on soil are related to an increase in pH, base saturation, and available phosphorus, and a decrease in available aluminum. In the fertilizer treatment, there was a small decrease in pH and base saturation, whereas the amount of aluminum remained high, indicating that the further application of fertilizers without lime can increase aluminum content and foster its toxicity. The long-term sustainability of maize production in Serbia should include liming as a regular management practice on pseudogley soil, with the utilization of smaller doses of lime because of the potential CO2 effects. To improve soil health, food, and environmental security, and to incorporate new crops, developing a framework promoting liming as a sustainable management practice is of high importance. [ABSTRACT FROM AUTHOR]

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]

Expansive soil, also called swelling soil can cause severe damage to buildings and foundations due to the high swell-shrink behavior corresponding to moisture content changes. Slag, which is defined as the by-product of the iron and steel-making process, has been widely used as a stabilizer agent for developing clay soil mechanical characteristics. This review paper highlighted the findings of previous studies on treating expansive soils utilizing several types of slag. The effect of mixing slag with other additives such as Portland cement and lime on expansive soil swelling properties was reviewed. [ABSTRACT FROM AUTHOR]

In Romania 49.5% of the total soil surface have pH below 5.8 which represents a risk for aluminum toxicity and plants growth. Research carried out in the High Pitești Plain aimed to study exchangeable aluminum presence in cultivated soils in order to issue recommendations for acid soils liming. Soil samples collected from the first soil layer, down to 25 cm depth, were analysed in the laboratory and the reaction, humus and available phosphorus and potassium contents, and cation exchange properties were determined. Out of 120 analysed samples 38 showed contents below the method's detection limit. Relationships were drawn for the rest 82 of them between humus and available phosphorus and potassium on one hand and soil reaction and aluminum contents on the other to assess aluminum variability and its possible toxicity for plants. Low, very low, and extremely low aluminum quantities were found which means there is no immediate risk of soil acidification in the studied area from this point of view. Researches must be carried on though in other Romania agricultural land on acid soils. [ABSTRACT FROM AUTHOR]

Fertilization methods have the capacity to modify both soil fertility and biological characteristics, consequently affecting the ecological functions of the soil. Straws are a hard crop residue to decompose, and stimulate the appearance of a specific functional microbiome. The microbial functional profile is correlated with the application of calcium carbonate (CaCO3) and fertilizers containing nitrogen, phosphorus, potassium (NPK). The present study aims to analyze the effect of long-term application of inorganic fertilizers and liming on the functional soil microbial communities. A modified EcoPlate method was used to incorporates the utilization of straw subjected to a 30-day incubation period in the soil at the Livada Agricultural Research and Development Station. In the aftermath of the Ecoplate experiment, discernible alterations in substrate solubilization rates have been noted across diverse soil compositions, spanning from untreated soil to those enriched with nitrogen, phosphorus, and an NPK complex. The results provide information on important functional soil microbial assemblages influenced by fertilizer application and the detection of the most active functional gropus associated with straw decomposition process. [ABSTRACT FROM AUTHOR]

With civilization and urbanization growth, appropriate construction sites with satisfactory geotechnical conditions become less available. Hence, the chemical stabilization of soil has always been an issue of concern for engineers, applied for ground improvement. The present article discusses the influence of metakaolin on the geotechnical properties of sandy soil treated with lime. For this purpose, Proctor and Direct Shear tests were performed to study the mechanical behavior of both untreated and treated soil specimens. The lime in percentages of 3, 6, 9, and 12% by dry weight of sand was utilized, and the metakaolin was added to partially substitute this stabilizer by 10, 20, and 30% of its weight. The results indicated that the inclusion of lime increased the maximum dry unit weight and decreased the optimum moisture content of the soil. While the metakaolin addition slightly augmented the moisture content of the lime-soil mixtures and improved their maximum unit weights at high contents. The research findings showed that for all the stabilizer contents, the shear strength and shear strength parameters of the soil were improved. Yet, the highest improvement was detected when lime was partly replaced by the metakaolin admixture for some contents. The brittleness index of the soil mixtures augmented with the incorporation of lime or L-MK and reduced by increasing the normal stress. [ABSTRACT FROM AUTHOR]

In a rangeland ecosystem, it is important to pay attention to environmental factors and their effect on the distribution and establishment of plants in order to plan exploitation. The purpose of this research is to investigate the relationship between the cover of some species and environmental factors in the north of West Azerbaijan province. For this purpose, in the period from mid-May to the end of June 2021, sampling of vegetation in eight rangelands sites with different vegetation combinations in Chaipareh and Khoy Counties in a systematic-random method with the establishment of transects and plots one square meter was done. Soil samples were taken from each of the sites at five points from 0 to 20 cm depth and taken to the laboratory to measure soil parameters. The results of the use of detrended correspondence analysis (DCA) showed that the importance of the axes based on the specific value decreases from the first axis (eigen value equal to 0.36) to the second (eigen value equal to 0.23) and third axis, and as a result, the major contribution of changes in the distribution of plant species is related to the first and second axis. Changes in species distribution due to soil and topography factors were investigated using the linear redundancy Detrended Analysis (RDA) method. The results of the redundancy analysis showed that the four axes explain a total of 83% of the variance of species composition changes by environmental factors, and therefore this indicates that the investigated parameters have a direct effect on the distribution of species, but because the first axis, it has the highest value (0.295) and is related to different soil parameters, and this indicates that the contribution of soil on the distribution of species in the study sites is more than the topographical parameters. The general results of this study showed that the distribution of rangeland species in the study sites is influenced by soil and topographical factors. It seems that the higher the altitude, organic carbon, saturated moisture, percentage of sand, silt and clay, the slope and direction of the range and calcium in the rangeland site, the more frequent the presence of some species such as Artemisia fragrans Willd, Antemis koteschyana Boiss, L., Cynodon dactylon and Ceratocephalus falcatus L. increases and as the amount of soil cations, electrical conductivity, lime percentage and soil acidity decrease, the abundance of some other species such as Phlomis olivieri Benth, Teucrium polium L., Alyssum minutum Schltdl. and Tanacetum polycephalum Sch.Bip is more common in study sites. [ABSTRACT FROM AUTHOR]

Expansive soils are one of the most problematic soils faced by civil engineers in various construction activities. It has the property to swell with the addition of water and shrink on water removal. The volume change behavior of expansive soil occurs vastly during seasonal changes in moisture conditions and can be significantly attenuated by chemically stabilizing the soil. In this study, calcium lignosulphonate (LS), a biopolymer, is added to the soil to curtail the swelling nature of the soil. Lime (L) is also used to treat the soil, and a comparative study is carried out to examine the effectiveness of LS. The expansive soil is treated with several combinations of cushion layers with 1.5% LS, 2% L, 4% L, and combination of 1.5% LS and 2% lime. To counter the swell pressure of the expansive soil, the treated soil and additive composites are placed as a cushion layer over the expansive soil with the replacement ratio of 1:1 and 1:2, represented as configuration "a" and "b." The swelling pressure of the proposed arrangement is evaluated through the constant volume swell apparatus. The soil layers are inundated from the bottom upwards, and the swell pressure is determined for the various configuration adopted. The effectiveness of the stabilized soil cushion over expansive soil is analyzed through the numerical software PLAXIS 2D for further extension to field conditions. As the replacement thickness of stabilized soil increases, the swell pressure decreases. Nevertheless, the lime-treated soil layer depicted lesser swell than the LS-treated soils. Analyzing the conditions for field situations in numerical analysis yielded consistent results with the laboratory inferences. [ABSTRACT FROM AUTHOR]

Lime is commonly used to neutralize acidic soil in practical farmland management. This study aimed to examine the effect of soil pH change by liming in acidic soil on the mineralization and microbial assimilation of 13C-labelled maize straw-derived hydrophilic and hydrophobic fractions in a 60-d incubation experiment. Our results showed a higher cumulative mineralization of hydrophilic fraction in acidic (34.5%) than neutralized Ferralsol (22.3%), related to lower microbial substrate use efficiency under low soil pH. The cumulative mineralization of hydrophobic fraction was similar between acidic and neutralized Ferralsol. Soil pH affected substrate (hydrophilic and hydrophobic fractions) utilization by actinomycetes and bacteria, but not fungi. The utilization of hydrophilic fraction followed the order: bacteria (57–68%) > actinomycetes (10–19%) > fungi (4.2–5.5%). In contrast, utilization of hydrophobic fraction was the highest for fungi (24–38%), followed by bacteria (21–29%) and actinomycetes (3.2–15%). Actinomycetes showed a greater preference for hydrophilic fraction in neutralized than acidic Ferralsol; bacteria preferred to utilize hydrophilic fraction in both soils, while fungi favored hydrophobic fraction. Also, various substrate uses were found in specific phospholipid fatty acids, which showed that some individual species harbor particular organic C metabolization strategies. In conclusion, soil pH regulates the mineralization of hydrophilic fraction and variously determines the preferential utilization of hydrophilic and hydrophobic fractions by fungi, bacteria, and actinomycetes. Highlights: • Greater mineralization of hydrophilic than hydrophobic fraction was observed in acidic Ferralsol. • The pH sensitivity of substrate utilization followed the order of actinomycetes > bacteria > fungi. • Substrate utilization patterns differed for members of microbial communities. [ABSTRACT FROM AUTHOR]

Results of eleven survey rounds of arable soils performed from 1964 to 2022 in the southwestern part of the central chernozemic region in Belgorod oblast are analyzed. Ordinary chernozems predominate in the steppe zone of the region, and typical and leached chernozems predominate in the forest-steppe zone. During the eleventh survey round (2019–2022), the average application of mineral fertilizers was 114.4 kg a.i./ha; of organic fertilizers, 9.6 t/ha; the rate of liming of acid soils was 43 800 ha per year. As a result, the average yield of winter wheat increased to 5.09 t/ha, sugar beet up to 45.6 t/ha, and corn for grain up to 7.15 t/ha. At the same time, the maximum value of the weighted average content of organic matter (5.3%) was recorded in the soils of cropland for the entire observation period. The part of acid soils decreased to 28.6%, and the part of moderately acid soils decreased to 3.0%. The hydrolytic acidity decreased to 2.7 cmol(c)/kg. The weighted average content of available phosphorus (139 mg/kg) and potassium (161 mg/kg) was the highest in the central chernozemic region. Soils with the low content of available sulfur comprised 85.7% of surveyed soils, those with the low content of zinc, 97.2%; copper, 92.5%; cobalt, 98.8%, manganese, 40.1%; and molybdenum, 21.3%. In terms of the content of available boron, 98.2% of soils were classified as very rich. [ABSTRACT FROM AUTHOR]

The findings revealed that the addition of nanoalginate and lime had distinct effects on various soil properties. Specifically, the liquid limit (LL) and plastic limit (PL) decreased when sodium nanoalginate and lime were added, while the plasticity index (PI) and shrinkage limit (SL) increased. Furthermore, the soil classification was altered when sodium alginate and lime were introduced to the control soil. Regarding the standard Proctor test, it was observed that adding sodium nanoalginate increased the maximum dry density and reduced the optimal moisture content, whereas lime had the opposite effect by decreasing the maximum dry density and increasing the optimal moisture content. The free swelling and swelling pressure tests indicated that the incorporation of sodium nanoalginate and lime reduced both free swelling and swelling pressure. The most significant reduction was observed in the sample containing 7% sodium nanoalginate and 5% lime. Additionally, the study highlighted the influence of processing time, showing that an increase in the curing time led to a decrease in free swelling and swelling pressure in samples mixed with 3% sodium nanoalginate and lime. The XRD test showed that adding sodium nanoalginate reduced primary minerals, forming SAH, while lime reduced quartz and calcite, creating CSH. Overall, the results suggest that sodium nanoalginate can be a more environmentally friendly alternative to lime for soil stabilization projects. [ABSTRACT FROM AUTHOR]

This study was conducted to identify and evaluate some of the fertility characteristics of soils in stream beds in Şebinkarahisar district of the Giresun province of Türkiye, which has a transitional climate between semi-arid and humid climate zones. To this end, a total of 48 soil samples, surface (0-30 cm) and subsurface (30-60/61/62/65 cm), were collected from 24 different sampling points on various stream beds. The textures of the surface and subsurface soils taken were determined as CL, SL, SCL, L, C, and LS. pH values of surface soils ranged from 5.84 to 7.98, and the pH values of subsurface soils ranged from 6.06 to 8.05. Lime contents of the soils without salinity problem ranged from 0.00% to 38.30% for surface soils, and from 0.00% to 37.90% for subsurface soils. Organic matter contents varied between 0.32% and 4.16% for surface soils, and between 0.14% and 2.16% for subsurface soils. While the soils were poor in total nitrogen, phosphorus, zinc and manganese, it was determined that the calcium and copper contents were at sufficient levels. Although deficiencies were detected in some soils for potassium, magnesium and iron, they were generally determined to be at sufficient levels. To deal with deficiencies of macro and micro plant nutrients, including deficiency of organic matter, a fertilization planning is recommended that includes barnyard manure, poultry manure, green manure, compost, vermicompost, and various organic fertilizers containing macro and micro elements. Within the scope of the research, climate classifications were also made according to Thornthwaite, De Martonne-Gottman and Erinç methods by had used 48 years (1965-2012) climate data of Şebinkarahisar district. Plant species and varieties to be grown in the study area should be selected from among those suitable to the transitional climate conditions prevailing in the region. It will also be useful to analyze the stream waters in the areas where soil sampling is done. [ABSTRACT FROM AUTHOR]

This present study investigates the recovery of wood biomass ash (WBA) as chemical stabilize in compacted earth bricks. The specimens were tested for compressive and thermal properties in dry state. The tests were performed at 7 and 28 days of age in order to evaluate the effect of the partial substitution of soil with WBA on the mechanical and thermal properties of the compressed earth bricks. The results indicate that bricks manufactured with 20% of partial substitution showed better performance than those containing only soil. Nevertheless, the use of WBA as source of lime improved the compressive strength and the thermal conductivity of the bricks stabilized with different proportions (5, 10, 15 and 20% wt) when compared with bricks fabricated with 100% soil. This improvement is owing to the pozzolanic reaction produced between the soil components and the WBA as well as the soil microstructure. It was also concluded that the combination of the soil components and lime containing in WBA in the stabilization of compressed earth bricks seems to be a promising alternative when considering issues of energy consumption and pollution. [ABSTRACT FROM AUTHOR]

The current work is directed to study the variation of suction with time and soil water characteristics curve (SWCC) for natural and treated gypseous soil treated with two types of additive (lime and silica fume) compacted at different initial degrees of saturation S0 = 20 and 50 %. Soil subjected to wetting in an upward direction. Three types of gypsum soils were experimented with different gypsum content 15, 35, and 60 % taken from various sites in Salah Al-dean government, Iraq. The main results show that the air-entry value, residual values, and the time required for the entire saturation stage increases with increasing gypsum content and treatment with lime and silica fume and they for soil treated with silica fume are greater than for soil treated with lime. The rate of flow for soil treated with silica fume is less than that of soil treated with lime. The treated soil is more effective in increasing the time required for the entire saturation stage and decreasing the rate of flow when compacted at an effective degree of saturation S0 = 50 %. [ABSTRACT FROM AUTHOR]

This paper reports for the first time the use and application of a novel technique in the characterization of mineral carbonation reaction and CO2 sequestration in soil stabilization using flow meters. Soils based on SiO2 with two different sizes were tested. Lime (Ca(OH)2) was used as the reactant. Instant CO2 flow rate (L/min), total CO2 volume (L), temperature (°C), and absolute pressure (kPa) were monitored and recorded for 1 h by flow meters connected to the mold inlet and outlet. It was determined that the mineral carbonation reaction started in the first seconds and ended before the 5th minute. The mineral carbonation is a short-term and potential reaction, and it is not a time-dependent reaction. It is separated from other carbonation reactions with these characteristics. The highest CO2 captured value was obtained in the soil mixed with 5% lime, where fines were not used. The second highest CO2 captured value was obtained in soil mixed with 1% lime, where fines were not used. CO2 captured with 1% lime is more than CO2 captured with 5% lime in the soil containing fines. Accordingly, 1–5% lime can be used in soil carbonation studies. According to the soil properties, the highest CO2 captured and the CO2 efficiency was achieved with the use of 6–7% water by weight. [ABSTRACT FROM AUTHOR]

Limestone needs to react with water to correct the soil acidity. Therefore, it is expected that soil water availability interferes with limestone reaction time. The objectives of the study were (1) verify whether soil water availability alters limestone reaction time and (2) to evaluate whether the period of less than 60 days between limestone incorporation and sowing is sufficient to correct soil acidity. Two trials were carried out in a greenhouse, in a completely randomized design, in a factorial scheme. In the first trial, the BRS RB331 Ipyporã grass was grown, and the soil was subjected to the combination between the number of times the soil was raised to the maximum water retention capacity (1, 2, 3 and 9 irrigation) and two base saturation (50% and 60%). In the second trial, the Panicum maximum cv. Mombasa was grown, and six treatments were adopted in a 3 × 2 factorial scheme, consisting of the combination of three levels of water availability (50%, 75% and 100% from maximum water-holding capacity) and two limestone reaction periods (30 and 60 days). Soil water availability significantly influenced the limestone reaction time. As a result, it is possible to implant Mombasa and BRS Ipyporã grasses after 30 days of limestone incorporation, provided that the water saturation in the soil is increased to 75%. [ABSTRACT FROM AUTHOR]

Constructing on soft clay entails engineering challenges, such as significant volumetric changes; hence, stabilizing such problematic soil is essential. Since using lime in stabilizing soil is not recommended in some regions (e.g., Manitoba, Canada) due to some environmental concerns, there is a pressing need to explore suitable alternatives. This study investigates the efficiency of stabilizing soft clay using nano-modified cementitious binders (cement, slag, and nano-silica), reinforced with a new class of fibers (basalt fiber pellets). The mechanical and durability properties of the mixtures have been tested in terms of California bearing ratio, unconsolidated–undrained triaxial stresses, and freezing–thawing resistance. Thermogravimetry and scanning electron microscope analyses were performed to interpret the bulk trends. The results showed significant improvement for soft clay specimens stabilized with the nano-modified cementitious binders and reinforced with the pellets. This demonstrates the potential of the proposed reinforced binders for field applications involving the stabilization of soft soils. [ABSTRACT FROM AUTHOR]

Tolga is a 5,200 ha sheep and cropping farm located near Kulin in Western Australia (WA). Since 2004, its production system has been a blend of conventional and alternative practices; some of these alternative practices are common in non-broadacre industries. The alternative practices are based on an understanding of soil health gained from the Australian Soil Planners system which aims to improve the farm's biological functioning and nutrient cycling. This includes use of phase rotations with legume (subclover) pastures tended as a crop, minimal, but necessary synthetic fertilisers and chemicals, supplementary nutritional packages for pastures, animals, and soils, supplementing chemical control with nutrition and grazing management where possible, corrective liming to address soil acidity, and using deep rooted tillage radish to recycle sub soil nutrients, promote root biomass to reduce the impact of soil compaction and possibly, reduce enteric methane emissions. Livestock performance is very high by industry standards, and crop yields, previously similar to district average, are improving in response to a greater proportion of the farm dedicated to livestock / pasture production. The reasons for the high level of livestock performance are not thoroughly understood, emphasising the need for research into the farm's system. Estimated profitability is around the median of a leading consultant's cohort of farmers for that rainfall zone; however, the low variability in its profit is reflective of the top 25% of the cohort, ranked on profit (gross margin) per hectare. The business has steadily grown over the past 30 years. Emissions (T/CO2e/ha) are estimated to be low compared to industry benchmarks and evidence exists that the farm's total organic carbon pool is either reflective of or is as much as 40% higher than the surrounding area. [ABSTRACT FROM AUTHOR]

The soil acidity problem is intensified by improper utilization of synthetic fertilizers in addition to other naturally existing causes; thus, it is important to consider effects on soil health beyond seasonal crop productivity. Most widely used sources of soluble phosphate fertilizers cannot perform effectively on acidic soil due to its fixation. Field experiments were conducted on the acidic nitisols of Welmera District in two locations to determine the effects of using lime and different phosphorus fertilizer sources on the soil acidity attributes and nutrient use efficiency of barley crops. Treatments include a factorial combination of 4 different phosphate fertilizer sources (PARP, MOHP, NPSB, and NAFAKA) with 2 application rates (34.5 kg P2O5 ha−1 and 69 kg P2O5 ha−1) and 2 lime application rates computed from soil exchangeable acidity result 404.25 kg·ha−1 and 563.9 kg·ha−1 for on-station and on-farm sites, respectively, with no lime application (1/4th of LR and 0 lime). Partially acidulated rock phosphate as a phosphorus fertilizer significantly improves soil acidity attributes such as exchangeable acidity, present acid saturation, and plant available phosphorus, and also another soil nutrient status is significantly affected by using different phosphorus sources with the lime application. Application of PARP phosphate sources significantly improves soil exchangeable acidity and present acid saturation by 42% and 41%, respectively, over the commonly used NPSB standard sources of phosphorus fertilizer. Using lime with alternative phosphate sources also contributes to more effective nutrient use efficiency and barely yields improvements with a productive acid soil amendment option. Maintaining soil health by using those integrated approaches improves the efficient utilization of scarce unrenewable resources on sustainable bases. [ABSTRACT FROM AUTHOR]