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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]

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]

Cadmium (Cd) pollution poses a growing threat to rice production in acidic paddies. In south China, a common agricultural practice involves the combined utilization of Chinese milk vetch (M) and rice straw (R). However, it is unclear how the addition of lime to these amendments affects Cd bioavailability and accumulation in soil. Control (CK), chemical fertilizer (F), Chinese milk vetch + rice straw + chemical fertilizer (MRF), and Chinese milk vetch + rice straw + chemical fertilizer + lime (MRFL) treatments were applied to develop a kind of green, efficient, and practical amendment for acidic paddies. We conducted a microplot experiment to explore Cd immobilization in paddy soil and the Cd content in rice grains with these treatments. The results showed that compared with F, the rice Cd in the MRF and MRFL treatments were significantly decreased by 51.7% and 65.2% in early rice and 23.0% and 43.3% in late rice, respectively. Both the MRF and MRFL treatments significantly reduced soil available Cd and weak acid-extractable cadmium (Aci-Cd) concentrations and increased soil organic matter (SOM), exchangeable cation concentrations, and pH, which converted Cd into a stable form in soil. In addition, the MRF and MRFL treatments increased soil pH value by reducing soil exchangeable hydrogen ion concentration (E-H). Additionally, recombination of Cd forms was the primary factor in the reduction in available Cd concentration according to partial least squares path modeling (PLS-PM) analysis. The Cd concentration of rice grains was primarily associated with soil available Cd, soil pH value, and SOM. Overall, these results provide useful data and novel insights into reducing rice grain Cd in south China. [ABSTRACT FROM AUTHOR]

Cropping of acid sulfate soils requires effective treatment of their inherently low pH. We evaluated the efficacy of applications of two levels of lime (0 or 2 Mg/ha), two levels of organic fertiliser (0 or 5 Mg/ha), and three levels of biochar (0, 10 or 30 Mg/ha) in a factorial design for ameliorating acidity in an acid sulfate soil, and measured the subsequent growth and yield of baby corn (Zea mays L.). Lime increased soil pH(H2O) from 3.75 to 4.12, salinity from 1.72 to 1.95 dS/m, and cob yield by 30%. None of the amendments significantly altered total organic carbon or total nitrogen concentrations in the soil. Biochar additions increased cob yields by an average of 28% on both unlimed and limed soil. Addition of organic fertiliser increased cob yield by 45% on unlimed soil but had no significant effect on yields on limed soil. The yields obtained with liming were similar to the highest yields achieved with biochar or organic fertiliser applied either separately or in combinations. Overall, cob yields were increased by 19% with addition of organic fertiliser. The yield increseas from additions of biochar or organic fertiliser were associated with improvements in nutrient supply. However, the increases in cob yield were associated with reduced cob protein, probably resulting from poor availability of nitrogen late in the season. We conclude that biochar and organic fertiliser applied in relatively large quantities can be viable treatments for cropping acid sulfate soils. Biochar and organic fertiliser when applied in relatively large quantities can be as effective as liming for cropping acid sulfate soils. The three amendments added separately or in any combination increased growth and yield of baby corn but impaired cob protein content. [ABSTRACT FROM AUTHOR]

Urea is the most used nitrogen (N) fertilizer worldwide, but its rapid hydrolysis on the soil surface results in N loss in the form of ammonia (NH3-N). Enzyme inhibitors have been investigated for their ability to reduce NH3-N volatilization, particularly from no-till and surface-limed soils. This study assessed the efficiency of stabilized fertilizers in reducing NH3-N volatilization under different lime rates and application methods. The experiment followed a 2 × 4 × 3 factorial design, with two liming methods (surface application and incorporation), four base saturation levels (50, 60, 70, and 90%), and three urea (45% N) sources: conventional urea, urea + N-(n-butyl)-Thiophosphoric triamide (NBPT), and urea + Boron (B) + Copper (Cu). NH3-N volatilization losses varied from 9.15 to 20.43 kg ha−1, accounting for 11.4 to 25.5% of the applied N rate. Base saturation did not influence NH3-N volatilization. Liming method, however, had a significant effect. Urea + B + Cu was effective in reducing volatilization loss only in soils ameliorated by lime incorporation (23% reduction compared with conventional urea). Urea + NBPT was effective in surface-limed and incorporated soils (up to 55.5% reduction). The results showed that soil management influences the efficiency of stabilized fertilizers and that urea + NBPT provides the best results. [ABSTRACT FROM AUTHOR]

Fertilization with suitable amendment in acidic soil is crucial to achieve long-term high crop yield without deteriorating soil health in intensive cropping system. We studied the chemical and biological properties of soil, soybean, and wheat yield after 47 years of long-term fertilization in an acidic Alfisol. Treatments were: unfertilized (control); recommended N dose (N); recommended N and P (NP); recommended N, P and K (NPK); NPK + hand weeding (NPK + HW); NPK + 10 Mg ha−1 farmyard manure (NPK + FYM) and NPK + 0.40 Mg ha−1 lime (NPK + lime). Long-term application of NPK + FYM significantly enhanced the soil cation exchange capacity (CEC), organic carbon, available NPK and microbial functions compared to NPK. Application of NPK + lime increased soil pH, dehydrogenase activity (DHA) and bacterial population by 15.7%, 38.8% and 145% respectively, over NPK. Continuous inorganic-P fertilizer application leads to substantial build-up of available-P in soil. Fertilization of FYM/lime with NPK recorded higher crops yield compared to NPK. Soil DHA, bacterial population and CEC were most influencing factors governing grain yield. Overall, long-term application of NPK with FYM/lime improved soil health and crop yield, but rate of inorganic-P input should be curtailed in an Alfisol. [ABSTRACT FROM AUTHOR]

A field experiment was conducted during Kharif and Summer seasons for two consecutive years of 2016-17 and 2017-18 with rice (Oryza sativa L.) and cowpea (Vigna unguiculata L.), grown in a sequence at Zonal Agricultural Research Station, Mandya on an acid soil to study the effect of biochar, lime and mangala setright on yield, nutrient uptake and fertility status of an acidic soil. Application of biochar along with soil test value based fertilizer (STV) + FYM + ZnSO4 influenced the productivity of rice and cowpea of 104.82 q ha−1 and 2474.77 kg ha−1, respectively and the uptake of nitrogen, phosphorus and potassium by rice (107.72, 28.16 and 69.34 kg ha−1, respectively) and cowpea (68.06, 5.86 and 38.67 kg ha−1, respectively) significantly, which was found on par with application of biochar along with RDF + FYM + ZnSO4. The soil pH (6.01), organic carbon content (5.03 g kg−1) and available nitrogen (340.45 kg ha−1), phosphorus (39.45 kg ha−1) and potassium (166.45 kg ha−1) significantly increased through the integrated use of biochar, FYM, ZnSO4 and fertilizers. Yield and soil properties like soil pH, organic carbon content and available nitrogen, phosphorus and potassium significantly increased with application of lime and mangala setright as compared to farmer's practice. Highest net income and benefit:cost ratio (2.65) was obtained with integration of soil test value based fertilizer application, FYM and biochar. Significant reduction in the productivity of crop and soil fertility was recorded in farmer's practice. [ABSTRACT FROM AUTHOR]

Many agricultural soils are naturally acidic, and agricultural production can acidify soil through processes such as nitrogen (N) fixation by legumes and application of N fertiliser. This means that decisions about mitigation of soil acidity (e.g. through application of lime), crop rotation and N fertiliser application are interdependent. This paper presents a dynamic model to determine jointly the optimal lime application strategies and N application rates in a rainfed cropping system in Western Australia. The model accounts for two crop rotations (with and without a legume break crop), for the acid tolerance of different crop types, and for differences in the acidifying effect of different N fertilisers. Results show that liming is a profitable strategy to treat acidic soils in the study region, but that there are interactions between N and acidity management. Choice of fertiliser affects optimal lime rates substantially, with the use of a more acidifying ammonium-based fertiliser leading to higher lime rates. The optimal liming strategy is also sensitive to inclusion of a legume crop in the rotation, because its fixed N can be less acidifying than fertiliser, and it allows a reduction in fertiliser rates. Higher rainfall zones have greater N leaching, which contributes to a higher optimal rate of lime. We find that injection of lime into the subsoil increases profit. Optimal lime rates in the absence of subsoil incorporation are higher than usual current practice, although the economic gains from increasing rates are small. [ABSTRACT FROM AUTHOR]

The present study on the long-term effect of fertilizers, farmyard manure and lime on changes in soil properties and wheat productivity was carried out at Himchal Pradesh Agricultural University, Palampur (India). The soil was acidic in reaction and classified taxonomically as Typic Hapludalf. Soil samples, collected from two depths viz., 0–0.15 m and 0.15–0.30 m after the harvesting of wheat (2015–2016) were analyzed for different soil properties. Regular use of optimal dose of chemical fertilizers and farmyard manure influenced bulk density, porosity, water holding capacity, saturated hydraulic conductivity, mean weight diameter, pH, organic carbon, cation exchange capacity, available nitrogen, phosphorus, potassium, sulfur, DTPA extractable iron, zinc, copper and manganese, microbial biomass carbon, microbial biomass nitrogen and dehydrogenase activity of soil significantly. Highest grain yield of wheat (30.34 q ha−1) was recorded at 100% NPK + FYM which was at par with 100% NPK + lime (27.89 q ha−1). However, imbalanced use of nutrients affected different soil properties and productivity adversely. [ABSTRACT FROM AUTHOR]

Abstract Growing quantities of biomass ashes are currently produced worldwide due to the increasing consumption of biomass in energy applications. The disposal of biomass ash in landfills is costly and leads to the loss of valuable resources. Biomass ash has important macro-nutrient contents and relevant soil liming capacity, and can be recycled to soils, thus contributing to biomass-to-energy process integration and a sustainable energy production. Although the EU Thematic Strategy for Soil Protection has highlighted the importance of promoting soil amelioration through nutrient recycling and some Member States have already recognised biomass-ash value in a context of circular economy, recycling of this material at the EU level and the potential use of ash-based material in fertilisers is still not properly framed by the EU regulatory framework. Adequate regulation for biomass ash from the energy sector is recognised of most importance as a driving force towards implementation of correct management and valorisation of ash as a raw material. This review provides a discussion on biomass ash properties and related EU regulations, notably the Waste Framework Directive and the Fertilisers Regulation, which are relevant for implementing a strategy for valorisation of biomass ash for soil amelioration purposes. Steps needed to provide the biomass ash with an appropriate end-of-waste and/or by-product status were identified. Key product and process aspects to enable the inclusion of biomass ash in the list of materials that can be used as fertilisers or as ingredients of soil fertilisers in the scope of the revised Fertilisers Regulation were discussed. Quality and safety standards to be harmonised at the EU level, as well as necessary revisions of the risk assessment framework were also discussed here. [ABSTRACT FROM AUTHOR]

Chemical fertilizer application is a common agronomic practice to improve crop productivity and liming is often used to counteract the soil acidification caused by long-term fertilization; however, it is unclear whether liming will counteract the effect of long-term fertilization on soil bacterial community structure and its co-occurrence pattern. Here, we examined the influence of long-term fertilization (NPKS) and liming (L) on soil bacterial community structure and its co-occurrence networks by sequencing 16S rRNA gene amplicons. Our results showed that liming counteracted the influence of long-term fertilization on soil pH, but not on soluble organic carbon (SOC) and electrical conductivity (EC). Long-term fertilization affected the abundance of Acidobacteriia, Deltaproteobacteria and Gammaproteobacteria in the 0–10 cm soil, and that of Deltaproteobacteria, Gammaproteobacteria and Gemmatimonadetes in the 10–20 cm soil; whereas liming affected the abundance of Acidobacteriia, Gammaproteobacteria, and Chloracidobacteria in the 0–10 cm soil and that of Deltaproteobacteria in the 10–20 cm soil. The bacterial community structure in soils with the NPKS-L treatment was different from that with other treatments, and was mainly affected by SOC, EC, and NO 3 − concentration. The link numbers in bacterial co-occurrence networks were decreased by long-term fertilization or liming alone, but were increased by the NPKS-L treatment. Notwithstanding the fact that liming alleviates fertilization-induced soil acidification, this study indicates that liming did not counteract the effect of long-term fertilization on soil bacterial community structure and its co-occurrence pattern, hence cannot recuperate the soil microbial functionality that is changed by long-term fertilization. [ABSTRACT FROM AUTHOR]

Perhaps the most outstanding features of the soil solution are its reaction i.e. whether it is acidic or alkaline or neutral. Acid soils are problematic soils because of the fact that soil acidity is a serious threat to profitable crop production and lime is essential for correlation of acidity as well as of toxic and infertile condition likely to be prevalent in the acid soils. A considerable amount of work is necessary to define the optimum pH range for the principle crops and rotation systems practiced in the state, to measure the yield responses to be expected for the more important soil types and to determine the longevity of the lime response. Adsorbed cations, Hydrogen (H+) and Aluminium (Al3+) are largely responsible for soil acidity. The present study was conducted in the Department of Chemistry, Techno India, Batanagar in the year 2015 to determine the Lime Requirement (LR) of acid soils collected from three soil series of Jamtara district of Jharkhand viz., Kunjabana (I), Bhandarbera and Kunjabana (II). In order to determine the LR, the soils were incubated with different doses of lime (Calcium Carbonate) and the result obtained was in the following order: Kunjabana I>Kunjabana II>Bhandarbera. The lime requirement showed significant correlation with pH (H2O) (r=-0.69), pH (KC1) (r=-0.59), clay content (r=-0.53), organic matter (r=0.65), the product of the increase in pH value due to liming and organic matter (r=0.71), CEC (r=0.63), log CEC (r=0.65), A1KC1 (r=0.71), FeNH4OAc (r=0.65), A1NH4OAC (r=0.59), total potential acidity (r=0.52) and lime potential (r=-0.84). [ABSTRACT FROM AUTHOR]

In paddy soils, plant availability of phosphorus (P) increases during the flooding period due to the reductive dissolution of iron (Fe)-bearing minerals on which P is sorbed. Soil chemical properties are a determining factor of P availability and are subject to change after prolonged paddy rice cultivation. The purpose of this study was to evaluate the effects of long-term application of rice straw compost and slaked lime on changes in soil chemical properties, particularly focusing on the increase in available P under reductive conditions. The rice cultivation experiment was launched in 1926 to clarify the effects of mineral fertilizer (NPK), rice straw compost, and slaked lime application on soil properties. The amount of P solubilized under reductive conditions was evaluated by the difference in the P extracted by the Bray II method with and without reductive treatment of the soil. Continuous application of NPK mineral fertilizer without slaked lime resulted in higher amounts of aluminum extracted by acid ammonium oxalate and P extracted by the Bray II method until the 92nd cropping, while the increase in the proportion of available P under reductive conditions was low. In contrast, the amounts of Fe extracted by acid ammonium oxalate and P solubilized under reductive conditions were higher with increasing application of compost. The application of the compost caused strongly reductive conditions in the soil during the flooding period, and the dissolution of P in the Fe-bound fraction was facilitated. However, excessive application of compost led to the dissolution of high amounts of Fe-bound P, resulting in a loss of Fe and P from the cultivated soil. These results suggest that excessive application of rice straw compost and no application of slaked lime may cause a decrease in available P in paddy soils. [ABSTRACT FROM AUTHOR]

Acidic soils typically suffer from high phosphorus (P) retention, a problem that can be dealt with using greater P fertilization, soil liming, or both. The aim of this work was to examine which of these practices bears the more beneficial result forLolium perenneL. growth. In a pot experiment, five acidic soils were treated as follows: L0P0 (unamended control), L1P0 (liming only), L0P1 (P addition only), and L1P1 (both liming and P addition). We found that P amendment alone was sufficient to increase plant P levels when the initial soil P concentrations were low. Liming without P addition increased plant P satisfactorily only in the high-P soil. We conclude that P addition alone is a better practice than liming alone for improved plant growth conditions in acidic, low-P soils, unless there is relatively high P content in soil, in which case liming alone may be sufficient to increase P availability. [ABSTRACT FROM AUTHOR]

Faba beans (Vicia faba L) are grown in northern Tunisia where annual rainfall approaches 1200 mm and where the soil acidity is the most limiting factor for plant growth. Aluminum (Al) and manganese (Mn) toxicities provide a hostile environment to root growth. To alleviate such a problem, farmers use selected acid-tolerant species. However, crop yields remain far below their optimal levels. Liming, a practice to eliminate acidity, has never been tried in this area before. This research aimed to evaluate the impact of lime and mineral fertilizers on root nodulation, plant uptake and yield of faba beans using a pot experiment. Treatments were combinations of two rates of calcium carbonate with three rates of superphosphate and three rates of potassium sulfate. Liming produced significantly higher number and weight of nodules on roots as well as higher nitrogen, phosphorus, and potassium contents in plant tissue. Liming also increased shoot growth and bean yield. [ABSTRACT FROM AUTHOR]

Manganese (Mn) has the potential to reduce cadmium (Cd) uptake by rice; however, the efficiency depends on its soil availability. Therefore, this study designed a slow-release Mn fertilizer by employing a polyacrylate coating. Pot trials were conducted to study the effects of coated-Mn and uncoated-Mn alone or in combination with lime on the dynamics of soil dissolved-Mn and available Cd, and the transportation of Mn and Cd within rice. The results showed that coated-Mn declined the release of Mn until the 7th day of application; however, it consistently supplied more dissolved-Mn than uncoated-Mn. As a result, coated-Mn induced a greater Cd reduction (45.8%) in brown rice than uncoated-Mn (9.7%). The total Cd of rice and its proportion in brown rice were greatly reduced by coated-Mn, indicating the inhibition of root uptake and interior transport of Cd. Additionally, lime addition prominently increased the soil pH and decreased the CaCl 2 -extractable Cd (90.1–93.9%). However, since lime reduced the soil dissolved-Mn, downregulated the OsHMA3 expression and upregulated the OsNramp5 expression, brown rice Cd was reduced by only 43.0%. The combined addition of lime and coated-Mn alleviated the liming effect on soil Mn and gene expression in roots, thereby reducing brown rice Cd by 71.5%. [Display omitted] • Polymer coated-Mn (CMn) constantly supplied dissolved-Mn during rice growth period. • CMn also improved Mn accumulation in rice tissues, while reduced Cd in brown rice. • CMn along with lime was more effective to reduce Cd in whole plant and brown rice. • CMn alleviated the liming effects on soil available Mn and Cd-related transporters. [ABSTRACT FROM AUTHOR]

Citrus pulp is the pulp and peel waste generated by citrus fruit processing. It can be a pollutant when it is disposed of by burning or dumping, but it is rich in organic carbon (monosaccharides, polysaccharides, pectins, and organic acids), suggesting that it could also be a valuable soil amendment. For the purpose of studying the effects of citrus pulp amendant on soil fertility, a study was carried Out using lysimeters where the soil was amended with different quantities of dried citrus pulp. Soil samples were taken periodically over a period of 2 years to evaluate the evolution of the organic matter and the activity of the microbial biomass. The former was evaluated by calculating the TOC and by extracting and characterizing the humified component. while the latter was evaluated through the calculation of the basal respiration, the C microbial content and some enzymatic activities (alkaline phosphatases, ß-glucosidase, and arylsulphatase). The introduction of citrus pulp brought about an improvement in soil quality which continued for 20 months after the application of the amendant. In particular, there was an increase in the soil organic matter, despite the notable mineralization process which took place in the short-term due to the citrus fruit industry residues. In the medium term, the chemical-spectroscopic characterization of the organic compounds of the soil highlighted a great similarity to the natural humic substances. The improvement in soil quality was also demonstrated by the activity of the microbial biomass, with a large and long-lasting increase in microbial and respired C and the stimulation of enzymatic activity. [ABSTRACT FROM AUTHOR]

Accurately estimating lime requirements (LR) of acidic soils has been a concern since liming practices began. The objectives of this study were to: (i) determine if the Shoemaker-McLean-Pratt (SMP) buffer is accurately predicting the LR of Kansas soils, (ii) calibrate the SMP and Mehlich buffers to accurately estimate the LR of Kansas soils to specific target pH values, and (iii) compare the effectiveness of 60-d incubations vs. field-observed lime response in determining LR. Kansas soils were used to evaluate the current LR according to the SMP buffer and calibrate SMP and Mehlich methods. Slope values (SMP LR vs. 60-d LR) <1 andy intercepts >0 indicated that the SMP either overestimated the LR at low values or underestimated the LR at relatively high LR values compared with 60-d incubations with CaCO3. Calibration of the Mehlich buffer to a target pH of 6.8 provided a better fit than the SMP buffer but the opposite was true at target pHs of 5.5 and 6.0. Titration with 0.022 MCa(OH)2 resulted in a LR (target pH 6.8) 55% less than that measured by the 60-d incubation. Evaluation of the SMP buffer, Mehlich buffer, and Ca(OH)2 titration method on 12 soils indicated that the LR estimated by the Mehlich buffer was not significantly different than the LR from the 60-d incubation. Comparison of the LR from 60-d incubations with field-observed lime response showed that the actual LR in the field was greater than that predicted by the 60-d incubation, which warrants further investigation. [ABSTRACT FROM AUTHOR]

Fine root systems may respond to soil chemical conditions, but contrasting results have been obtained from field studies in non-manipulated forests with distinct soil chemical properties. We investigated biomass, necromass, live/dead ratios, morphology and nutrient concentrations of fine roots (<2 mm) in four mature Norway spruce ( Picea abies [L.] Karst.) stands of south-east Germany, encompassing variations in soil chemical properties and climate. All stands were established on acidic soils (pH (CaCl2) range 2.8–3.8 in the humus layer), two of the four stands had molar ratios in soil solution below 1 and one of the four stands had received a liming treatment 22 years before the study. Soil cores down to 40 cm mineral soil depth were taken in autumn and separated into four fractions: humus layer, 0–10 cm, 10–20 cm and 20–40 cm. We found no indications of negative effects of N availability on fine root properties despite large variations in inorganic N seepage fluxes (4–34 kg N ha−1 yr−1), suggesting that the variation in N deposition between 17 and 26 kg N ha−1 yr−1 does not affect the fine root system of Norway spruce. Fine root biomass was largest in the humus layer and increased with the amount of organic matter stored in the humus layer, indicating that the vertical pattern of fine roots is largely affected by the thickness of this horizon. Only two stands showed significant differences in fine root biomass of the mineral soil which can be explained by differences in soil chemical conditions. The stand with the lowest total biomass had the lowest Ca/Al ratio of 0.1 in seepage, however, Al, Ca, Mg and K concentrations of fine roots were not different among the stands. The Ca/Al ratio in seepage might be a less reliable stress parameter because another stand also had Ca/Al ratios in seepage far below the critical value of 1.0 without any signs of fine root damages. Large differences in the live/dead ratio were positively correlated with the Mn concentration of live fine roots from the mineral soil. This relationship was attributed to faster decay of dead fine roots because Mn is known as an essential element of lignin degrading enzymes. It is questionable if the live/dead ratio can be used as a vitality parameter of fine roots since both longevity of fine roots and decay of root litter may affect this parameter. Morphological properties were different in the humus layer of one stand that was limed in 1983, indicating that a single lime dose of 3–4 Mg ha−1 has a long-lasting effect on fine root architecture of Norway spruce. Almost no differences were found in morphological properties in the mineral soil among the stands, but vertical patterns were apparently different. Two stands with high base saturation in the subsoil showed a vertical decrease in specific root length and specific root tip density whereas the other two stands showed an opposite pattern or no effect. Our results suggest that proliferation of fine roots increased with decreasing base saturation in the subsoil of Norway spruce stands. [ABSTRACT FROM AUTHOR]

A field study was conducted with the objective of determining response of dry bean ( Phaseolus vulgaris L.) to liming and copper (Cu) fertilization applied to an Oxisol. The lime rates used were 0, 12, and 24 Mg ha -1 and Cu rates were 0, 2.5, 5, 10, 20, and 40 kg Cu ha -1 . Liming significantly increased common bean grain yield. Liming also significantly influenced soil chemical properties in the top (0–10 cm) as well as in the sub (10–20 cm) soil layer in favor of higher bean yield. Application of Cu did not influence yield of bean significantly. Average soil chemical properties across two soil layers (0–10 and 10–20 cm) for maximum bean yield were pH 6.4, calcium (Ca), 4.2 cmol c kg -1 , magnesium (Mg) 1.0 cmol c kg -1 , H+Al 3.2 cmol c kg -1 , acidity saturation 40.4%, cation exchange capacity (CEC) 8.9 cmol c kg -1 , base saturation 63.1%, Ca saturation 45.7%, Mg saturation 18.0%, and Potassium (K) saturation 2.9. [ABSTRACT FROM AUTHOR]

In a base-poor northern hardwood stand in Quebec, subjected to high acid deposition, sugar maple (Acer saccharum Marsh.) nutrition, growth, and crown vigor were evaluated 10 years after application of 0–50 t·ha–1 of CaMg(CO3)2 in 1994. One decade after treatment, foliar calcium and magnesium concentrations of sugar maple were still higher for treated than for control trees. The analysis of foliar nutrient indices showed that liming improved the nutrition of nitrogen and calcium, but caused imbalance of phosphorus, potassium, and magnesium. In 2004, crown dieback was much lower for limed trees (0.5%–4.5%) as compared to unlimed trees (23.7%). When compared with crown dieback before treatment, dieback of limed trees generally had decreased by 2004, while dieback of untreated maple trees increased over the 1994–2004 period. In 2004, basal area increment for limed trees was nearly double that of unlimed trees. However, no difference was detectable among trees limed at different rates. Midterm efficacy of liming in this study was demonstrated by the improvement of sugar maple calcium nutrition, crown vigor, and stem growth 10 years following treatment. This confirms the potential of liming to limit damage caused by acid deposition in base-poor and declining northern hardwood stands. [ABSTRACT FROM AUTHOR]