Selected Soil Chemical Properties Research Articles

Effects of Slope Position on Soil Physicochemical Properties of Cultivated Land Use Type in Danka Watershed of Dinsho District, Bale Highland, Oromia, Southeast Ethiopia

Quantify and understand soil nutrient loss under different undulating topography farming bases for site-specific management and targeted fertilizer application rates. The study aimed to assess the effect of slope positions on soil physicochemical properties at the Danka watershed of Dinsho District Bale Highland, Southeastern Ethiopia. Consequent to the reconnaissance survey, soil samples were taken from the cultivated land use type in three replications at three different soil depths (0-0, 20-40, and 40-60 cm) and three slope positions (upper, middle, and lower), analyzed follow standard laboratory procedure and further analyzed using R software 4.1.1 version. The results showed soil physicochemical properties were significantly (P ≤ 0.05) influenced by the interaction between slope positions and soil depth. The results of soil physical properties varied from 1.29 -1.73 g cm-3, 2.47 – 2.74 g cm-3, 47.80 - 36.75%, 10.78 – 15.11%, 12.76 – 18.16%, and 4.06 – 8.16% bulk density, particle density, total porosity, FC, PWP, and AWHC, respectively. Selected soil chemical properties varied from 5.91 - 6.45, 0.64 - 3.20%, 0.04 - 0.25%, 1.14 - 5.60 gm/kg, and 10.24 - 37.24 cmol (+)/kg) soil pH, organic matter, total nitrogen, available phosphorus, and CEC, respectively. The values of exchangeable bases were concentration increased from the upper slope position toward the lower slope position and with increased soil depth. Soil micronutrients were increased with increased slope and decreased with increased soil depth. The lowest slope position had relatively better soil nutrient contents than other slope positions. It is advised that integrated soil fertility management, biophysical soil and water conservation, and slope-based, site-specific fertilizer rating for advance agricultural precision and ensure food security.

Effectiveness of micro-dosing of lime on selected chemical properties of soil in Banja District, North West, Ethiopia

Abstract Soil acidity significantly impacted the agricultural productivity of Ethiopia. Liming has been used as a soil ameliorator, albeit it was not successful due to inadequate availability, high cost, and poor infrastructure for lime transportation to the required agricultural land area. Hence, soil amendment with a minimum amount of lime application is a viable option to improve agricultural productivity sustainably. Therefore, this study aimed to investigate the effectiveness of micro-dosing lime on selected chemical properties of acidic soil in North West, Ethiopia. Three lime application methods and eight treatment approaches were used in the field experiment employing a randomized complete block design with four replications. Independent soil samples were collected before and after liming and analyzed for selected chemical properties. Data were analyzed by analysis of variance using SPSS version 22.0 and SAS 9.3. The application of lime had a significant impact (p < 0.01) on the selected soil chemical properties. Micro-dose application of lime efficiently affected the selected soil chemical properties. The results showed that water pH, available phosphorus, cation exchange capacity, and organic carbon exhibited a considerable increase per kg of applied lime: 2.5 × 10−3, 101.3 × 10−3 (mg kg−1), 160 × 10−3 (Cmol(+) kg−1), and 3 × 10−3%, respectively. Conversely, exchangeable aluminum and exchangeable acidity decreased per kg of applied lime by 7.8 × 10−3 (Cmol(+) kg−1) and 12.2 (Cmol(+) kg−1) × 10−3, respectively. Therefore, the micro-dosing lime application proved to be more effective in influencing these soil properties than other application methods, emphasizing its potential as a valuable soil amendment strategy for small-scale farming.

Determining the Best Rate of Blended NPKSZnB Fertilizer for Optimum Onion Yield and Yield Components in Northwestern Tigray, Ethiopia

Aim: The nutrient content of current fertilizer recommendations is unbalanced and is based on a very general and blanket recommendation for all soil and crop types, and their economic benefit is low. Therefore, this study was initiated to validate the recommendations regarding blended fertilizers applied to the soil and to identify the best fertilizer dose that ensures optimal yield and maximum economic return. Study Hypotheses: significance effect of blended NPKSZnB fertilizer on onion yield and yield components. Study Design: The experiment was designed using a randomized complete block design with three replications and seven treatments. Place and Duration of the study: The field experiment was conducted in the off-season of 2018 and 2019 in Tahtay Koraro (two farmers), and Laelay adyabo (two farmers) districts of in northern Ethiopia. Methodology: Seven treatments with NPKSZnB fertilizer rates (25, 50, 100, 150, 200, 250 and 300 kg·ha-1) were tested under irrigation conditions. Thus, for each plot nitrogen from Urea was applied at a rate of 150 kg ha-1. Surface soil samples were collected before planting onion harvesting at a depth of 0-20 cm to analyze selected soil chemical properties such as pH, extractable electric conductivity (ECe), cation exchange capacity (CEC), total nitrogen (TN), available P and exchangeable bases (K, Mg, Ca, and Na). Results: The application of different doses of NPKSZnB under irrigation conditions had a statistically significant (P < 0.05) impact on onion phenology, yield and yield components. The highest average onion yield (10,329 and 19,196 kg ha-1) was obtained after applying compound fertilizer doses of 200 and 250 kg ha-1 in Teahtay Koraro and Laelay Adyabo districts, respectively. However, the use of NPKSZnB fertilizer at a dose of 100 and 50 kg ha-1 for onion cultivation under irrigated conditions in T/koraro and L/adyabo districts was found to be economically viable. Thus, growers in both districts should use NPKSZnB compound fertilizer at these rates for onion production and productivity. Conclusion: Therefore, farmers in both districts should use NPKSZnB compound fertilizer at these rates for optimum onion production.

Short Term Effect of Vermicompost on Soil Chemical Properties under Maize (Zea mays L.) Field in Northern Ethiopia

Aim: The application of vermicompost (VC) to improve soil chemical properties in area that have low soil fertility status is crucial. Thus, the present study was initiated to determine impact of vermicompost on selected soil physicochemical properties. Study Design: The experiment had 7 treatments arranged in a Randomized Complete Block Design (RCBD) with five replications. Place and Duration of the Study: Hence, a field experiment was carried out in 2018 main cropping season at farmer's field at Adiha village in Kolla Tembien district, Tigray, Ethiopia. Methodology: The treatments were 5 levels of VC (0, 2.5, 5, 7.5 and 10 t ha-1), the recommended rate of N and P (46 N and 46 P2O5 kg ha-1), compost at rate of 10 t ha-1 and control. Surface soil samples were collected before planting and after maize harvesting at a depth of 0-30 cm to analyze selected soil chemical properties such as pH, extractable electric conductivity (ECe), cation exchange capacity (CEC), total nitrogen (TN), available P and exchangeable bases (K, Mg, Ca, and Na). Likewise, vermicompost and compost nutrient contents were also analyzed to know their nutrient composition. Results: Soil analysis results before sowing revealed that most of the soil chemical properties were rated as low. However, vermicompost application significantly (P≤0.05) improved the soil chemical properties. The studied soil chemical properties such as OC (1.33%), TN (0.13%), CEC (17.2 Cmol (+) kg-1), and available P (6 .38 mg kg-1) showed an improvement at VC 10 t ha-1rate as compared to the control which was respectively 0.65%, 0.04%, 7.4 Cmol(+)kg-1 and 2.45 mg kg-1. Conclusion: A significant (P≤0.05) increase in OC, TN and available P was observed with increased vermicompost rate under cultivated land.

Integrated soil fertility management using cocoa bean shells improves soil chemical properties, coconut yield and mitigates environmental pollution

One approach to sustain and intensify coconut production is nutrient cycling through an integrated soil fertility management strategy. This strategy may include transferring crop by-products from one farm commodity to another. One such promising by-products identified is cocoa bean shells (CBS), which is in abundance and could serve as an environmental pollutant at Bamiankor, which is a forest zone and an important area for coconut and cocoa productions, located in the Western region of Ghana. Following this, a 42-month integrated soil fertility management field study was conducted to assess improvements in selected soil chemical properties, coupled with vegetative, and reproductive parameters in a Sri Lankan Green Dwarf (SGD) coconut genotype under various fertilizer treatments. The treatments included: no-fertilizer control (CK), nitrogen-phosphorus-potassium (NPK) fertilizer, cocoa bean shells (CBS), and NPK+CBS, which were arranged in a randomized complete block design (RBCD) in three replications. There were appreciable increases in values of soil pH, total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), and available phosphorus (AP). Values in carbon to nitrogen (C:N) ratio after treatment with CBS, however, were significantly reduced. It was observed that collar girth from palms treated with NPK+CBS were significantly higher compared to other treatments. Similarly, number of leaves, percentage of palm inflorescence, and number of nut-load palm−1 year−1 were all significantly higher under NPK+CBS treated palms compared to the other treatments. In conclusion, CBS in combination with NPK fertilizer is recommended as a good strategy to intensify coconut production. However, for a long-term benefit, circularity, cleaner, and sustainable production, addition of sole CBS is advocated. Adoption of this management strategy will also potentially mitigate the negative environmental consequences associated with accumulation of CBS in studied area.

Effects of rice husk biochar charred at different time on soil chemical properties, rice growth and yield

Sustainable rice production in Sub-Saharan Africa especially in Nigeria faces serious constraints due to soil infertility. Recycling of rice residues through biochar production and applying it to the soil could be a possible approach to address the soil fertility constraints facing rice production. A pot experiment was conducted at Imo State University to investigate the effect of rice husk biochar on some selected soil chemical properties, growth and yield of rice. Four treatments evaluated in the pot experiment include rice husk biochar charred at 250oC for 60, 90 and 120 minutes together with control (no amendment). The treatments were replicated three times and laid out in completely randomized design (CRD). The soils in the pots were both treated with basal dose NPK (15:15:15) at 200kgha-1 while biochar was applied at the rate of 10tha-1 to the amendment soils. Application of biochar in this experiment appreciably increased the soil pH, available phosphorus, OC, TN, exchangeable cations, CEC and available silicon in biochar treated pots compare to control pots. The degree of soil improvement was proportional to the charring time. The rice husk charred for 120 minutes (RHB120) showed the highest effect on most of the soil chemical properties evaluated. Biochar amendment was found not to have much influence on the rice agronomical parameters except grain weight in which the highest value was found in soil treated with RHB120 (12.5gpot-1). Therefore, converting rice husk to biochar and applying it to the soil can improve soil fertility status and yield of rice in Nigeria. Keywords: Rice Husk Biochar, Soil Chemical Properties, Rice Growth, Rice Yield

The Impact of Tree Species on Microbial Community Structure and Soil Function on Forest Plantations in the Central Hardwoods Region (CHR)

Interactions between above- and below-ground monoculture forest plantation components are critical to tree growth and development. Within the Central Hardwoods Region (CHR), synergistic relationships between tree species and soil microbial community structure and function have received limited research attention. Soil microbes are integral to forest ecosystems as their activities intrinsically promote soil organic matter decomposition, nutrient cycling, and ecosystem functioning. Here, we examined soils from two perfectly aligned stands of black walnut (BW, Juglans nigra L.) and Northern red oak (RO, Quercus rubra L.) trees. Measurements of selected soil chemical properties, microbial community structure using ester-linked fatty acid methyl ester (EL-FAME), and soil enzyme activities (EAs) were used. Analysis of modifications within microbial communities showed a significant positive response to BW based upon soil EAs and microbial indicators, compared to RO. Seasonal comparisons predictably revealed higher microbial activities during summer. Fungi dominated the soil microbial community structure with a fungal/bacterial ratio of 2:1. Gram-positive rather than Gram-negative bacteria or actinomycetes dominated the bacterial community. The activity of the soil enzymes ß-glucosidase and arylsulfatase increased, but ß-glucosaminidase and acid phosphatase decreased. Additionally, acid phosphatase and arbuscular mycorrhizal fungi revealed strong correlations. The differences observed in biological properties, specifically microbial communities and EAs, highlight the varied responses to BW and RO soil biology and subsequent soil ecosystem functions. These results indicate that variations in microbial abundance and soil functions occur throughout the course of an entire year.

Evaluation of the Effect of Deep Compost Application in the Areas around Vineyard Tree Trunks on Selected Soil Chemical Properties and the Vegetative Growth of the Vine

In the context of sustainability, viticulture will address issues related to soil fertility in the coming period. Greater attention will therefore be paid to replacing traditional manure-based fertilisers, such as farmyard manure, with new types of fertiliser in the form of composts, digestate, etc. Experience to date suggests that good-quality composts are not only a source of nutrients that the vines take from the soil each year, but also a source of organic matter. The application of compost and its subsequent decomposition in the soil profile can have a positive effect on the growth of the roots and above-ground parts of the vine. However, optimising the effects and action of compost is linked to determining the necessary doses and methods of application. The aim of this three-year study was to provide an overview of the results aimed at evaluating the effects of the application of compost (CO) and compost enriched with the addition of lignohumate (CO+L20), at a rate of 30 t·ha−1, in the areas around vineyard tree trunks on selected soil chemical properties and the vegetative growth of the vine (Vitis vinifera L.). The unfertilised variant (CWC) was used as a control. Each variant was established in three replicates that were 20 m long. Experimental measurements and evaluation were carried out in the period of 2018–2020 on two sites with different soil conditions (Lednice and Velké Bílovice) and two different grape varieties (Sauvignon Blanc and Pinot Gris). Meteorological data were continuously monitored during the period under review. Chemical properties of the soil samples of the three experimental variants were determined (e.g., content of organic carbon, humic acids, humic substances, humification rate, etc.). The evaluations that were carried out confirmed that the addition of organic matter in the form of composts to the soil in the CO and CO+L20 variants positively influenced the quality of organic matter. The organic carbon content increased by 56–139% in variants with deep compost application (CO, CO+L20) during the monitored period compared to the CWC, depending on the location. Similarly, the degree of humification increased by 70–84%, and the soil microbial biomass increased by 38–136% in the treated variants compared to the CWC. In addition to the dynamics of the changes in the chemical properties, the aim of the performed measurements was to evaluate the rate of the growth shoots, which was linked to the fertilizing effects of the applied compost in the experimental vineyard. At the site in Velké Bílovice, the total difference in the length of the shoots was higher in the CO by 2.6–4.6% and in the CO+L20 by 7.5–12.5% compared to the CWC. At the site in Lednice, the situation was similar, and the total difference in the length of the shoots was higher in the CO by 4.6–7.2% and in the CO+L20 by 5.3–13.2%. The results that were obtained may constitute an important basis for the management of organic fertilization on plots with different soil conditions and cultivated varieties in order to optimize the vegetative growth of the vine.

Co-Composted Chicken Litter Biochar Increases Soil Nutrient Availability and Yield of Oryza sativa L.

Intensified cultivation of rice has accelerated weathering of most tropical acid soils leading to significant loss of base cations. In most developing countries, rice yield is low and this results in its production being costly because productivity versus labor is low. The objectives of this study were to (i) enhance soil chemical properties, nutrient uptake, and grain yield of rice grown on a mineral tropical acid soil using agro-wastes; (ii) determine the agro-waste (chicken manure, cow dung, forest litter, and Leucaena) that has the potential to significantly increase rice yield; and (iii) determine the residual effects of the organic soil amendments produced from the agro-wastes on soil and rice productivity. The treatments used in this three-cycle field study were (i) soil without amendments (S0); (ii) prevailing recommended rates for fertilizers (NPK-Mg); (iii) biochar–forest litter compost (OSA1); (iv) biochar–chicken litter compost (OSA2); (v) biochar–cow dung compost (OSA3); (vi) biochar–Leucaena compost (OSA4); and (vii) biochar–Leucaena–chicken litter compost (OSA5). Standard procedures were used to determine the plants’ rice growth, grain yield, plant nutrient concentrations and uptake, and selected soil chemical properties. The use of organic soil amendments (OSA1 to OSA5) significantly improved the soil chemical properties, rice plant growth, nutrient uptake, and grain yield compared with the prevailing method of cultivating rice (NPK-Mg). The application of organic soil amendments reduced the use of inorganic N, P, K, MgO, and trace elements fertilizers up to 25%, 100%, 64%, 100%, and 100%, respectively. The organic soil amendments with Leucaena significantly increased rice grain yield of OSA5 at 11.17, 13.11, and 10.06 t ha−1 in the first, second, and third cropping cycles, respectively. The residual effect of the organic soil amendments also improved rice plant growth, nutrient uptake, and rice grain yield although these were slightly reduced as compared to those of the two previous cropping cycles, the afore-stated treatments were superior to the prevailing method of cultivating rice (NPK-Mg). Transforming agro-wastes into organic soil amendments can improve tropical mineral acid soils and rice productivity.

Assessment of the spatial variability of selected soil chemical properties using geostatistical analysis in the north-western highlands of Ethiopia

ABSTRACT The aim of this research was to evaluate the status of selected soil chemical properties and to explore their spatial variability in various agroecosystems (AEs) of Choke Mountain, northwestern highlands of Ethiopia. A total of 74 geo-referenced composite surface (0-30 cm) soil samples were collected from representative farm lands. Soil chemical properties were analyzed following standard procedures. In addition, semi-variogram model was applied to estimate the spatial variability of soil properties. The results showed that soil chemical properties are below their threshold values in all agroecosystems and soil groups. The value of soil pH ranged from 4.3 to 6.8; Exchangeable acidity ranged from 0.124 to 0.180 cmol (+) kg−1; EC ranged from 0.02 to 0.19 dS m−1; OC ranged from 0.7 to 3.8%; TN ranged from 0.11 to 0.27%; Exchangeable potassium from 0.29 to 2.0 cmol (+) kg−1and CEC from 22 to 56 cmol (+)kg−1. The results also revealed that soil pH, exchangeable acidity, electrical conductivity, and exchangeable potassium showed strong spatial dependence whereas SOC and TN had moderate spatial dependence. The results indicated that soil quality is deteriorating. Hence, crop, soil and site-specific soil management strategies, primarily focusing on improving the content of SOM and addressing the problems of soil acidity are suggested to improve the soil conditions.

Evaluation of Micro-Dosing Lime Application on Selected Soil Chemical Properties and Faba Bean Crop Performance in Acid Soil Prone Areas of Central Ethiopia

High cost of lime has precluded their use by smallholder farmers to reclaim soil acidity in Ethiopia particularly in the study area

Effect of Different Nitrogen Percentage Input On Soil Fertility, Plant Nutrients and Yield of Organic Spinach (Amaranthus Spp.)

Nitrogen (N) management is important to assess the N effect on soil and plant under the organic farming system. With this in mind, a glasshouse experiment was conducted to determine the effect of various N inputs on selected soil chemical properties, nutrient content and yield of spinach (Amaranthus spp). The experimental treatments were focused on the different percentages of N input (2, 4 and 6% of N from organic sources) with soil alone as a control. The treatments were applied 14 days after seeding (14-DAS) at a recommended rate of 2 t/ha. The study result found that 4-6% of N input (with T3 and T4) had improved selected soil parameters such as pH, CEC, total N, available-P and exchangeable-Ca. Further, total N content in spinach (cultivated organically), as well as spinach yield, were significant. Study findings have shown that within 4% to 6% of N input promotes soil quality, total nutrients in spinach (leafy vegetables), and can be scaled up to farm level to sustain organic system productivity.
 Vol. 9, No. 2, August 2022: 135-144

Short-Term Effects of Tillage Systems, Fertilization, and Cropping Patterns on Soil Chemical Properties and Maize Yields in a Loamy Sand Soil in Southern Mozambique

Sub-Saharan Africa (SSA) agriculture is characterized by dependence on erratic rainfall, inadequate conservation practices, and a decline in soil fertility resulting in low crop productivity. Therefore, conservation agriculture (CA) has been proposed as an alternative to improve soil fertility and productivity. Hence the aim was to investigate the effects of tillage systems, fertilization, and cropping patterns on selected soil chemical properties (pH, organic carbon, total nitrogen, extractable phosphorus, exchangeable cations, and cation exchange capacity) and identify which cropping pattern maximizes stover and grain maize–legume productivity and land use. A two-year (2016/17–2017/18) field experiment in a loamy sand soil was conducted at Nhacoongo Research Station, southern Mozambique. Two tillage systems (conservation (CA) and conventional tillage (CT)), two fertilization treatments (fertilized and unfertilized), and seven cropping patterns (four sole crops and three maize–legume intercrops) were evaluated in a randomized complete block design with split–split plot arrangement and replicated four times. CA practices resulted in significantly higher soil chemical properties and increased stover and grain yields as compared to CT practices, but fertilization demonstrated insignificant effects on soil chemical properties and significant influences on stover and grain yield of maize and legumes. Cropping patterns induced no significant effect on soil chemical properties and either stover or grain yield. Estimated indices like land equivalent ratio (1.18–2.67) and competitive ratio index (0.01–1.72) confirmed the advantage of intercropping against sole cropping. This is largely supported by the estimated values of aggressivity and relative crowding coefficient. Smallholder farmers can therefore benefit by adopting CA.

The Improvement of Selected Soil Chemical Properties Using Singapore Daisy Based Compost in Ultisols

The Improvement of Selected Soil Chemical Properties Using Singapore Daisy Based Compost in Ultisols

The Improvement of Selected Soil Chemical Properties Using Singapore Daisy Based Compost in Ultisols

The Improvement of Selected Soil Chemical Properties Using Singapore Daisy Based Compost in Ultisols

Exploring the distribution of soil properties across an open-grazed pastoral system in Laikipia rangelands, Kenya

Laikipia rangelands in Kenya are among the most productive ecosystems but there is concern that the traditional free grazing regimes may accelerate soil and vegetation deterioration. We investigated the distribution of soil properties in the rangelands of Ilmotiok ranch in Laikipia County where grazing is predominantly open or free and examined selected soil chemical properties and particle size distribution in three types of habitats (tree, grass and bare ground) along four transects, placed diagonally across hillslope positions. We focused our study on the hypotheses that habitat types and hillslope position had an effect on soil properties distribution along the profile. Along each identified transect, soil samples were collected at four depths 0–10, 10–20, 20–30 and 30–40 cm. Distribution of soil properties mainly carbon, total nitrogen and phosphorus were influenced by hillslope position and habitat type and their contents decreased gradually with soil depth. Soil organic carbon content was high in tree habitats while in grass habitats average total phosphorus content in the profiles was slightly lower than in tree habitats. Total soil nitrogen was highest in the footslope in the tree and grass habitat and ranged between 0.81−2.17 g/kg and 1.26−2.50 g/kg, respectively. Sand was the dominant grain size fraction which accounted for 50−88%. This study demonstrated that there are soil fertility differences in the rangelands caused by vegetation cover and hillslope positions which are particularly important for future agro-pastoral use decisions.

Effect of Coffee Husk Compost and NPSB Fertilizers on Selected Soil Chemical Properties of Potato Field in Chora District, South West Ethiopia

Field experiment was conducted in Chora District of south western Ethiopia, to evaluate the effect of different rates of coffee husk compost (CHC) and 18.9N + 37.7P + 6.94S + 0.15B (NPSB) in the form of NH4, P2O5, SO4−, and B2O5, repectively, blended fertilizer on selected soil chemical properties of potato field during 2021. The treatment consisted of four rates of CHC (0, 2.5, 5, and 7.5 t ha−1) and four rates of blended NPSB fertilizer (0, 112.5, 150, and 187.5 kg ha−1). The experiment was laid out in randomized complete block design with three replications. Postharvest soil data were collected and subjected to ANOVA using SAS version 9.4. All the soil parameters analyzed were significantly (P<0.05) affected by the main factors of CHC and NPSB blended fertilizer except exchangeable K+ and Na+ which were affected by main factors but not by factors interaction. The maximum pH (5.3), OC (6.0%), and CEC (14.10 meq 100g−1) were obtained from application of sole 7.5.t CHC ha−1 which is at par with combined 7.5.t CHC and 112.5 kg NPSB ha−1, while the maximum TN (26%), Av. P (3.57%), and Av. S (4.36%) were obtained from combined application of 7.5.t CHC and 112.5 kg NPSB ha−1. The sole application of either of 150 kg or 187.5 kg NPSB ha−1 was resulted in high exchangeable acidity. Therefore, combined application of CHC and NPSB fertilizers raised the pH, improves the OC%, total N, available P and S, reduced the exchangeable acidity, and raises the CEC and exchangeable bases of potato field soil as compared to the control and sole NPSB fertilizer.

Effect of Applying Low Rates of Agricultural Lime and Chicken Manure on Selected Soil Properties on <i>Ferralsols</i> of Lake Victoria Agro-Ecological Zone, Uganda

Ferralsols form a dominant type of soil on which most crops are grown in the Lake Victoria agro-ecological zone. Soil acidity has been recognized among the most important agricultural problems in such soils, which adversely affect crop production and productivity. A study was conducted with the objective of determining the effect of applying low rates of lime and chicken manure on selected soil chemical properties. Using a Split Plot Factorial Randomized Complete Block Design, agricultural lime (0.0, 0.5, 1.0, 1.5 & 2.0 t·ha-1) as the main plot and chicken manure (0.0, 1.0, 2.0 & 3.0 t·ha-1) as sub-plot were applied, replicated three times. The test crop was common bean var. NABE 15. The experiment was conducted for three rainy seasons, two seasons on-station and one season on-farm on Ferralsol soil in the Lake Victoria crescent of central Uganda. The results showed that applying low rates of lime with chicken manure significantly (p 2 = 0.987) relationship with pH change was obtained when 0.5 t·ha-1 lime was applied with the four chicken manure rates in Mukono. From the study, we recommend the application of small quantities of lime at 1.0 t·ha-1 with either 2.0 or 3.0 t·ha-1 chicken manure.

Agronomic Performance of Barley as Affected by Biochar and Lime Application on Acid Soil of Hula Hagereselam Sidama, Ethiopia

Biochar has been shown to improve soil chemical parameters such as pH, electrical conductivity (EC), cation exchangeable capacity (CEC), and exchangeable acidity, and currently, researchers are looking at its liming potential. In view of this, a field experiment was conducted to assess the main and interaction effects of biochar and lime on yield, and yield components of barley as well as selected soil chemical properties, and to determine optimum combination of soil amendment. A randomized complete block design (RCBD) with three replications was used to lay out a factorial combination of three levels of lime (0, 24.3, and 47.9 t ha^-1) and four levels of biochar (0, 5, 10, and 15 t ha^-1) with twelve treatments combinations. Over the unfertilized plot, the pooled mean analysis revealed that soil amendments had a substantial impact on yield and yield components as well as soil chemical properties. The combined application of 5 t ha^-1 biochar and 24.3 t ha^-1 lime t ha^-1 resulted in the maximum grain yield of barley. The use of 24.3 t ha^-1 lime and 5 t ha^-1 biochar could significantly boost barley grain yields. Therefore, for barley production in the study area and acid soil amelioration, combined use of lime and biochar at rates of 24.3 t ha^-1 and 5 t ha^-1 could be proposed.

Effect of lime on selected soil chemical properties, maize (Zea mays L.) yield and determination of rate and method of its application in Northwestern Ethiopia

Soil acidity is the major soil chemical constraint that limits agricultural productivity in the highlands of Ethiopia receiving high rainfall. This study was conducted to evaluate the effect of different lime rates determined through different lime rate determination methods on selected soil chemical properties and yield of maize (Zea mays L.) on acidic Nitisols of Mecha district, Amhara Region, Ethiopia. The experiment had 10 treatments (0, 0.06, 0.12, 0.18, 1, 2, 3.5, 4, 7 and 14 tons ha−1 lime) that were calculated by three lime rate determination methods and applied through three lime application methods (spot, drill and broadcast). The experiment was arranged in randomized complete block design (RCBD) with four replications. N at the rate of 180 kg ha−1 and P at the rate of138 P2O5 kg ha−1 were applied to all plots. A full dose of P and lime as a treatment were applied at planting; whereas N was applied in split, 1/2 at planting and 1/2 at knee height stage. One composite soil sample before planting from experimental site and again one composite sample from each experimental unit were taken after harvest to analyze soil chemical parameters following appropriate laboratory procedure. Liming showed a positive significant difference on pH-H2O, pH-buffer, cation exchange capacity (CEC) and exchangeable bases but it had an inverse and significant effect on exchangeable acidity (EA). However, it didn't show any significant difference on soil C and N. Grain and above-ground biomass of maize yields had significant differences among treatments. The highest grain and biomass yields (7719 and 18180.6 kg ha−1, respectively) were obtained from application of broad cast method while the lowest (6479 and 15004.6 kg ha−1, respectively) were obtained from control treatment. Drill lime application method provided better efficiency with over 200% cost reduction advantage compared to the broadcast method to ameliorate the same level of acidity. Application of 3.5 tons ha−1 lime in the drilling method is recommendable to ameliorate soil acidity. However, from an economic point of view, application of 0.12 tons ha−1 lime applied in the micro-dosing method is more profitable due to low variable cost.