Showing papers in "Journal of Soil Science and Environmental Management in 2020"

Validation of blended NPSB fertilizer rates on yield, yield components of Teff [Eragrostis tef (Zuccagni) Trotter] at vertisols of Hatsebo, Central Tigray, Ethiopia

Abstract: Application of unbalanced nutrition was the main yield limiting factor in the study area. Hence, an experiment was conducted during the 2017 cropping season on farmers’ fields to validate and determine optimum blended fertilizer rate for teff production. Eight levels of NPSB (0, 25, 50, 100, 150, 200, 250 and 300 kg ha-1) and recommended NP (100 kg ha-1 urea and 100 kg ha-1TSP) were used as treatments and set in randomized complete block design with three replications. All the fertilizers were applied at planting but nitrogen was top dressed in two time split. Surface soil samples was collected before teff sowing and after harvest; with total nitrogen, available phosphorus, extractable sulfur and boron found to be at low level. Application of different blended NPSB fertilizer rates significantly affected crop phonology, yield and yield components of teff. Highest mean teff grain yield (2803.09 kg ha-1) was obtained in response to 250 kg ha-1NPSB with 62.5 and 33.4% yield increment over the control and recommended NP. Similarly, the highest straw yield was also obtained from plot treated with that rate and it has 80 and 44.4% yield increment over the control and the recommended NP, respectively. The partial budget analysis also revealed that marginal rate of return was highest (1179.5%) at a rate of 250 kg ha-1NPSB+46 kg N ha-1 from which better biomass and economic advantage was attained. Hence it could be concluded that it is possible for optimum teff yield to be attained using 250 kg ha-1NPSB+46 kg N ha-1. Key words: Eragrostis tef, blended fertilizer, yield components, NP fertilizer, Laelay Maichew.

Optimization of the analytical method for the determination of organic matter

Abstract: Soil organic matter represents the remains of roots, plant materials, dead organisms in varies stages of decomposition and synthesis and is variable in composition. Walkley-Black method for the determination of organic matter is the most common method; however, it requires a lot of reagents and chemicals including potassium dichromate which is toxic especially when it is in a hexavalent form. It is very important to be able to reduce the amount of chemicals used during the analysis of organic carbon and it is also very important to reduce environmental pollution since the chemicals released to the environment becomes toxic. As the weight of sample decreases from 1 g (a Walkley-Black recommendation) proportionally with volume of reagents, there is no significant difference shown on the value of organic matter. Using orthophosphuric acid during organic matter determination did not have an impact on the results; however, it helps to observe a sharp endpoint. When the volume of diphenylamine indicator reduces from 15 to 4 drops, the result of organic matter has no significant difference. Key words: Organic matter, optimization, analytical method, Walkley-Black, potassium dichromate.

Effects of long term sugarcane production on soils physicochemical properties at Finchaa sugar Estate

Abstract: In Ethiopia, where sugarcane has been cultivated for over 20 years, changes in soil physicochemical properties are expected to occur albeit information on the extent of change is scanty. A study was conducted in 2015 at Finchaa Sugar Estate with the objective of assessing the status of selected soil properties under long term mechanized sugarcane cultivation. Disturbed composite and undisturbed soil samples from 0-30 and 30-60 cm layers of selected Luvisols and Vertisols at Finchaa were collected for laboratory analysis of selected soil properties. The result of the study indicated that clay content of the land under sugarcane was higher than that of the adjacent uncultivated land use types. The bulk density values for a clay texture for most of the studied soils were higher than the critical values recommended for successful sugarcane production. The pH of the two land uses also ranged from 5.35 to 6.63. Organic carbon (0.95 to 1.32%), total nitrogen (< 0.12%), and available P (2.51-8.63 mg kg-1) were also in the range of those not adequate for sugarcane cultivation. Overall, the measured soil properties indicated that the management practices the estate has been implementing were not adequate to sustain sugarcane production on a profitable basis and, thus, require revisiting the practices. To maintain sustainability of sugarcane production in the estate; soil management practices that can increase soil organic carbon, pH, total nitrogen and soil available P should be employed. Key words: Sugarcane, soil physical property, soil chemical property.

Effects of lime and phosphorous application on chemical properties of soil, dry matter yield, and phosphorus concentration of barley (Hordeum vulgare) grown on Nitosols of Emdibir, Southern Ethiopia

Abstract: The effects of lime and P fertilizer application on chemical properties of acid soil, and dry matter yield (DMY) and phosphorus concentration of barley were investigated in a greenhouse experiment in 2013. The experimental soil was collected from Emdibir, South-Western Ethiopia. Five lime levels (CaCO3) (0, 6093, 12186, 18280, and 24373 mg CaCO3 kg-1 soil) in a factorial combination with five phosphorus (TSP) rates (0, 300, 600, 900 and 1600 mg kg-1) were used. The treatments were replicated three times. Barley, variety HB-1307, was used as a test crop. All the soil and plant analysis was conducted following standard laboratory procedures. The soil chemical properties, except Mg, were significantly (P≤0.05) affected by increasing rates of lime and/or P addition. The highest lime rate resulted in an increase in soil pH, exchangeable Ca and Cu, and a decrease in the levels of exchangeable acidity and Al, Fe, Mn, and Zn. The DMY and plant P of barley were increased with the lime rate. The lime and P interaction effects were significant (P≤0.05) on exchangeable Ca, Al, and DMY. Optimum lime (12186 mg kg-1) application has a decreasing effect on P fixation by Fe and Al. While the optimum lime rate in combination with the highest rate of P enhanced fixation by Ca. The change in soil chemical properties and DMY might encourage better barley growth on this soil. In conclusion, lime application beyond 18280 mg CaCO3 kg-1 soil may not be beneficial for the soil chemical properties and barley DMY. Key words: Chemical properties, dry matter yield, soil exchangeable acidity, phosphorus concentration phosphorus fixation.

Shea waste slurry as an organic soil amendment of tropical soils in the Tamale Metropolis, Northern Ghana

Abstract: Infertile and less productive soil due to continuous cropping, poor soil management and other forms of land exploitation are mostly amended using inorganic fertiliser. Shea waste slurry (SWS) as an organic soil amendment material was applied to soils in two locations and its effect on plant primary and secondary nutrients evaluated. One-way diagonal method was employed in sampling soil from fields measuring 25 m×40 m at depths of 0-30 and 30-60 cm for SWS applied and non-applied soils. Results showed increased pH resulting from SWS application and EC increasing from 41.15±3.89 to 155.5±83.4 µS/cm in both locations. SWS application also increased %N levels at depth of 0-30 cm from 0.03±0.0 to 0.56±0.2%, concentration of P increased from 3.47±0.62 to 262.0±176 mg/kg and K from 21.9±2.39 to 231.6±98 mg/kg. Na levels increased from a low of 0.46±0.09 to a maximum of 2.81±1.0 meq/100 g in both study sites, Mg increased from 0.80±0.3 to 8.51±4.86 meq/100 g whilst Ca increased from 1.6±0.07 to 6.3±098 meq/100 g for the depth of 0-30 cm. Soil %OM and OC, respectively increased from 0.58±0.01 to 10.94±3.95 and 0.34±0.11 to 6.36 ±2.29% for the depth of 0 to 30 cm in both study locations. The study indicated a general increase in the levels of all the parameters analysed for the study at the SWS applied soils as compared to the non-applied soils. The use of SWS as a soil nutrient amendment in crop production as an organic material was observed to be very effective. Key words: Shea waste slurry (SWS), organic soil amendment, tropical soil, plant nutrients.

Use of charcoal (biochar) to enhance tropical soil fertility: A case of Masako in Democratic Republic of Congo

Abstract: Soil fertility transience in the region of Masako in Democratic Republic (RD) of Congo remains a major challenge to sustainable agricultural production. Recently, biochar application as soil amendment has attracted attention of the people across the world owing to its potential to improve soil physicochemical properties, crop yield and carbon sequestration into the soil. A study was conducted in Masako to analyze the use of charcoal (biochar) as soil amendment and assess its effects on soil chemical performance and some biophysical parameters of maize crop. The experiment was set up using randomized complete block design with three replications of three treatments comprising ½ kg of sieved (small-sized particulate) charcoal per m2 (C1), 1 kg of sieved charcoal per m2 (C2) and control group without charcoal (C0). Data were subjected to analysis of variance, Pearson’s phenotypic correlation and regression analyses using genstat 12th edition. The results of the analysis of variance showed non-significant variation for most physicochemical properties of soil and maize phenotypic traits, indicating that treatments had the same effects on soil composition suggesting that there was no clear impact of charcoal amendment as applied except for phosphorus content and collar diameter of the maize crop which were significantly (P ≤ 0.047 and P ≤ 0.043 respectively) influenced by the treatments. The results indicated that biochar improved the soil phosphorus availability by up to 72% as accounted for by the linear contribution of the treatment C2 indicating that biochar could be recommended for use in soil with low level of phosphorous. Key words: Charcoal, tropical soil fertility, Democratic Republic of Congo, Zea mays.

Assessment of selected soil physicochemical properties on different land-use systems and landscape positions at Hamesa watershed, Wolayita zone, Southern Ethiopia

Abstract: The investigation was undertaken at Hamesa watershed of Wolayita Zone with the aim to assess the consequences of land-use systems and topography on the physical and chemical properties of selected soils. Surface soil samples taken at 0-15 and 15-30 cm depths from three land-use systems (enset, grassland and maize fields) were collected under three slope positions (upper, middle and lower). Both the clay and bulk density increased with depth, while total nitrogen (N), OC, available P and micro-nutrients (Fe, Zn, Mn, and Cu) decreased. On the landscape positions, increase in exchangeable Ca and K, pH, bulk density and available Mn down the slope was observed; whereas total N, OC, available P and available Fe showed decreasing trend down the slope. At 0-15 cm soil depth, grassland soils exhibited higher bulk density and lower porosity as a result of livestock movement which was compacted. Grasslands had higher OC and TN compared to the other two land-use systems, due to the accumulation of humus in the root system in the grassland. Application of household refuses and manure contribute to increasing available P, TN, Zn, Ca and K contents in enset farmland. On the contrary, maize land use had lower CEC, K, PBS, Mg, TN and OC, which might be due to crop removal, erosion phenomena, and excessive tillage activities. These results suggest that for sustainable crop production, proper management practices should be in place by considering different slope positions and land-use systems. Key words: Land use system, slope position, physical, chemical soil properties.

Soil moisture retention and rainfed wheat yield variations by the addition of gypsum and green manure

Abstract: In rainfed tract, the success of agriculture depends on conservation and efficient use of soil moisture and nutrients availability that directly linked with the presence of moisture in soil. The moisture can be conserved through several means including green manures and gypsum addition. The experiment was conducted to investigate the integrated effect of green manures and gypsum for moisture conservation and their impact on wheat production under rainfed conditions. The experiment was planned at six sites with five treatments including gypsum at 1 t ha-1, green manure (Guar 40 days old) and gypsum+green manuring were compared with control (untreated) and farmer practice (traditional). Results showed a significant increase (up to 38 to 76%) in wheat grain yield with the application of gypsum and green manure while soil moisture contents were enhanced up to 34 to 65% compared to control. It was also noticed that the treatments altered the soil properties (pH, Electrical conductivity (Ece), Organic Matter, Available Phosphorous and Extractable Potash) positively by improving soil water relationship over the control. Key words: Gypsum, green manure, moisture contents, soil properties, conservation, wheat yield.

Effect of rhizobial inoculation combined with phosphorus fertilizer on nitrogen accumulation, growth and yield of soybean in Benin

Abstract: The objective of this study was to determine the amount of phosphorus application needed for the Bradyrhizobium inoculation to improve soybean N uptake and grain yield. Two factors were investigated: inoculation with Bradyrhizobium diazoefficiens strain USDA 110 and application of phosphorus fertilizer with different doses (0; 50; 100 and 150 kg ha-1 P2O5). Trials were carried out in two agro-ecological zones (ZAE) in Benin with two experimental sites namely Ketou and Ze. The experimental design was a Complete Randomized Block Design. Results showed that the highest mean height values were recorded T1+150P (42.22 cm at Ze and 43.82 cm at Ketou) while the lowest values were recorded with the treatment T0 + 0P. Treatment T0 +100P gave the highest aboveground biomass at 10 weeks after sowing at Ketou (2521.43 kg DM ha-1) while T1+150P recorded the highest aboveground biomass at Ze (3392.75 kg DM ha-1). At Ketou, the grain yield was increased under T1+100P by 98% compared with T0+0P. At Ze, the treatments T1+100P significantly increased the soybean grain yield by 147% compared with T0+0P. Likewise, T1+100P allowed to have the highest total nitrogen yields in the grain which is respectively 144.13 kg ha-1 N and 295.02 ha-1 kg N at Ketou and Ze. Overall, the inoculation with B. diazoefficiens had significantly increased the number of nodules for all of the phosphorus fertilizer amounts. The mycorhization frequency was significantly lower under the treatment T0 + 0P (41.46%) than the other treatments while that was higher under the treatment T1+50P (76.04%). Keywords: Bradyrhizobium diazoefficiens, soybean inoculation, grain yield, Benin.

Soil conservation techniques among arable crop farmers in Odo Otin local government area, Osun state: A multinomial logit approach

Abstract: The study investigated the soil conservation techniques among the arable farmers in Odo Otin local government area of Osun State. Two-stage sampling procedure was employed for the study. Primary data were collected from 120 arable crop farmers in the Local Government Area. Data collected were analysed using descriptive statistics; multinomial logit regression model. Result shows that most the respondents were aware of various soil conservation and mulching/cover cropping were prominent. The result further shows that farm size is positively significant in mulching/cover cropping and shifting cultivation/bush fallowing influenced soil conservation techniques adoption. The study recommends improved conservation technology initiative aimed at enabling local farmers to adopt technology conducive to increasing income as well as to enhancing soil conservation. Also, local institutions should be strengthened and their members empowered such that they can run effective institutions and promote technology adoption at the local level themselves. Key words: Awareness, arable crop farmers, soil conservation techniques, multinomial logit model.

Effect of biochar application on selected soil properties in Southwestern Nigeria

Abstract: This study investigated the effect of biochar on dispersible clay and soil chemical properties. The treatments consisted of four rates of milled biochar (0, 450, 900 and 1344 kg/ha) arranged in a Completely Randomized Design with four replicates. Surface (0-15 cm depth) soil of Iwo (Sandy loam) and Egbeda (Loamy sand) soil series were collected from the Teaching and Research Farm, Obafemi Awolowo University, Ile-Ife, Nigeria. 1 kg of each soil sample was thoroughly mixed with milled biochar at different rate and maintained at field moisture capacity for a period of 12 weeks in the screen house. Soil particle size distribution, bulk density, dispersible clay, soil pH, soil organic carbon and available phosphorous were determined. Data obtained were subjected to analysis of variance; Duncan’s New Multiple Range Test was used to separate significant means at p ≤ 0.05. It was revealed from the results that biochar addition at rate 450 and 1344 kg/ha appeared to be more beneficial and adequately improved soil pH, organic carbon and available phosphorous. Biochar at 900 kg/ha significantly reduced dispersible clay. It was concluded that short term biochar amendment did not improve soil quality of loamy sand. Keywords: Biochar, dispersible clay, soil organic carbon, available phosphorus, soil pH.

Compost biomass, pH value and C, N, K contents of some local wild plant species: Case of Panicum maximum L., Trypsa- cum laxum L. and Pueraria javanica (Benth.) Benth, in the Region of Kisangani, Democratic Republic of Congo

Abstract: Soil fertility transience and weed management are often among decried impediments undermining agricultural productivity in many tropical countries. A study aiming at transforming baffling problems of abundant weed biomasses especially that of Panicum maximum (T1), Tryps-acum laxum (T2) and Pueraria javanica (T3), often cause of crop yield loss into advantage to enhance soil fertility, increase crop productivity as well as help tackle weed issue was initiated in the region of Kisangani. To do this, a 90-day composting experiment involving a mono factorial randomized complete block design including three replications and three treatments of above mentioned weed biomasses was conducted from 23rd March to 23rdJune 2013. The results of analysis of variance showed significant differences among treatments for pH H2O (p≤0.013) and potassium content (p≤0.001). The three composts demonstrated high nutrient content level in total organic carbon, nitrogen and potassium able to restore soil fertility. Moreover, the study revealed that the pH values of all the composts were closer to neutral on average and can be used to fix the recurrent issue of soil acidity in the region. Finally, the results showed that the species were able to produce sufficient compost mass with 41.5, 36.3 and 30.9% of initial mass loss respectively for T1, T2 andT3 in a relatively short time. Key words: Soil fertility transience, compost, weed management, agricultural productivity, DR Congo.

Economic importance of termites and integrated soil and water conservation for the rehabilitation of termite-degraded lands and termite management in Ethiopia

Abstract: In Ethiopia, termites pose serious threat to a variety of agricultural crops, forestry, rangelands, houses and other wooden structures. Termite problem is particularly prevalent in the western part of the country, where it has persisted for many years and has received wide publicity. Termites appeared in the region for the first time in 1904 at a specific place called Bafano Koreche around Kiltu Kara town in West Wallaga zone. From there, they spread in different directions to other areas and termite problem has increased from time to time. The severity of termite destruction has become worse than ever in all the four zones western Oromia National Regional State (ONRS). Termites are also causing serious damages to pastureland in the semi-arid areas of Borna and Guji zones of southern ONRS threatening livestock production. By damaging crops, termites cause food insecurity and by damaging natural vegetation they cause denudation, accelerated erosion, and loss of biodiversity. Therefore, the purpose of this paper is to examine the economic and environmental destruction termites pose in the rural areas of ONRS. Finally, the paper made concrete recommendations to government policy makers and land use professionals in their effort to mitigate the challenges. Key words: Integrated management, soil erosion, termite pest, western Ethiopia.

Organic carbon sequestration in mineral soil layers of cold-temperate mixed forests

Abstract: The aim of this study is to analyze the concentration of soil organic carbon (SOC) and C stocks in cold-temperate mixed forests in southern Quebec, Canada. More specifically, the analysis deals with SOC concentrations and C stocks with respect to other key soil properties and environmental factors (such as soil pH, nitrogen, texture, structure, bulk density, litter thickness, drainage), including vegetation data (such as stems density, tree diameter and basal area). There are a total of 68 sampling sites across the various study sectors, including the collection of 109 soil mineral samples. The results indicate that SOC concentration and soil C stocks are high on average, ranging from 3.31 ±1.49 to 5.88 ±3.95% (SOC) and 70 to 114 t ha-1 C stocks, respectively. The results of the Principal Component Analysis (PCA) reveals that the texture of soils is the variable with the greatest differentiation among the sites, as well as soil acidity, nitrogen, litter thickness and topography. According to the multiple linear regression analysis, the two variables that result from the model are soil acidity (pH) and sand (%), which account for 33.2% of C stock variance. Key words: Soil Organic Carbon (SOC), C stocks, soil properties, environmental factors.

Modifications induced in soil physicochemical properties by repeated fire for different fuel load treatment in a West African savanna-woodland

Abstract: Fire is known to stimulate growth of savanna vegetation, promote species’ diversity, and regulate tree and grass balance. However, the timing and frequency at which savannas are burned and the fuel properties can affect residual soil nutrient content and, ultimately, productivity. The objective of this study is to characterize changes in soil physical and chemical properties in a savanna-woodland subject to different fuel load treatments of burning. To characterize the soil physical and chemical variables, particle size distribution, total carbon, pH, phosphorous content and nitrogen were analyzed for three different soil layers. The results indicated no difference in soil texture between the different topsoil profiles before and after the burning event. Further, there was greater nutrient enrichment of the upper soil layer (p=0.014) due to ash deposition. The spatial patterns of soil temperature during the studied experimental fires could affect soil properties, resulting in new spatial pattern of soil nutrients. The findings of the present study have practical implications for savanna management. The current implementation of prescribed early fires should be continued with due consideration of the burning and fuel properties to avoid detrimental effects of intense fire on soil layers. Key words: Early fire, fire behavior, fire temperature, soil properties, Savanna ecosystem.

Effect of flooding on peatland in U Minh Thuong National Park, Vietnam

Abstract: U Minh Thuong National Park is one of the two significant areas of peatland swamp forest remaining in Vietnam, and is recognized as one of the three highest priority sites for wetland conservation in Mekong Delta. A large area of Melaleuca Forest in the park was destroyed and degraded by a devastating fire in 2002. Besides this, an artificial flooding technique for controlling fire applied all over the park for several years changed the natural development of Melaleuca Forest. As the natural condition of the forest has changed, water management (artificial flooding) needs to be implemented to save this situation. Flooding regime has changed the structure and composition of the peatland, making it to be loose and reduced in structure. The peatland area in the park has water level of 30 cm underground and occupies 15% of the total park area. It emits very large amount of CO2 emissions. The main objective of this work is to study how to protect the forest biodiversity from fire by controlling its water level optimally after rainy season and to study the chemical and physical characteristics of the peatland soil of the forest that affect its water level Key words: Melaleuca Forest, peatland, flooding,

Comparison of several lime requirement methods in luvisol of Southern Ethiopia

Abstract: Ethiopian soil affected by strong acidity accounts for about 28% of the entire country and 43% of the total cultivated land. Soil acidity is expanding in scope and magnitude. To tackle the problem, lime addition is one of the solutions. The lack of soil specific lime recommendation method(s) to amend the increasing acidification problem has been one of the challenges to boost crop production. Therefore, a greenhouse experiment to select best-fit LR method(s) and calibrate on Luvisol was conducted. Different LR methods were evaluated to find out which of these methods most accurately predicted the LR in comparison with reference CaCO3‐incubation. The initial LR dose for incubation experiment was calculated using Shoemaker, Mc lean and Pratt (SMP) method to achieve a target pH of 6.0, followed by progressive incremental addition of lime. Then, the soil was incubated with different doses of CaCO3 for a period of five weeks to achieve different target pHs. The results of incubation were compared with the buffered and unbuffered LR methods. The CaCO3 incubation pH measurement results showed an increasing trend with an increasing amount of lime added. The LR prediction ability of exchangeable acidity and single addition Ca (OH)2 were the least of all the methods tested for Luvisol, when compared to the reference method. Adams Evan and modified Mehlich LR predication are next to incubation in LR prediction for Luvisol. However, more researches that are detailed are needed to verify and synchronize the greenhouse results with field experiment in different agro ecologies to increase nutrient supply to the plant, water percolation and crop production. Key words: Acidity, luvisols, lime, lime requirement, Shoemaker, Mc lean and Pratt (SMP), modified Mehlich.

Effect of graded compaction of tilled and untilled sandy loam soil on growth and yield of maize

Abstract: The performance of maize on tilled and untilled sandy loam soil, under different levels of compaction of 0, 2, 4 and 6 tractor-wheel passes in a humid tropical environment was investigated with a Massey Ferguson (MF) 90-disc plough, mounted on an MF 260 tractor. The experimentation had different aspects, respectively conducted in the field and laboratory, at the Rivers State University, Port Harcourt, Nigeria. The experimental field was a 72 m2 plot of land, which was left fallow for two years before the investigation. The plot was sub-divided into five experimental subplots of 9 m2 each, numbered 1 to 5, with a furrow spacing of 0.5 m. Soil samples were taken randomly at a depth of 0.3 m for the determination of the soil physical properties. After the compaction treatments, maize seeds were manually planted at a depth of 0.05 m and the growth and yield of the maize monitored over a period of fourteen weeks after planting. The investigation showed that the maize crop performed optimally on subplot (2), which was tilled and un-compacted, with a dry matter content of 2,859 kg ha-1, while the least performance was on subplot (1) that was untilled and un-compacted, with a dry matter content of 1,192 kg ha-1. Therefore, this research establishes that, with the agricultural practice of shifting cultivation, sandy loam soil in a humid tropical region requires a minimum level of tillage to achieve optimal yield of maize crop. Key words: Maize, compaction, growth and yield, tilled soil, untilled soil, sandy loam.