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Aims: Soils in Ghana's coastal savanna are typically poor in phosphorus (P), which has an impact on crop growth and productivity. The majority of West African phosphate rock formations are not reactive; therefore, their direct applications do not facilitate easy P availability to crops. Co-composting organic waste with phosphate rock and using phosphorus-solubilizing microorganisms is the new paradigm adopted by scientists in response to the lack of P availability (PSMs). The goals of this study were to (1) assess the effect of Aspergillus niger in P dissolution in phosphate rock during composting with citrus waste (CW) and rice straw (RS) and (2) to evaluate the effect of phosphor-compost on growth, dry matter yield and P uptake of maize. Methodology: Preparation of compost took place at University of Ghana Forest and Horticulture Research Center, Okumaning Camp close to Kade. Citrus waste and rice straw were used as feed stock. Each composting pile contained a mixture of urea, Togo phosphate rock, and feedstock in a 1:3:24 weight-to-weight ratio. Results: According to the findings, citrus waste feedstock was superior to rice straw in dissolving the P in rock phosphate. In a pot experiment, the phospho-composts were assessed using maize (Zea mays) as the test crop.

Field experiment was conducted to investigate the response of soil physical properties, crop growth, yield and yield components of watermelon to different tillage methods in the transitional zone of Ghana in a two year period. The tillage treatments used in the study were plough and harrowed (PH), minimum tillage (MT) and no tillage (NT) which was laid out in a Randomized Complete Block design (RCBD) with 3 three replications. The two field experiments were undertaken at the experimental site of the University of Education, College of Agriculture, Mampong-Ashanti, (7°08‘ N, 1°24‘ W )located within the transitional agro-ecological zone between the forest and Guinea Savannah zones characterized with two rainfall regimes with an annual rainfall of 1094.2 mm with 30°C temperature. The soil belongs to the Bediase series with ochrosol type formed from voltain sandstone and a pH between 5.5 to 6. The statistical analysis revealed that, tillage methods significantly affected soil physical properties particularly, total porosity, volumetric water content and bulk density. Also, tillage methods influenced crop growth, (number of leaves and vine length), yield and yield components of watermelon in the order of Plough and harrowed > Minimum tillage > No-Tillage in almost all the treatments. Accordingly, the ploughed and harrowed (PH) was found to be more appropriate and profitable tillage method to improving soil physical properties, crop growth, yield and yield components of watermelon in the forest-transitional of Ghana.

The use of inorganic fertilizer to produce most vegetables in Ghana like carrot is in ascendency in Asante Mampong and its environs and its continuous use has a rippling effect on soil health and productivity and the high cost of these fertilizers is a challenge to most poor resourced farmers in Ghana. A field experiment was conducted during the major raining season in 2010 at the University of Education Winneba, Faculty of Agriculture Education research field at Mampong in the forest-transitional zone of Ghana on the Bediase series. The objective of the study was to evaluate the effect of grasscutter manure in combination with NPK fertilizer on soil physical and chemical properties, growth and yield of carrot. The treatments were 300 kgNPK/ha, combination of half rate NPK fertilizer and different rates of grasscutter manure (GM) thus; (5tGM1/ha+150 kgNPK, 7.5tGM2/ha+150 kgNPK and 10tGM3/ha+150 kgNPK/ha) and control (without amendment) and the experiment was laid out in a randomized complete block design with 3 replications. Results indicates that application of grasscutter manure in combination with NPK fertilizer significantly improved the soil physical conditions particularly, soil bulk density, total porosity, and gravimetric moisture content than the NPK alone and the control. Compared with the control, the treatment combinations significantly increased soil organic carbon, N, organic matter concentrations and exchangeable cations. Plant height, number of leaves, tap root length and root yield of treatment combinations were higher than NPK and the control. Also the treatment combinations significantly reduced nematode presence and number of roots deformed. For good soil health, grasscutter manure in combination with NPK would be better than either manure or NPK alone.

In this paper a comparative study of cavity defects partial discharge in single and double cavities was performed at different applied voltages. The variation of the PD magnitudes and phase-resolved-patterns (PDPRP) are studied as a function of increasing supply voltage magnitude. The study is conducted on polymer insulation discs. Two test samples were prepared. Sample 1 consist of a cavity of 0.1 mm thickness and sample 2 with 2 of 0.1 mm cavities positioned 0.1 mm apart in the middle of the insulation. The PD magnitude of the double voids are affected significantly by the increase in applied voltage compared to the single cavity magnitude. The PDPRP however are invariant. An electric field simulation model was created using QuickField Software to investigate the electric field distribution profiles in the insulation model. The simulation results correlated with the measurement results.

The experiment was conducted to assess the influence of grass mulch on some soil physical attributes of a luvisol and water requirement of cowpea in the transition zone of Ghana at the University of Education, Winneba, Mampong campus. A Randomized Complete Block Design (RCBD) was used. The grass mulch rates were; 1 t ha-1, 3 t ha-1, 5 t ha-1 and control (no mulch) with four replications. The grass mulch was applied evenly on the soil surface under a cultivated cowpea. Parameters assessed were soil aggregate stability, bulk density, soil porosity, soil gravimetric and volumetric moisture contents, cumulative infiltration, sorptivity, organic matter content and cowpea seed yield. The study showed that mulching improved cowpea seed yield, soil gravimetric moisture content, soil volumetric moisture content, cumulative infiltration amount, infiltration rate, sorptivity and soil residual moisture. The soil physical parameters measured in both the minor and major seasons were higher on the 5 t ha-1 plots but lower on the control (no mulch) plots. There was a significant (P = .05, r = 0.61) positive correlation between the cowpea seed yield and soil gravimetric moisture content. Estimation of water requirement of cowpea using the Blaney-Criddle method produced higher values in 2010 (629.70 mm season-1), 2011 (619.60 mm season-1) than the field graphical estimated values in 2010 (399.00 mm season-1), 2011 (357.0 mm season-1) and improvised evaporation pan values in 2010 (347.90 mm season-1), 2011 (136.11 mm season-1) seasons Although cowpea is tolerant to water deficit to some extent, the use of 5 t ha-1 mulch for sustainable soil moisture management would be important in areas of erratic and inadequate rainfall.

This study presents the simulation of the electrical field distribution in voids encapsulated in epoxy insulation material using QuickField™ software. The significance of this study is to further understand how electric field distribution influences partial discharge activity in insulation material containing air voids. The insulation model consists of single and double voids located in the middle of the insulation. The simulation results indicate that the electric field in the single void is higher than in the case of two voids adjacent to each other. However, despite the voids being identical to the enhancements of the electric fields in the voids is not to the same extent.

Electrical insulation is one of the most critical parts of most of high voltage power system equipment, and its quality plays a significant role in determining the reliability of the equipment. Most common problems of power equipment are associated with insulation failure. Partial discharges are common problems in electrical insulation. Measurement of partial discharge is therefore widely used to diagnose the condition of the insulation system. Hence, it is imperative to study how partial discharge activity can be analyzed in insulation material containing multiple cavities. The objective of this paper is to apply the Phase-Resolved Partial Discharge Analysis (PRPDA) technique to insulation with single and two cavities close to each other in order to investigate the behavior of the partial discharge activity. Through the analysis of the experimental results, it was established that phase-resolved partial discharge pattern for two cavities is different from that of the single cavity pattern.

The study assessed the response of hydro-physical properties of Chromic Luvisol to different methods of application of Mucuna pruriens as a soil amendments in two separate experiments. A Randomized Complete Block Design (RCBD) with three replications was used with the following treatments: 7.04t/ha Mucuna pruriens as green manure (GM), 7.04t/ha Mucuna pruriens as live mulch (LM), 7.04t/ha Mucuna pruriens as in-situ mulch (IM) and a control plot which had no Mucuna pruriens as soil amendment. Data were collected on gravimetric (θ_g) and volumetric moisture content ( θ_v), residual moisture storage(R), sorptivity(s), cumulative infiltration (I), bulk density (ρ_b), total porosity (f), aeration porosity (ξ_a), aggregate stability (ASt) and soil temperature, for assessment of hydro-physical properties of the soil. The results from the experiments indicated that Mucuna pruriens as live mulch used as amendment significantly reduce bulk density (ρ_b), increased total porosity (f) and aeration porosity (ξ_a) thus it gave significant improvement on those soil physical properties measured while Mucuna pruriens as in-situ mulch improved aggregate stability (ASt) and gave optimal soil temperature. In the assessment of soil volumetric moisture content ( θ_v), residual moisture storage(R), sorptivity(s), cumulative infiltration(I), the study shows that Mucuna pruriens as in-situ mulch recorded the optimal values and was closely followed by Mucuna pruriens as live mulch.