Journal of Soil Science and Environmental Management, 2020
The performance of maize on tilled and untilled sandy loam soil, under different levels of compac... more 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 m 2 plot of land, which was left fallow for two years before the investigation. The plot was subdivided into five experimental subplots of 9 m 2 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.
Agricultural Engineering International: The CIGR Journal, 2019
A mathematical model has been developed for the prediction of soil compaction effects on the grow... more A mathematical model has been developed for the prediction of soil compaction effects on the growth and yield of maize crop in a sandy loam soil in tropical climates. The field work was done at the teaching and research farm of Rivers State University, Port Harcourt, Nigeria. A plot of land measuring 18 m x 4 m was divided into five sub-plots of equal dimensions and labelled as: plot 1 – un-compacted and untilled; plot 2 – un-compacted but tilled; and plots 3, 4 and 5 - tilled and compacted to varying degrees of tractor passes, viz 2, 4 and 6 tractor passes respectively. A Massey Ferguson (MF) 90 model disc plough was used for the tillage and an MF 260 model tractor used for the soil compaction treatments. Irrigation, weed and pest control were done equally on all plots when necessary. The maize crops were planted in the month of October and grew to maturity fourteen weeks thereafter. Field measurements gave values of soil bulk densities and moisture contents as 1.20, 1.17, 1.23, 1....
International Journal of Water Resources and Environmental Engineering, 2016
This study was conducted to investigate the combined effects of municipal and industrial waste di... more This study was conducted to investigate the combined effects of municipal and industrial waste discharges on the quality of the new northern Calabar River in the Niger Delta province (5.317°N, 6.467°E) of Nigeria. Water samples were collected in June 2015 from five regions along the stretch of the river. The five regions comprised three observed pollution sources (abattoir, open market, and noodle factory) and two non-pollution sources at the downstream and upstream sections of the river. Using standard analytical protocols, results showed that the current pollution loads of the river varied significantly (p < 0.05) across the three pollution sources. Over 33% of studied quality indicators of the river including total hardness (1526.19±154 mg/l), biochemical oxygen demand (10.14±4 mg/l), and chemical oxygen demand (57.62±13 mg/l) over time increased beyond their permissible limits due to the disposal of municipal and industrial wastes into the river. The present quality of the river was only fair with a Water Quality Index of 64.71. This result suggests that the water quality is usually protected but occasionally impaired by the wastes discharged into the river, leading to conditions that often depart from permissible levels.
The effect of septic tank locations on borehole water quality in Port Harcourt, Nigeria
The effect of septic tank location on borehole water quality in five locations in Port Harcourt m... more The effect of septic tank location on borehole water quality in five locations in Port Harcourt metropolis of Rivers State, Nigeria, was investigated. The locations were Miles I and III, Old GRA, Rukpoku, and Ada George. Three boreholes and septic tanks were involved in each location. The distance between each borehole and septic tank was measured, while water sample from each borehole was analysed for parameters such as appearance, taste, pH, electrical conductivity, temperature, salinity, and turbidity. Other parameters were total dissolved solids (TDS), phosphate, sulphate, nitrate, ammonium, chloride, alkalinity, dissolved oxygen, bio-chemical oxygen demand, total heterotrophic bacteria (THB), total coliform bacteria (TCB), and faecal count bacteria (FCB). The results obtained from the various locations were compared with WHO drinking water quality standard. From the results, there was no problem with appearance and taste. However, the highest pH value was 4.4 from both Mile III...
Production of biodiesel from TGX-1778 soybeans (Glycine max) by sodium hydroxide-catalysed transesterification
This study investigated the potential of a Nigerian-grown soyabean (TGX-1778) to produce biodiese... more This study investigated the potential of a Nigerian-grown soyabean (TGX-1778) to produce biodiesel. The soybeans at room temperature were dehulled, ground to a powdery form, and the oil extracted by Soxhlet extraction method using n-Hexane. 50 ml of the soybean oil extract and 0.5 g of NaOH were charged into three different reactors labelled A, B, and C, and transesterified in turn with 50, 100, 150 ml of methanol respectively. Results showed that transesterification with 50, 100, and 150 ml of methanol produced biodiesel of densities 0.79, 0.80, and 0.77 g/ml respectively, while the corresponding kinematic viscosities at 40 0C were 4.4, 4.6, and 4.1 mm2/s. Other parameters of the biodiesel were refractive index, which ranged from 1.33 to 1.34, pH from 8.5 to 9.6, cloud point (< -32 0C), pour point (-52 0C), and flash point (150 0C). Comparison with the American Society for Testing and Materials (ASTM) D6571 standard indicated that the densities were outside the specified range, ...
Treatment of Automotive Gas Oil (AGO)-contaminated water using activated carbon from Indian bamboo
This study investigated the ability of activated carbon extracted from Nigerian-grown Indian bamb... more This study investigated the ability of activated carbon extracted from Nigerian-grown Indian bamboo, to absorb hydrocarbon from automotive gas oil -contaminated water. The water was polluted in the ratio of 3:1 (that is, 3parts of water to 1part of automotive gas oil), and then made to flow through 250μm and 500μm activated carbon in a fixed bed adsorption experimental set-up. The effluent from each size of activated carbon was then analysed. The result showed that the activated carbon’s ability to reduce contaminants was, in part, a function of its pore size. Although, the two pore sizes of the activated carbon were able to achieve almost 100% reduction of total petroleum hydrocarbon (TPH) and total hydrocarbon content (THC), the 250μm pore size could only reduce 67.7% of the hydrocarbon utilizing fungi count, compared to 70.4% by the 500μm size. For the hydrocarbon utilizing bacterial count, the levels of reduction were 68.6% and 73.2% for 250μm and 500μm respectively. On the whol...
This study evaluated the efficacy of using Tween 80 surfactant (TW80) and food-waste anaerobic di... more This study evaluated the efficacy of using Tween 80 surfactant (TW80) and food-waste anaerobic digestate fibre (FWAD) as soil amendments for the remediation of wetlands contaminated by crude oil. A 112-day mesocosms experiment was carried out to simulate hydrocarbon degradation under typical acidified wetland conditions. Soil was spiked with 50,000 mg kg−1 crude oil and TW80 and FWAD were added to mesocosms at 10%, 20% and 30% w/w. The soil basal respiration, microbial community dynamics, environmental stress, alkanes, and PAHs degradation were monitored throughout the mesocosm experiment. Amending the mesocosms with FWAD and TW80 enabled the recovery of the soil microbial activities. This was evidenced by soil basal respiration which was the highest in the 30% FWAD and 30% TW80 mesocosms and translated into increased degradation rate of 32% and 23% for alkanes, and 33% and 26% for PAHs compared to natural attenuation, respectively. Efficient total hydrocarbon degradation was achiev...
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