Thresholds of gully erosion in the coastal plains sands of southeastern Nigeria

The concept of geomorphic threshold as applied in gully erosion studies assumes that water erosion occurs when the combined power of the rainfall energy and overland flow exceeds the resistance of surface materials to detachment and entrainment. This line of reasoning presupposes that certain environmental factors that affect runoff generation and erodibility status of soil can be used in estimating thresholds for gully initiation and sustenance. The entire 413. Km2 Ikpa River basin was covered with grids 1km2 and random number table was used to select 15% of the target population in the basin. The pair-wise correlation technique was employed to establish the threshold values of vegetation cover, organic matter content, relief, slope gradient, litter cover and bulk density for gully incision and development in the fifth order drainage basin underlain by Coastal Plains Sands in eastern Nigeria. The results of the analyses indicate that the threshold value of vegetation cover was 72.5%, while the thresholds value of depth of litter cover was 3.2cm. Other threshold values for gully initiation in the catchment area were 1 degree for slope gradient; 2.70% for organic matter; and 10metres a.s.l for relief. These threshold values were exceeded in almost all the sampled gully sites. The results of the research have implications for cropping in the study area. The convectional rain-storms that is associated with the beginning of the planting season in April/May cannot be controlled by man. Its effects can be reduced to desirable level by increasing the surface contact cover. Mulching, intercropping and the planting of cover crops can ensure adequate vegetation cover of >72.5% on valley –side slopes. Also, crop residue, dry stalks and stovers should be used to encourage the build-up of organic matter above the critical level of 2.70% during the planting season.KEYWORDS: Gully erosion, threshold, Ikpa river, coastal plains, morphometry, intrinsic factor

A spatio-temporal synchronization of periodic markets: Evidence from the hinterland of Akwa Ibom state

This study seeks to identify the ‘rings’ of periodic market days in Akwa Ibom State, using eighteen periodic markets as case study The entire landmass of the state was covered with a network of grids. These grids were numbered and a table of random numbers was used in selecting a target population of eighteen communities in the hinterland of the state. The base map of Akwa Ibom State at a scale of 1;750,000 was scanned [and geo-referenced using Erdas Imagine 8.5 software], exported into a GIS environment and digitized using Arcview 3.1.This facilitated the mapping of the spatial distribution of the selected markets. The ‘rings of market days’ in the study area was also displayed graphically and the results indicate that rural markets appear to have been sequenced in such a way that spatial and temporal competition are rendered complementary. In the study area, the eight –day markets are common [56% of selected markets];4-day(27.5%);weekly(11%])and 3-day cycle(5.5%0. Some of the traditional markets are named after the market days, for instance, Etaha Itam and Obo Annang markets in Itu and Essien Udim LGAs respectively. The rural/traditional markets deal on low order goods and are mainly agricultural produce, hence the numerous periodic markets in rural/suburbs are bulk-building points for agricultural produce [as they supply farm produce to the urban markets]. More importantly, the rural economy is characterized by very low per capita income and weak purchasing power. Market days are usually spaced in time to allow a sufficient build up of effective demand, and sometimes also of suppl

Comparative analysis of type 1 and type 2 cassava peeling machines

A comparative analysis of type 1 and type 2 cassava peeling machines with nail lengths of 26mm and 20mm were investigated in order to improve peeling techniques of cassava tubers. The machines were evaluated at four (4) different speeds; (80rev/min, 90rev/min, 100rev/min, and 110rev/min), with 750HP petrol engine. Cassava tubers were graded into average weights of 0.81kg, 0.72kg, 0.64kg, 0.55kg, 0.50kg. The results of the properties evaluated for type1 and type 2 peelers are: Weight of peeled cassava (85% and 78%) at 80rev/min respectively, Weight of cassava peels (16% and 15.66%) at 80rev/min respectively, Weight of cassava flesh loss (0.7% and 3.26%) at 80rev/min respectively, weight of unpeeled cassava (0.7% and 3.26%) at 80rev/min respectively, Peeling efficiency (88% and 82%) at 80rev/min respectively, Mechanical damage (0.0084kg and 0.040kg) at 80rev/min respectively, Throughput capacity (1041kg/h and 1149kg/h) at 110rev/min respectively, The results of the properties evaluated for type 1 peeler were better than type 2 peeler.Key words: Nails, Weight, Cassava, Peelers, Flesh loss

Simulation and Experimental Validation of solar water heater operating with selected Phase Change Materials

Solar water heaters are widely known for their application in the domestic sector for heating water using free sunlight. However, the stochastic nature of sunlight especially in the tropical parts of the world, has created the need for some form of thermal energy storage to buffer the effect of the randomly varying solar insolation, and also to ensure a steady hot water delivery even during the night time, when the solar insolation is absent. This paper experimentally and numerically studies (using CFD software) the behavior of a solar water heater operating in the tropical climate of Nsukka, Nigeria, (Latitude 6.854oN longitude 7.29oE), incorporated with cetyl alcohol (Melting point: 47℃-50℃), palmitic acid (Melting point: 63℃-65℃) Myristic acid (Melting point: 50℃-53℃) and stearic acid (Melting point: 69℃-70℃)  as thermal energy stores. The experiments were carried out during the rainy season, with an average relative humidity of 83.26% and solar irradiance of 250W/m2. The maximum average collector box temperature recorded was 55.62℃. The thermal performance of a solar water heater operating with cetyl alcohol, palmitic acid, myristic acid and stearic acid was measured, paying specific attention to their charging performance and hot water delivery during nighttime. A CFD model is also developed using ANSYS FLUENT and is used to simulate the collector box, hot water and PCM temperatures. The CFD model developed, predicted the PCM and hot water temperatures with a Root Means Square Error of 3.05℃ and 3.64℃ respectively, and with a Nash Sutcliffe accuracy of 98% and 99% respectively. Keywords: Energy Storage, CFD, Solar Water Heater, Latent Heat, Collector, Solar Energy DOI: 10.7176/JETP/10-5-05 Publication date:September 30th 202

Fifty years of oil exploration in Nigeria: The paradox of plenty

It is expected that countries with an abundance of natural resources should prosper. Yet over many years, it has been observed that nations rich in oil, gas, or mineral resources have been disadvantaged in the drive for economic progress. The concept of resource curse which refers to theobservation that nations with rich endowments of natural resources [oil as in the case of Nigeria] often dramatically under perform economically relative to what one would expect was used in this study. The methods employed in data collection, primarily from secondary sources include; literature review of NNPC publications, national dailies and newsmagazines; internet reports on OPEC, oil production in Nigeria, etc. Descriptive statistic was used in data analysis. The results revealed that the oil wealth was initially well applied towards the development of the country. Overtime, successive governments began to mismanage it and a situation like this had given rise to other contemporary oil nations overtaking Nigeria. The consequence is that the early gains of oil disappeared in the face of declining quality of general infrastructure across the country. The growingreliance of the country on oil and gas alone may undermine the democratic structure-rule of law, political stability [as in the case of militancy in the Niger Delta region], government effectiveness and the fight against corruptio

Fifty years of oil exploration in Nigeria: the paradox of plenty

It is expected that countries with an abundance of natural resources should prosper. Yet over many years, it has been observed that nations rich in oil, gas, or mineral resources have been disadvantaged in the drive for economic progress. The concept of resource curse which refers to the observation that nations with rich endowments of natural resources [oil as in the case of Nigeria] often dramatically under perform economically relative to what one would expect was used in this study. The methods employed in data collection, primarily from secondary sources include; literature review of NNPC publications, national dailies and newsmagazines; internet reports on OPEC, oil production in Nigeria, etc. Descriptive statistic was used in data analysis. The results revealed that the oil wealth was initially well applied towards the development of the country. Overtime, successive governments began to mismanage it and a situation like this had given rise to other contemporary oil nations overtaking Nigeria. The consequence is that the early gains of oil disappeared in the face of declining quality of general infrastructure across the country. The growing reliance of the country on oil and gas alone may undermine the democratic structure-rule of law, political stability [as in the case of militancy in the Niger Delta region], government effectiveness and the fight against corruptionKEYWORDS: Resource curse, Nigeria, Oil and Gas, GDP, Infrastructure, Corruptio

Towards a genuinely participatory approach to poverty alleviation in Uyo LGA, Akwa Ibom state

Research evidence shows that commercial banks are not keenly interested in financing agriculture The commercial banks on the other hand argue that the farmers and governments have not provided a default risk-reducing environment to enhance lending. In the light of the foregoing , the participatory rural appraisal technique [PRA] is being proposed as a remedy for rapid transformation of the agricultural sector/poverty reduction. There is the need therefore for a thorough insight into the different dimension of default risk as a means of suggesting some ways by which it could be reduced. It is for this reason that PRA was employed in this survey to identify potential beneficiaries before evolving the loan scheme. It is crucial as we can now maintain close contact with the borrowers through regular visit to keep the obligation constantly before him

Seasonality of surface water contamination by heavy metals in the lower Enyong creek, s.e. Nigeria)

Surface water samples from three locations in the Lower Enyong Creek, S.E. Nigeria were sampled over six months i.e June to October (wet season) and November in dry season for heavy metals such as Cd, Mn, Fe, Cu, Ni, Pb, Zn, Cr) using Atomic absorption spectroscopic method. Some specific physicochemical characteristics, such as temperature, hardness, alkalinity, salinity, TDS, TSS, pH and conductivity which are known to influence the interactions and dynamics of trace metal loads in water bodies were also determined. The result of the analysis indicated significant monthly variation of these parameters for the six months. Monthly summary statistics revealed a few seasonal patterns that echoed the hydrologic regime. During the short dry season in August–September period, all the sampled stream channels had lower levels of Cd, Ni, Zn, Cu Cr, Pb and Fe. Salinity, for instance, correlated strongly (p<0.05) with Cu (0.70); Cr (0.56); Ni (0.72); nitrate (0.61) and Na (0.49). However, the concentrations of most heavy metals were low, while Zn content was higher than the WHO standard for surface water which indicated significant contamination by Zn in the water body

Source Evaluation and Trace Metal Contamination in Benthic Sediments from Equatorial Ecosystems Using Multivariate Statistical Techniques

race metals (Cd, Cr, Cu, Ni and Pb) concentrations in benthic sediments were analyzed through multi-step fractionation scheme to assess the levels and sources of contamination in estuarine, riverine and freshwater ecosystems in Niger Delta (Nigeria). The degree of contamination was assessed using the individual contamination factors (ICF) and global contamination factor (GCF). Multivariate statistical approaches including principal component analysis (PCA), cluster analysis and correlation test were employed to evaluate the interrelationships and associated sources of contamination. The spatial distribution of metal concentrations followed the pattern Pb>Cu>Cr>Cd>Ni. Ecological risk index by ICF showed significant potential mobility and bioavailability for Cu, Cu and Ni. The ICF contamination trend in the benthic sediments at all studied sites was Cu>Cr>Ni>Cd>Pb. The principal component and agglomerative clustering analyses indicate that trace metals contamination in the ecosystems was influenced by multiple pollution sources