Open Access Original Research Article

Study on the Distribution of Heavy Metals in Different Tissues of Fishes from River Benue in Vinikilang, Adamawa State, Nigeria

J. C. Akan, M. Salwa, B. S. Yikala, Z. M. Chellube

Current Journal of Applied Science and Technology, Page 311-333
DOI: 10.9734/BJAST/2012/1716

Aims: This study is aimed to determine the levels of some heavy metals in different species of fish and to compare the results with other standard values. 
Study Design: The gills, liver, stomach, kidney, bones and flesh of four common fish species (Tilapia zilli, Clarias anguillaris, Synodentis budgetti and Oreochronmis niloticus) were collected for analysis of heavy metals. 
Place and Duration of Study: This study was carried out in River Benue, Vinikilang, Adamawa State, Nigeria between the periods of January 2011 to January 2012. 
Methodology: Sample collection and preparations were carried out using standard procedures. The concentrations of Cu, Zn, Co, Mn, Fe, Cr, Cd, Ni and Pb were carried out using Flame Atomic Absorption Spectrophotometer (AAS, Unicam 969). 
Results: Iron was the most abundant metal in the studied tissues of all the fish species. In the fishes analyzed Fe accumulation was the maximum in all the organs but its highest value of 12.65 µg/g was significantly observed in the Gills of Synodentis budgetti (p <0.05), the liver of Tilapia zilli was second while the flesh of Heterotis niloticus shows the least value. From the result of this study, the tissues accumulation was observed in the order of gills>liver>stomach>kidney>bones>flesh. The gills of all the fish tend to accumulate significant high levels of heavy metal than other tissues. Accumulation of metal in different species is the function of their respective membrane permeability and enzyme system, which is highly species specific and because of this fact metals accumulated differently in the tissues of fishes as observed in the study. 
Conclusion: Based on the above results, it can therefore be concluded that metals bioaccumulation in the entire fish species study did not exceeds the permissible limits set for heavy metals by FAO, FEPA and WHO. Therefore these fishes are fit for consumption.

Open Access Original Research Article

Groundwater Modelling, An Effective Tool in the Assessment of Groundwater Contamination: A Case Study of Umunwanwa in Umuahia-South, Abia State, Nigeria

C. Amos-Uhegbu, M.U. Igboekwe, K.T. Eke, R.U. Adindu

Current Journal of Applied Science and Technology, Page 334-355
DOI: 10.9734/BJAST/2012/1518

To determine the environmental suitability (impacts on groundwater) of an excavated pit located within the eastern boundary of Umunwanwa for any form of waste discharge (sewage or solid waste), modelling approach was adopted. A thorough geophysical / hydrogeological investigation carried out in the area revealed the existence of 7 layers and in the vicinity of the site an unsaturated semi-permeable zone with clay lenses. Site specific hydraulic conductivity of 9m/d was determined through grain size analysis. The groundwater flow direction of the area is from south-east to north-west and the flow system consists of two aquifers separated by a 6.1m thick confining layer. The simulation was carried out for short and long term assessment which gave rise to two sample problems.
Sample Problem 1: (Upper aquifer) which is the “Modelling of Groundwater Mound Resulting from Effluent Infiltration,” where analytical and numerical models for calculating the groundwater mound were applied. Ten analytical simulations with recharge rates varying from 0.003125m/d to 0.75m/d were carried out. After 100days there was no significant rise in the groundwater table with recharge rates less than 0.0375m/d, while recharge rates above 0.0375m/d gave significant groundwater mound. A further numerical simulation using a recharge rate of 0.75m/d showed that the results of analytical and numerical simulations are found to be in good agreement by predicting that at the end of 50 days a 12m groundwater mound beneath the centre of excavated pit is expected. 
Sample Problem 2: (Lower aquifer) is the “Modelling of Solute Transport Resulting from Effluent (Leachate) Infiltration”, where a particle tracking technique introduced uses a semi-analytical particle tracking scheme that allows an analytical expression of the particle’s flow path to be obtained within each finite-difference grid cell. Particle paths are computed by tracking particles from one cell to the next until the particle reaches a boundary, an internal sink/source, or satisfies some other termination criterion while keeping track of the time of travel for particles moving through the system. After 15 years, the contaminant plume was able to reach the well head. This has shown the effectiveness of groundwater modelling in the assessment of groundwater contamination thus revealing the unsuitability of the site for any form of waste discharge.

Open Access Original Research Article

Nutritional and Sensory Characteristics of an Infant Food Based on Soybean Seeds (Glycine max) and Tigernut Tubers (Cyperus esculenta)

C. A. Emmanuel- Ikpeme, I. O. Ekpeyoung, G. O. Igile

Current Journal of Applied Science and Technology, Page 356-366
DOI: 10.9734/BJAST/2012/1341

Aims: To evaluate the nutritional and sensory characteristics of soybean and tigernut based infant food that could be adoptable at house-hold level by rural dwellers.
Study Design: Randomized design.
Place and Duration of Study: Department of Biochemistry, University of Calabar, between January 2009 and 2010.
Methodology: Soybean seeds were washed, soaked overnight, cooked, dehulled, dried and milled into flour to pass a 300µm sieve. Tigernut tubers were washed, soaked for 96h, dried and milled into flour (300µm). Three weaning foods; STF1 (Tigernut: 75%; soybean: 15%); STF2 (Tigernut: 65%; Soybean: 25%); STF3 (Tigernut: 55%; Soybean: 35%) with 10% full cream powdered milk (FCM) each were prepared to yield formulated weaning food (FWD). Samples were assayed for proximate, energy, pH, mineral and organoleptic qualities. The control was a commercial brand based on maize, soybean, FCM and additives.
Results: Proximate, energy and mineral contents of the samples were different (P<0.05). FWDs contained higher (P<0.05) amounts of protein, ash, fat, fiber, energy and mineral contents than the control. STF3 recorded higher (P<0.05) ash, protein, fiber, calcium, potassium, magnesium, iron and zinc. Among the FWDs, STF3 had higher (P<0.05) panelists ratings for all the sensory attributes and it compared favorably with the control. STF3 was rated higher (P<0.05) for overall acceptability compared to the control. The result suggested that STF3 hold a potential promise for the delivery of cheap nutrient dense infant food for low income house-holds. 
Conclusion: The potential suitability of tigernut flour in weaning food formulation was shown in this study. Although all the formulated diets met the benchmark for infant food, taking into consideration the dietary profile and sensorial ratings, STF3 (Tigernut 55%; Soybean 35%, 10% milk) was found to be the most promising formulation. This indicates that underutilized tigernut tubers could be exploited to produce adoptable household cheap weaning food with soybean that can compare favorably with commercial brand. This could be a sustainable way of curbing malnutrition in sub-Saharan Africa.


Open Access Original Research Article

Experimental Determination and Modelling of the Sorption Isotherms of Kilishi

André Talla

Current Journal of Applied Science and Technology, Page 379-389
DOI: 10.9734/BJAST/2012/1888

Sorption isotherms of kilishi have been experimentally determined at 30, 40 and 50ºC by using salt method for a range of water activity from 0,064 to 0,973. His sorption capacity increases with the temperature for a given water activity. The experimental curves obtained have been simulated by the GAB model. This model enables the representation of the whole desorption isotherms, with maximum deviation of 1.2%kgw.kgdm-1. The water content corresponding to monolayer saturation was estimated. The isosteric heat of sorption is deduced from experimental results and empirical correlations are proposed leading to satisfactorily representation. These results can be used to predict the potential changes in kilishi stability and later for the development of a system of suitable drying.


Open Access Original Research Article

Spatial Analyses of Illiteracy and Unemployment at Governorate Level in Egypt

Faisal G. Khamis

Current Journal of Applied Science and Technology, Page 390-405
DOI: 10.9734/BJAST/2012/1682

The objective is to investigate the spatial pattern of each of illiteracy rate (IR) and unemployment rate (UR) and the spatial correlation between these patterns. This study is important for both researchers and policy makers. The study design was cross-sectional data analysis. The present study utilizes census data conducted in Egypt in 2006 for 27 governorates. Mapping was used as the first step to conduct visual inspection for IR and UR. Several spatial econometric techniques are available in the literature, which deal with the spatial autocorrelation in geographically referenced data. Two statistics of spatial autocorrelation, based on sharing boundary neighbours, known as global and local Moran’s , were carried out. Wartenberg’s measure was used to detect the bivariate spatial correlation between IR and UR based on simulation study. The hypothesis of spatial clustering for IR was not confirmed by a positive global Moran’s of .03. While for UR, it was confirmed by a positive global Moran’s of .25 with . The bivariate spatial correlation between IR and UR was found -.19 and . Based on visual inspection of mapping, global clustering was found for IR in western-northern and middle governorates and for UR in eastern-northern and southern governorates. Global clustering was found for UR but was not found for IR based on spatial measure. Out of 27 governorates, two were found as local clusters in each of IR and UR. The bivariate spatial correlation between IR and UR was not found significant.

Open Access Original Research Article

Hydrogeophysical Delineation and Hydrogeochemical Characterization of the Aquifer Systems in Umuahia-South Area, Southern Nigeria

C. Amos-Uhegbu, M. U. Igboekwe, G. U. Chukwu, K. O. Okengwu, T. K. Eke

Current Journal of Applied Science and Technology, Page 406-432
DOI: 10.9734/BJAST/2012/1645

In Umuahia-South Local Government Area of Abia State Nigeria, some cases of boreholes failure and groundwater discolouration have been observed. An investigation in order to determine the hydrogeological conditions of the area was carried out using geoelectrical, drill-hole and hydrogeochemical data. Using the Schlumberger electrode configuration, ten vertical electrical sounding data were acquired and the computer-aided Resist software method was used for further processing and interpretation. The interpretation of the VES data obtained from the study area shows that the vicinity of VES station 1 is likely to record failure in bore-hole exploration. A high variation in aquifer thicknesses is observed with the least as 27m at VES Station 5, and the highest 226m at VES Station 3. A new approach was used in the estimation of aquifer hydraulic parameters such as hydraulic conductivity and transmissivity. Some geoelectric sections generated from VES stations were compared with some lithologs which gave a good geological description of the study area; thereby revealing a multi-aquifer hydrogeologic system. Water samples were taken from ten boreholes for hydrogeochemical investigation which reveals the occurrence of same geochemical process; but slightly varying water quality which is associated to the multi-aquifer status of the area. The discolouration of water observed in some boreholes owes its origin from the silty-sand aquiferous units with slightly high iron content. A further analysis of the samples when plotted on Gibb’s Diagram reveals that recharge occurs through precipitation, but the local geology of the area is the source of major ion concentrations in the samples.

Open Access Review Article

Adapting Nigeria Cities to Climate Change using Design Options: A Review

Ifeanyi C. Enete, M. C. Officha, A. M. Ezezue, P. C. Agbonome

Current Journal of Applied Science and Technology, Page 367-378
DOI: 10.9734/BJAST/2012/1696

Problem Statement: Nigeria like the rest of the entire continent of Africa is considered highly vulnerable to climate change because of its high exposure and sensitivity, limited adaptive capacity, poverty, illiteracy, food insecurity, and disease all of which interact with Climate change.
Approach: The aim of the study is to introduce the need to utilize design options as an approach to climate change adaptation strategy in Nigeria cities. Literatures were identified for review through a comprehensive search by using electronic and non-electronic databases. Related published literature and documents were searched in a systematic way using a range of key words relating to climate change vulnerability and adaptation. 
Results: The literature review indicates that adaptation to climate change is hazard specific and factors that determine whether or not adaptation occurs will operate at a variety of scales. The review also indicates that the fight against climate change in our cities could be pursued through three scales: Conurbation/catchment Scale, Neighborhood Scale and Building Scales; using architectural design options. These designs will have additional ecological, biodiversity, recreational, health and flood storage benefits to the environment. 
Conclusion: Reducing climate-induced threats that contribute to environmental degradation, there will be a need to develop an integrated approach at different scales and implement sustainable adaptive strategies using design options.