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Open Access
A hybrid intelligent control model for regulating pH in industrial chemical process
(Federal University of Technology, Owerri, 2022-12) Njoku, Donatus Onyedikachi
This work presented a hybrid intelligent control model for pH regulation in industrial chemical process. The problems of most chemical process are due to the complexities in manipulating non-linear and uncertainty variables. Again, the conventional models used to control processes are prompt to disturbance. The dynamic model approach adopted the first order plus delay time (FOPDT) process transfer function to analyzed the system. The research adopted proportional integral and derivative (PID) and Fuzzy logic system the hybrid compensator model for the developed system. PID model was designed to be tuned in MATLAB window to obtain the variable parameter the Fuzzy Logic system were further integrated with PID to control perturbation and uncertainty among the parameters. The fuzzy logic was designed using Fuzzy Inference System (FIS) in the MATLAB software tool. The gains of the PID algorithm were combined with the Fuzzy Logic system to produce the proposed hybrid intelligent Model called Fuzzy-PID. The model was analyzed in MATLAB/Simulink environment to examine the effectiveness of the hybrid system. Simulation was initially conducted considering loop response of pH system in terms of step input without the addition of the proposed intelligent hybrid model, and the step response shows that the system was not able to reach desired pH set value. A PID controller was simulated in a closed control loop of the pH neutralization process and the step response indicated that the desired pH value was achieved. But the PID control system showed some degree of instability uncertainties. The Fuzzy-PID was implemented as part of the component of the closed loop pH control system and the step response obtained revealed that an improved performance was obtained and the system attained the desired pH value with no instability. The process was modeled in MATLAB/Simulink environment to examine the effectiveness of the hybrid system. The application was developed using JAVA, and Netbean. The work adopted Object Oriented Methodology in the development of the application. Simulation was initially conducted considering loop response of pH system in terms of step input without the addition of the proposed intelligent model. In order to validate the effectiveness of the proposed system, simulations were conducted in acid, neutral and base media with pH setpoint target of 5, 7 and 9 respectively on settling time, rising and overshoot as well the error performance analysis with Integral Absolute Error (IAE), Integral Square Error (ISE) and Integral Time Absolute Error (ITAE). It was observed that less error performance indices were offered by the hybrid model (FPID) control pH neutralization process compared to PID controller in various media –acid, neutral and base. However, the results obtained showed that the proposed hybrid system was able to maintain the setpoint pH values in the various media than individual model,.
Open Access
Alkaline and bacterial pretreatment of rice straw and water hyacinth for biogas production in a batch bioreactor
(Federal University of Technology, Owerri, 2021-06) Hans-Anukam, Uzunma Stephanie
The Presence of lignin in lignocellulosic substrates greatly limits anaerobic digestion for production of biogas. The need for initial pretreatment to sufficiently remove it became inevitable. Alkaline and bacterial pretreatment methods were used to pretreat rice straw and water hyacinth samples for application in biogas production in a batch bioreactor. Optimum concentration of NaOH (%), mass of substrate (g) and duration (h) of the pretreatment were studied using Response surface methodology(Box Behnken design) Bacterial spp isolated from termite gut were identified by 16S rRNA gene sequencing and were used for biological pretreatment of the substrate. Each pretreated sample was co- digested with 1:1, 2:1 and 3:1 ratios of cow dung, pig waste and poultry droppings respectively, as amendments. Optimization studies on the biogas production process from the amendment that gave the highest yield in biogas was carried out. Proximate composition ,lignin, cellulose and hemicellulose content of the feedstock was determined by standard methods as well as microbial succession studies .Results obtained showed that 0.5M concentration of NaOH, 14g of sample and 39.5h exposure time were optimum of NaOH pretreatment of the samples which reduced lignin concentrationfrom17.4% to 8.3% and 17.4 % to 7.3% in bacteria pretreated samples while cellulose, reducing sugar and total sugar contents increased from 10.31% to 38.86%, 6.4%to 6.9% and 156.08%to 167.14%respectively, after chemical pretreatment of water hyacinth samples. Lignin and hemicellulose concentrations reduced from 18.01 % to 7.821 % and 11.01 % to 8.21%, while cellulose concentration increased from 10.31 % to 14.40 % after 30 days of bacterial pretreatment of water hyacinth sample. The 16S RNA gene analysis of bacterial consortium from termite gut indicated the presence of Escherichia coli and Morgenela morganii strain S4L2C (MH745964), with 100%and 98.6%similarity, respectively. There was a significant difference (P ≤ 0.05) in biogas yield in all the Alkaline pretreated rice straw (APRS) and Bacteria pretreated rice straw (BPRS) amended with animal manure compared to APRS, BPRS and URS alone. For NaOH pretreated rice straw, best ratio of rice straw to cow dung was 2:1, which yielded 22.51dm3 of biogas. For bacterial pretreated rice straw, 1:1 ratioof rice straw to cow dung was the best combination, which yielded 27.05dm3 of biogas. For bacterial pretreated water hyacinth co-digested with cow dung, highest yield of biogas was recorded in 1:1ratio, with an average of 12.03dm3. Comparative analysis of biogas yield of APRS with BPRS with amendment at varying ratios gave 30.90% increase in biogas yield for APRS and BPRS with cow dung 2:1,45.45% for BPRS and APRS with cow dung 2:1 and 20.30% for APRS and BPRS with cow dung 3:1APRS/BPRS amended with poultry dropping at1:1,2:1and 3:1 recorded 25.01%,42.01%and19.41% respectively while APRS/BPRS amended with pig waste at 1:1,2:1 and 3:1 recorded1.43%, 3.05% and 16.37%.Result indicated that substrate concentration of 520g, Hydraulic Retention Time 22.57 days and cow dung content of 520 g were the optimum conditions with predicted biogas yield of 1.960 x104 ml for bacterial pretreated rice straw. For NaOH pretreated rice straw, 216.7go substrate at HRT of 15.5 days and 520 g of cow dung as amendment were the optimum conditions, with predicted biogas yield of 1.517 x10 4 ml. Concentrations of components gases in biogas produced by rice straw/ cow dung 2:1 which produced highest volume of biogas in this study, were CO1.149%, CO2 13.556% and CH4 64.960% .proximate characteristics of digestate, such as nitrogen, phosphorus and potassium increased, while others including carbon, total solids and total volatile solid content decreased after anaerobic digestion. Finally, microbial load of slurry during digestion decreased during an aerobic digestion from 0, 14 and 28 days. These prove that rice straw and water hyacinth can be used for large-scale biogas production using Response surface methodology (BBD) from the use of bacterial isolate from termite gut which is significantly more effective in pretreatment than 6% NaOH.
Open Access
Analysis and simulation of salient pole synchronous generator with finite element method and blondel theory to enhance performance
(Federal University of Technology, Owerri, 2022-12) Okon, Paul Edet
Synchronous generators are the only means of converting mechanical energy to electrical energy for bulk electrical power generation. As a result of saturation in its electromagnetic structure, prediction of its performance often involves approximations that seek to account for the effect of saturation. Therefore, it is necessary to develop an accurate method for prediction of the field patterns in magnetic structure to ensure precise performance evaluation. In order to compute the magnetizing reactance of salient-pole synchronous generator apart from using finite element method, a modified winding function approach was developed in this research, which utilize the actual winding distribution and the shape of the pole arc. This research seeks to utilize the finite element variational method (finite element method magnetics) for magnetostatic computation for magnetic field distribution in the air gap for cylindrical and salient-pole type generator. The comparative analysis of the magnetic field distribution is used to illustrate the Two Reaction Theory. The obtained results indicate magneto-motive force comparison of salient 4-pole and cylindrical rotor generator, which clearly demonstrate Andrew Blondel Theory (Two-Reaction Theory). ANSYS Maxwell also is utilized in this research to simulate and analyze salient-pole synchronous generator in order to evaluate the generator performance through electromagnetic field computation. The ANSYS Maxwell results include, moving torque, winding currents, magnetic flux linkages, induced voltages, self and mutual inductances, damper bar voltage/current and others characteristic of synchronous generator under no-load, load and three phase short circuit conditions. The results obtained agreed with the conventional acceptable parameters for the salient-pole synchronous generator.
Open Access
Analysis of crop farmers' vulnerability to soil degradation and adaptation strategies in the Niger Delta States of Nigeria.
(Federal University of Technology, Owerri., 2022-02) Offor, Ijeoma Rose
This study analyzed crop farmers vulnerability to soil degradation and adaptation strategies in the Niger Delta States of Nigeria. The objectives of the study were to examine the socio-economic characteristics of the crop farmers, identify the forms and perceived levels of soil degradation, determine the effect of soil degradation indicators and production factors on the output of dominant staple crops in the study area, ascertain the level of vulnerability of the crop farmers to soil degradation, determine the factors influencing the levels of vulnerability of the crop farmers to shock due to soil degradation in the study area, determine the types and perceived level of adaptation strategies to soil degradation and influencing factors and ascertain the trend in output of major staple crops namely cassava and maize in the study area. Data were collected with a well structured questionnaire from 152 randomly selected farmers. Data were analyzed using descriptive statistics, vulnerability index, multiple regression analysis using ols, ordered probit model, soil degradation index and time trend analysis. Results showed that the mean age of the farmers is 51 years. Results showed that the overall perceived level of soil degradation in the study area is high with a mean of 2.1. The regression result of the effects of soil degradation and production factors on cassava output showed that loss of vegetative cover, decreased soil and water absorption, sub-surface compaction and decline in soil organic matter, labour; planting material, fertilizer and farm size were statistically significant at 1%, while leaching of soil nutrients was significant at 5% level. The regression result of the effects of soil degradation and production factors on maize output showed that loss of vegetative cover, leaching of soil nutrients, sub – surface compaction, decline in soil organic matter, planting material and farm size were statistically significant at 1% level, while the coefficients of labour and fertilizer were significant at 5% level. Result of the vulnerability level of the farmers showed that farmers in the study area are vulnerable to soil degradation with a mean value of 2.09. Results of the ordered probit model show that gender (x1), level of education (x2), age (x3) etc were statistically significant at 1% level, while extension contact (x8) and farming experience (x10) were statistically significant at 5% level, implying that these are the factors influencing the levels of farmers’ vulnerability to soil degradation in the study area. Results also showed that perceived level of adaptation is moderate in the study area with a mean of 2.24. Results of the ordered probit model show that level of education (x2), age (x3), farm income (x5), off – farm income (x6), farm size (x7), farming experience (x10) and nature of soil degradation (x11) were statistically significant at 1% level, implying that these are the socioeconomic factors influencing the levels of farmers adaptation strategies to soil degradation in the study area. The result of the trend of output of cassava and maize in the study area from 1995-2016 revealed that there is fluctuation in both cassava and maize output which can be attributed to the effect of soil degradation. It was recommended that farmers should be motivated to invest their labour and limited financial resources in the use ofadaptation strategies such as soil and water conservation technologies.
Open Access
Analysis of gender equality opportunities and resource use in cereal value chain: Evidence from youth engagement in rice value chain in Sourth-East, Nigeria.
(Federal University of Technology,Owerri, 2023-09) Tim-Ashama, A. C.
The study analyzed gender equity opportunities and resource use in cereal value chain: evidence from youth engagement in rice value chains in Nigeria. it identify the actors and gender roles along rice value chain; examine by gender, the socioeconomic characteristics of actors along the rice value chain; determine the level of gender equity gap in opportunities along the rice value chain; determine the technical efficiency and sources of inefficiency among male and female actors along the rice value chain; determine the value added and the share of the value added by gender along the rice value chain; estimate the factors affecting value added by gender along rice value chain and, identify the constraints to youth engagement in the rice value chain, by gender. A multistage sampling technique was adopted for this study. The sample size consists of 476 youth rice value chain actors randomly selected from 48 villages across three states in South-East Nigeria. The data were collected using questionnaires and analyzed using Modified Gender Equity Index (MGEI), stochastic meta-frontier, value addition and multiple regression models. Descriptive statistics such as frequency, percentages, charts and mean were also used to realize some additional results. Results from MGEI show that the level of gender equity opportunities for youth rice producers, processors and marketers were-0.21,-0.21 and-0.04, respectively, indicating inequity against the female youth. The mean technical efficiency for male and female producers are 0.64 and 0.59, processors 0.70 and 0.69 and marketers 0.52 and 0.61. The determinant factors of technical inefficiency among male and female youth in the study area were level of education, membership of cooperative society, years of experience and access to credit. The overall value-added per tonne by the male youth actors was ₦52,281 and the female youth actor was ₦52,229. The share of the value-added by male youth producers, processors and marketers were 51.65%, 49.41% and 47.78% while the female youth were 48.38%, 50.59% and 52.22%, respectively. Some factors affecting value added by actors in rice value chain were level of education, years of experience, capital invested, information and distance to actor’s node. The major constraints to youth engagement in rice value chain include lack of capital to start up, lack of access to credit, drought, lack of access to better technology, high cost of hiring/operating machines, lack of technical knowhow/skills, and stressful nature of rice value chain. In addition, the female processors added marital challenges and responsibilities as a major challenge while recommends that Policies and interventions that ensure equal access to resources, opportunities, and decision-making power for both male and female youth actors should be implemented through targeted training programmes, awareness campaigns and capacity-building initiatives that promote gender equality. In addition, access to affordable credit and financial services for youth involved in rice value chain should be strengthened through establishment of financial institutions and mechanisms specially targeting youth in agricultural sectors.
Open Access
Analysis of gender equity opportunities and resource use in cereal value chain: Evidence from youth engagement in rice value chain in South-East, Nigeria
(Federal University of Technology, Owerri, 2023-09) Tim-Ashama, Akunna Chinenyenwa
The study analyzed gender equity opportunities and resource use in cereal value chain: evidence from youth engagement in rice value chains in Nigeria. it identify the actors and gender roles along rice value chain; examine by gender, the socioeconomic characteristics of actors along the rice value chain; determine the level of gender equity gap in opportunities along the rice value chain; determine the technical efficiency and sources of inefficiency among male and female actors along the rice value chain; determine the value added and the share of the value added by gender along the rice value chain; estimate the factors affecting value added by gender along rice value chain and, identify the constraints to youth engagement in the rice value chain, by gender. A multistage sampling technique was adopted for this study. The sample size consists of 476 youth rice value chain actors randomly selected from 48 villages across three states in South-East Nigeria. The data were collected using questionnaires and analyzed using Modified Gender Equity Index (MGEI), stochastic meta-frontier, value addition and multiple regression models. Descriptive statistics such as frequency, percentages, charts and mean were also used to realize some additional results. Results from MGEI show that the level of gender equity opportunities for youth rice producers, processors and marketers were -0.21, -0.21 and -0.04, respectively, indicating inequity against the female youth. The mean technical efficiency for male and female producers are 0.64 and 0.59, processors 0.70 and 0.69 and marketers 0.52 and 0.61. The determinant factors of technical inefficiency among male and female youth in the study area were level of education, membership of cooperative society, years of experience and access to credit. The overall value-added per tonne by the male youth actors was ₦52,281 and the female youth actor was ₦52,229. The share of the value-added by male youth producers, processors and marketers were 51.65%, 49.41% and 47.78% while the female youth were 48.38%, 50.59%and 52.22%, respectively. Some factors affecting value added by actors in rice value chain were level of education, years of experience, capital invested, information and distance to actor’s node. The major constraints to youth engagement in rice value chain include lack of capital to start up, lack of access to credit, drought, lack of access to better technology, high cost of hiring/operating machines, lack of technical knowhow/skills, and stressful nature of rice value chain. In addition, the female processors added marital challenges and responsibilities as a major challenge while male marketers included lack of government support as an important challenge. This study recommends that Policies and interventions that ensure equal access to resources, opportunities, and decision-making power for both male and female youth actors should be implemented through targeted training programmes, awareness campaigns and capacity-building initiatives that promote gender equality. In addition, access to affordable credit and financial services for youth involved in rice value chain should be strengthened through establishment of financial institutions and mechanisms specially targeting youth in agricultural sectors.
Open Access
Analysis of scope and economic efficiency in poultry-fish enterprises in Imo State, Nigeria
(Federal University of Technology, Owerri, 2022-02) Opara, Thaddeus C.
This study analysed the scope and economic efficiency of poultry-fish enterprises in Imo State, Nigeria. The specific objectives were to: examine the Socio economic and enterprise characteristics of fish and poultry farmers, estimate cost function from profit function to determine scope efficiency of poultry-fish enterprises, determine how scope and economic efficiency related to the use of specific inputs or the production of specific output, evaluate the determinants of scope efficiency and economic efficiency in poultryfish enterprises in the study area. A multi –stage sampling technique was used to select 210 respondents comprising of 60 fish farmers 60 poultry farmers and 90 joint poultryfish farmers. Structured questionnaire were used to elicit information from respondents while descriptive statistics, inferential statistics. Quadratic regression model, Tobit regression model and analysis of variance were used for data analysis. Findings from the study showed that most of the farmers in the three categories were males, 57.1% for fish, 62.3% for poultry and 66.7% for joint enterprises respectively. Most of the Respondents were between 41 and 60 years age bracket, 65.1% for fish 80.3% for poultry and 58.3 for joint enterprises. The distribution of respondents by marital status showed that most of the farmers were married 80.9% for fish, 75.4% for poultry and 81.9% for joint enterprises. Majority of the respondents had household sizes of 4 to 5 persons, 65.1% for fish, 55.7% for poultry and 63.9% for joint enterprises. 69.8% of fish farmers and 67.2% of poultry farmers had 6 to 10 years farming experience while majority of joint farmers (56.9% had 1-3 years of farming experience. Most sole farmers were small scale farmers 39.7% for fish and 42.6% for poultry while most joint farmers were large scale farmer (75%). The three categories of farmers had poor access to credit with only 19.4 % of joint farmer able to access above N300, 000 credits. In this research, cost functions were recovered from unrestricted profit functions and were used to calculate scope efficiency. The main scope efficiency was 0.025 indicating that the joint production of fish and poultry enterprises reduces total cost by 2.5%. The mean economic efficiencies were 0.72 for fish, 0.68 for poultry and 0.77 for joint enterprises. This indicated that farms could reduce cost by producing at the lowest possible cost. The correlation of scope and economic efficiency with output quantities was positive and significant at 1% level suggesting that the joint production of fish and poultry on the same farm resulted in cost advantage. Also the correlation of scope and economic efficiency with expense ratio were all significant at 1% level which revealed that larger farms tends to have more scope and economic efficiency scores. Again scope and economic efficiency are significantly determined by level of education, farming experience, pond size, and flock size as well as credit amount. It is recommended that educational packages and appropriate training could be necessary to teach farmers those farming practices that encourages cost complementarities and financial institutions should be encouraged to improve on the volumes and terms of loans extended to farmers.
Open Access
Analysis of scope and economic efficiency in poultry-fish enterprises in Imo State, Nigeria
(Federal University of Technology, Owerri, 2022-02) Opara, Thaddeus Chiaka
This study analysed the scope and economic efficiency of poultry-fish enterprises in Imo State, Nigeria. The specific objectives were to: examine the Socio economic and enterprise characteristics of fish and poultry farmers, estimate cost function from profit function to determine scope efficiency of poultry-fish enterprises, determine how scope and economic efficiency related to the use of specific inputs or the production of specific output, evaluate the determinants of scope efficiency and economic efficiency in poultry fish enterprises in the study area. A multi –stage sampling technique was used to select 210 respondents comprising of 60 fish farmers 60 poultry farmers and 90 joint poultry fish farmers. Structured questionnaire were used to elicit information from respondents while descriptive statistics, inferential statistics. Quadratic regression model, Tobit regression model and analysis of variance were used for data analysis. Findings from the study showed that most of the farmers in the three categories were males, 57.1% for fish, 62.3% for poultry and 66.7% for joint enterprises respectively. Most of the Respondents were between 41 and 60 years age bracket, 65.1% for fish 80.3% for poultry and 58.3 for joint enterprises. The distribution of respondents by marital status showed that most of the farmers were married 80.9% for fish, 75.4% for poultry and 81.9% for joint enterprises. Majority of the respondents had household sizes of 4 to 5 persons, 65.1% for fish, 55.7% for poultry and 63.9% for joint enterprises. 69.8% of fish farmers and 67.2% of poultry farmers had 6 to 10 years farming experience while majority of joint farmers (56.9% had 1-3 years of farming experience. Most sole farmers were small scale farmers 39.7% for fish and 42.6% for poultry while most joint farmers were large scale farmer (75%). The three categories of farmers had poor access to credit with only 19.4 % of joint farmer able to access above N300, 000 credits. In this research, cost functions were recovered from unrestricted profit functions and were used to calculate scope efficiency. The main scope efficiency was 0.025 indicating that the joint production of fish and poultry enterprises reduces total cost by 2.5%. The mean economic efficiencies were 0.72 for fish, 0.68 for poultry and 0.77 for joint enterprises. This indicated that farms could reduce cost by producing at the lowest possible cost. The correlation of scope and economic efficiency with output quantities was positive and significant at 1% level suggesting that the joint production of fish and poultry on the same farm resulted in cost advantage. Also the correlation of scope and economic efficiency with expense ratio were all significant at 1% level which revealed that larger farms tends to have more scope and economic efficiency scores. Again scope and economic efficiency are significantly determined by level of education, farming experience, pond size, and flock size as well as credit amount. It is recommended that educational packages and appropriate training could be necessary to teach farmers those farming practices that encourages cost complementarities and financial institutions should be encouraged to improve on the volumes and terms of loans extended to farmers.
Open Access
Analysis of the effects of maritime clusters on hindtherland operations in Nigeria
(Federal University of Technology, Owerri, 2024-03) Nwosu, Emmanuel Nnadozie
The study was carried out to analyze the effects of the performance of selected port-based maritime clusters business components on hinterland operations in Nigeria. The specific objectives of the study were among other things, to determine the determinant maritime cluster business component that contributes significantly to maritime sector Development in Nigeria; to model the effects of maritime cluster development on the shipping export and import capacities in hinterland locations in the six geopolitical zones of Nigeria and the federal Capital Territory, Abuja; and the determine the significant factors influencing the decision of maritime and allied firms, to locate operational basis in port-based maritime clusters in Nigeria. The study used a mixed research design method in which both survey methods involving the use of primary data sourced through the use of questionnaire as survey instrument, and quantitative research methods which involved the use of time series quantitative data on the shipping export and import capacities of each of the hinterland zones in the six geopolitical zones of Nigeria were sourced from the Nigeria ports Authority Statistical reports, covering a time period of 19 years, were used. The statistical methods of principal component factor analysis (PCFA) and the log-linear multiple regression analysis were used to analyze the data obtained. The findings of the study indicate that the offshore oil and gas maritime-cluster business component has Eigen values greater than 1 (5.904>1) and constitute the determinant maritime-cluster business component that significantly contribute to the development of the maritime sector in Nigeria over the years. The findings of the study also indicate that there is significant relationship between maritime-cluster development and the shipping export and import capacities of hinterland regions in the six geopolitical zones of Nigeria. The result however indicate that, the North-East and Federal Capital territory hinterland regions each recorded zero shipping export operations over the period covered in the study. The findings of the study further reveal that the significant factors that contributes to the decision of firms to locate investments in maritime clusters in Nigeria include: Guaranteed security of investment, Favourable Government policy, The ease of administration and coordination of the business divisions of a firm from the cluster location, Reduced labour cost and access to professionals and Access to transport cum optimization of logistics and production cost, with each having Eigen values of 2.992, 2.244, 1p.241, 1.145, and 1.039. the policy implications of the findings were also discussed. It was recommended that, Government policies such as policies creating free trade zones in maritime regions and tax exemptions for new firms should be used to attract more maritime firms to locate in port-based maritime clusters in Nigeria. The significant relationship between maritime sector development, export and import capabilities of hinterlands in Nigeria, suggest that the hinterlands can guarantee the achievement of higher output in the maritime sector if necessary investment is made by Government to improve the shipping export and import trade potentials of the hinterlands.
Open Access
Application of some metal oxide nanoparticles for the removal of heavy metals from wastewater
(Federal University of Technology, Owerri, 2024-12) Igwe, Prince Uche
The present work involves the study of the removal of As3+, Cd2+, Cr6+, Ni2+ and Pb2+ from synthetic wastewater solutions using metal oxide nanoparticles. Laboratory experiments were used to investigate the efficiency of adsorbents in the uptake of heavy metals from industrial wastewater. These include equilibrium tests and kinetic studies. The physical and chemical characterization of the metal oxide nanoparticles was carried out using different analytical techniques such as Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X – Ray Diffraction (XRD), X – Ray Fluorescence (XRF), and Fourier Transform Infrared (FT-IR) Spectroscopy. The kinetic study indicated the suitability of the modified nanoparticles for the removal of As3+, Cd2+, Cr6+, Ni2+ and Pb2+ ions from synthetic wastewater. Column experiments were used to identify the effect of parameters that affect the rate of adsorption such as the effect of contact time, the effect of adsorbeThis nt mass, effect of initial solution concentration, and the effect of temperature and evaluated their impact on the efficiency of modified and its control of the metal oxide nanoparticles in the removal of heavy metals from industrial wastewater. The kinetic studies showed that the capacity of the adsorbents for the removal of heavy metals increased with contact time, increased with a greater mass of absorbent, higher solution concentration as well as the solution temperature. The results from the equilibrium studies positively demonstrated that metal oxide nanoparticles synthesized modified and nonmodified can be used as an excellent adsorbent for removing heavy metals from wastewater solutions. The equilibrium experiments indicated that the capacities of metal oxide nanoparticles for the uptake of heavy metals increased when the adsorbent mass increased. The results indicated that the maximum removal capacities Q were 67.11, 67.11, 54.05, 55.56 and 84.74 mg/g of modified and its control of the metal oxide nanoparticles for Arsenic, cadmium, chromium nickel and lead respectively. the Langmuir, Freundlich and Temkin isotherm models were used to characterize the experimental data and to assess the adsorption behaviour of modified and its control of the metal oxide nanoparticles for arsenic, cadmium, chromium nickel and lead. The experimental data were slightly better suited to the Langmuir isotherm than the Freundlich isotherm. The value of the correlation coefficients R 2 ranged from 0.93 to 0.99 for the Langmuir isotherm and from 0.90 to 0.99 for the Freundlich isotherm. The results indicate that starch modified metal oxide nano adsorbents showed higher adsorption. Therefore, starch modified nanoparticle or adsorbents should be incorporated in the synthesis of metal oxides used as adsorbents, due to its ability to improve the surface area and enhance greater adsorption of metal ions.
Open Access
Assessment of commercial agriculture development project (CADP) for maize value chain in Nigeria
(Federal University of Technology, Owerri, 2023-10) Oshaji, Ifedayo Oluwakemi
This study assessed the Commercial Agriculture Development Project (CADP) for Maize ValueChain in Nigeria. The specific objectives of the study were to: assess the level of gender involvement and segmentation supported by the project in the targeted value chain; assess the performanceof CADP relative to baseline in terms of Commodity Interest Groups’ (CIGs) technology adequacyanddemographic variables, assess the performance of maize value chain relative to baseline production, processing and sales, estimate the socioeconomic factors of the commodity interest groups that influence the production, processing and sales performance of the targeted value chain; estimatetheinstitutional and socioeconomic factors that af ect the availability of CADP’s matching grant tocommodity interest group in maize value chain; and examine the factors constrainingtheimplementation of CADP along maize value chain. A multi-stage sampling technique was usedintheselection of sample for this study. Data were collected from 360 maize farmers. Data collectedwereanalyzed using descriptive statistics, functional analytical tool, Duncan Dissimilarity Index (DDI), performance index, multivariate regression technique, multivariate probit model and principal component analysis. The result revealed that the male producers had the highest percentage (17%)of capital inadequacy which invariably af ected the rate of returns. The pooled data of the maizeprocessors showed that 59.6% of the respondents were male while 40.4%were female indicatingthat the males were more involved in maize processing than their female counterpart in the studyarea, which is not so in other studies. This could be attributed to the customs and tradition as well asthe insecurity in the study area. The pooled result of the level of dissimilarity index showed that the female actors in the study area dominated in the area of capital disbursed and output. This meansthat 1.21% of capital disbursed and 1.872% of output favored the females than their malecounterparts. This result means that the female actors are more capital adequate and this could bebecause the females are making more ef ort in adding capital from external sources which positivelyafects their output. The result further revealed that value added to maize products can significantly enhance sales performance by 2.98 X 10 -08 . The average total variable costs incurred onmaizeproduction in the study was N283,651.06 while the total revenue realized was N619,447.61whichindicates that maize production is a profitable farm enterprise. The result also showed that thenet farm income of the farmers is significant and positive (0.0001), hence increase in their farmincomewill make them comply with the sharing formula and provide their matching grant as soon as there is need for it in maize value chain activities. There was improvement in the technology adequacyinthe study area: the pooled data showed that the technology adequacy in the base year was 47.7%and 58.3% in the current year. The pooled result further showed that performance in processing and marketing/sales outran the baseline by 104.88% and 120.82% respectively. The Principal Component Analysis (PCA) extracted 6 major factors constraining the implementation of CADP in the value chain namely: delay in fund disbursement, insuficient access to fair market priceinformation, inability to provide percentage requirement for the fund, funding do not obey the sharing, land tenure problem and poor infrastructure (roads, irrigation, poor harvest facilities). The Federal and State government should improve the infrastructural facilities especially theroadnetworks to serve as an incentive to rural farmers to work harder to increase productivity, subsequently increasing income and reducing the length of time products take to get to the final consumers there by reducing spoilage as well as wastage.
Open Access
Assessment of Jatropha curcas L. as alternative nematicide in controlling root-knot nematode disease of Okra for improved yield
(Federal University of Technology, Owerri, 2022-01) Ogwudire, Ezechukwu Vincent
The assessment of Jatropha curcas L. as alternative nematicide in controlling root-knot nematode (Meloidogyne incognita) disease on Okra for improved yield was conducted in ultisols of Owerri, Nigeria. These were in 2016 and 2017 cropping seasons at the teaching and research farms of Federal University of Technology Owerri. Jatropha curcas L. cultivars; Cv ‘Illorin’, Cv ‘Kwara’ and Cv ‘Ihiagwa’ were first screened in a potted experiment for susceptibility to Meloidogyne incognita naturally endemic in the area using scoring index. Results on root-knot assessment showed no root-knot infection in either of the cultivars tested. Phytochemical investigations carried out for a Plant Based Nematicide revealed the presence of Alkaloids, Saponins, Flavonoids and Tannins in the Seeds, Roots and Leaves respectively. Laboratory test for nematicidal properties against hatchability and mortality of M. incognita was conducted using a 3x4x4 factorial experiment fitted in Completely Randomized Design with three replications. Alkaloids, Saponins, Flavonoids and Tannins applied at 0, 5 and 10 mls per thirty Juveniles (J2) for mortality and twenty egg masses for hatchability were suspended in 10 mls of distilled water respectively. Petri dishes were kept at ambient temperature after 12, 24, 48, and 72 h incubation. Results show that at 10 mls, Seed Alkaloids recorded highest mortality (99.73 %) after 72 h treatment exposure while at 5 mls, Root Alkaloids recorded highest mortality (94.73 %) after 72 h treatment exposure. Most egg hatchability reduction (0.00 i.e 100%) was achieved with Seed Saponin after 12 h treatment exposure time at 10 mls, while at 5 mls (0.08) egg hatchability reduction was achieved with Seed Saponins after 12 h treatment exposure time. Individual Plant based nematicides were further evaluated for their effects on root-gall nematode susceptible Okra variety “NHAe47-4”. Four independent 3x6 factorial experiments arranged in Completely Randomized Design with five replications were conducted in the screen house. Each nematicidal extract was applied at 0,1,2,3,4, and 5 mls, and Jatropha parts with three levelsseed, root and leaves. Results showed that all plant based nematicides applied at 5 mls/pot significantly (p<0.05) reduced root-galls and increased the growth, yield, mucilaginous property, and nutritional composition of okra. This was particularly with Leaf Tannins application which increased pod weight by 67 % and 61 % over control at 4.88 g and 5.11 g in 2016 and 2017 respectively. This was followed by Root and Seed Alkaloids which increased pod weight to 4.02 g & 4.26 g indicating 71 % and 67 % increase over control in 2016 and 2017 respectively. Seed and leaf Saponins increased pod weight to 3.62 g & 3.84 g indicating 58 % & 51 % increase over control in 2016 and 2017 respectively. Seed and Leaf Flavonoids increased pod weight to 3.56 g & 3.80 g indicating 75 % & 71 % increase over control in 2016 and 2017 respectively. Correlation analysis showed that root-knot nematode correlated negatively with growth and yield parameters of Okra. Nematicidal extracts of Jatropha curcas and plant parts at the respective rates/levels-controlled root-knot nematode (Meloidogyne incognita) infection on okra, enhanced the pod weights, Mucilaginous property and nutritional composition of okra and are therefore recommended for use in Okra production.
Open Access
Assessment of quality of some community's water, sanitation, hygiene practicies and occurrence of water-borne infections among residents in Imo State
(Federal University of Technology, Owerri, 2024-08) Nnoli, Matthew Chuks
A total of 920 residents participated in this study. Largest age grade used was 31-40 years (33.7%), followed by 41-50 which is 214 (23.3%), those less than twenty years were 102 (11.1%). About 600 (65.2%) attained tertiary education, 24% attained secondary education while 6.5% and 4.3% attained primary and non-formal education respectively. 408 (44.3%) were civil servants, 114 (12.4) were artisan, and ½ of the residents earned 21,000 (25.7%). Common sources of drinking water are Spring 38.1%, borehole36.1% and lake/stream 0.4%. 240 (26.1%) of residents had distance to source of water <_ 100 meters and 132 (14.3%) had their distance > 1km. Major water fetchers were children under 15 years; adult female was 202 (22%). 580 (63.1%) do not treat their water, but 326 (35.4%) do treat – 254 (77.9%) use boiling, 30 (9.2%) use alum and clot, 12 (3.7%) do chlorination. 812 (88.3%) store water – 420 (51.7%) stores in plastic bucket/drum, 180 (22.3%) use Geepee and 140 (17.2%) use earth pot. For awareness of WASH protocols, 862 (93.7%) stated Yes, while 32 (3.4%) stated No: 426 (53.4%) knew through schools, 196(24.6%) via radio, 100 (12.5%) via tv and 8 (1.0%) through posters. The aware (83.8%) suffered from WASH-related infections and the unaware (94.5%) suffered too but the difference between these two groups is significant at 5% level (p<0.001, x2 = 13.570). 492 (53.5%) use water cistern toilet, 216 (23.5%) use latrines while 126 (13.7%) use pour flush latrines. 392 (42.6%) use tissue paper to clean after toilet use, 97% use tissue paper and water, 158 (17.2%) use paper, 94 (10.2%) use tissue paper, water and soap. 874 (95%) wash hand after toilet use while 22 (2.4%) do not. 620 (71.6%) use water and soap to wash hand after toilet use, 246 (28.4%) use water only. 536 (58.3%) have functional toilet: 216 (23.5%) toilet is provided by the age grade, 150 (16/3%) by individuals, and 78 (8.5%) by the government. 812 (88.3%) said proper excreta disposal improves community health, 70 respondents said no. 356 (38.7%) clean toilets weekly, 316 (34.3%) on daily basis and 122 (13.3%) on monthly basis. 882 (95.9%) are aware of hygiene protocols, 38 (4.1%) not aware: 694 (75.4%) use water and soap for hand cleaning, 188 (20.4%) use water only, 16 (1.7%) use detergents while 8 (1%) use water, ash and others. 6 (0.7%) use all methods. 232 (25.2%) wash hands before cooking, 228 (24.8%) wash hands when dirty, 202 (22.0%) wash hands after eating, 8 (0.9%) wash hands after cleaning baby’s bottom. 714 (77.6%) bathes twice daily, 190 (20.7%) bathes once daily, 16 (1.7%) bathe twice weekly. Hygiene practice reduce water-borne infections – 876 (95.2%) said Yes while 38 (4.1%) said No, Bacteria found in the study area are Enterococcus faecalis 15%, Klebsiella pneumonia 9%, Staph. Aureus, Bacillus cereus and Pseudomonas aeruginosa 8% each. 80 (8.7%) defecate in stream and trenches, 40 (4.3%) defecate in bushes and polyethene bags. 818 (88.9%) were aware that open defecation leads to disease. Cholera, skin infection, diarrhea, typhoid and malaria were WASH- related infections found.
Open Access
Assessment of streamflow relationship models of selected rivers in Southern Nigeria
(Federal University of Technology, Owerri, 2023-10) Uzoukwu, Regina Akudo
This study focused on Assessment of Streamflow Relationship Models of Selected Rivers in Southern Nigeria. The rivers include; Cross River, River Niger, Owena River, Owan River, Ikpoba River, Ossiomo River and Imo River. Statistical methods of least squares (regression analysis) were used to develop streamflow mathematical models (Power model, Polynomial model and Analysis of Variance (ANOVA) model for regression) of the selected rivers. Models performance in calibration and verification were evaluated by means of coefficients of determination, coefficients of correlation, Nash– Sutcliffe model efficiency, mean absolute relative error, percentage bias, root mean square error or standard error of estimate and mean of residues or mean absolute error. Verification results exhibited a similar pattern in model performance to the calibration results, indicating that the models have good curve fitting. Comparisons of the streamflow models were carried out using One-way ANOVA F-Test, Variance Ratio Test or Snedecor’s F-distribution (F-Test). Further comparisons using graphs and a final comparison using Student’s t-Test were done. The models developed will serve useful purposes in the design of dams, estimation of the sizes of reservoirs, public water supply, flood control and hydropower generation, pisciculture, recreation, irrigation, wild life protection, water sports and tourism thus ushering in an era of socio-economic and industrial development for the Southern Nigeria. This research will play an important role in ensuring that water resources management processes in the Southern Nigeria are scientifically based and efficiently used so as to satisfy the needs of both natural systems and humanity, as being demonstrated in the applications of the calibrated models.
Open Access
Assessment of streamflow relationship models of selected rivers in southern Nigeria.
(Federal University of Technology, Owerri, 2023-10) Uzoukwu, Regina Akudo
This study focused on Assessment of Streamflow Relationship Models of Selected Rivers in Southern Nigeria. The rivers include; Cross River, River Niger, Owena River, Owan River, Ikpoba River, Ossiomo River and Imo River. Statistical methods of least squares (regression analysis) were used to develop streamflow mathematical models (Power model, Polynomial model and Analysis of Variance (ANOVA) model for regression) of the selected rivers. Models performance in calibration and verification were evaluated by means of coefficients of determination, coefficients of correlation, NashSutcliffe model efficiency, mean absolute relative error, percentage bias, root mean square error or standard error of estimate andmean of residuesor mean absolute error. Verification results exhibited a similar pattern in model performance to the calibration results, indicating that the models have good curve fitting. Comparisons of the streamflow models were carried out using One-way ANOVA F-Test, Variance Ratio Test or Snedecor’s F-distribution (F-Test). Further comparisons using graphs and a final comparison using Student’s t-Test were done. The models developed will serve useful purposes in the design of dams, estimation of the sizes of reservoirs, public water supply, flood control and hydropower generation, pisciculture, recreation, irrigation, wild life protection, water sports and tourism thus ushering in an era of socio-economic and industrial development for the Southern Nigeria. This research will play an important role in ensuring that water resources management processes in the Southern Nigeria are scientifically based and efficiently used so as to satisfy the needs of both natural systems and humanity, as being demonstrated in the applications of the calibrated models
Open Access
Assessment of the bacteriological qualities of meat and contact surfaces in markets in Abia State, Nigeria
(Federal University of Technology, Owerri, 2023-09) Iwuagwu, Uchechukwu Olive
Microbial contamination of meat comes from several sources including during cutting, handling and processing of the meat. This study was carried out to determine the sanitation and hygiene practices of meat handlers and assess the bacteriological qualities of meat and contact surfaces in markets in Abia State, Nigeria. This research involved the use of Hazard Analysis Critical Control Point (HACCP) checklist and Walk-through inspection to determine the sanitation and hygiene practices of meat handlers. Also, microbiological analyses of red and white meat; water and contact surfaces were used to determine the microbial qualities of the environmental media. A total of 425 meat samples were randomly collected from 425 meat handlers in Abia State. Furthermore, seventy eighty (78) samples comprising twenty (20) water samples and fifty eight (58) swabs from meat contact surfaces were used to establish the bacteriological quality of the water samples and meat contact surfaces. The multistage simple random sampling technique through balloting was employed to determine communities/markets for the study. Samples for the study were collected and analyzed using standard microbiological techniques such as culturing; and the bacteria were enumerated and identified using biochemical tests. Results showed that the total mean percentage score for the harmonized HACCP checklist was 24.66 ±n6.08% and falls far below the HACCP Good Hygiene Practices (SOPs) minimal pass mark of 40%. At critical control points, the mean percentage HACCP scores were 22.51 ± 4.70% for meat transportation; 20.99 ± 5.87% for meat storage; 27.97 ± 5.30% for personal hygiene; 26.30 ± 5.65% for cleaning and sanitation; 20.44 ± 4.81% for pest control; 26.13 ± 5.09% for waste disposal and 21.58 ± 4.89% for staff competency and training. 87.00% of the meat samples analysed using nutrient agar had bacterial growth. The mean bacterial loads of the red and white meat samples on nutrient agar plates were 2.33 x 106 , 1.99 x105 and 2.73 x105 cfu/g; and 1.81 x 105 , 1.73 x 105 and 2.20 x 106 cfu/g for Umuahia, Aba and Ohafia zones respectively. The prevalent bacterial isolates include Staphylococcus sp (78.80%), Bacillus sp (73.17%), Enterococcus sp (64.00%), Escherichia coli (62.11%), Salmonella sp (62.11%), Klebsiella sp (51.29%), Micrococcus sp (44.94%) and Campylobacter sp (43.52%). SPSS analysis using the one way ANOVA showed no significant difference (P>0.05) in bacteria isolated from markets in the three Senatorial Zones of the State. Staphylococcus sp was isolated in 61.11% of the tables, 50.00% of vehicles, 41.67% of knives and 46.32% of water; Salmonella sp was isolated in 47.22% of the tables, 36.11% of vehicles, 30.56% of knives and 43.85% of water; Bacillus sp was isolated in 41.67% of the tables, 44.44% of vehicles, 33.33% of knives and 23.70% of water; Campylobacter sp was isolated in 27.78% of the tables, 25.00% of vehicles, 30.56% of knives and none in water. There was no significant difference (P>0.05) in bacteria isolated from the contact surfaces and water from the markets in the three zones of the State. The poor HACCP compliance in meat handling (during transportation, storage, personal hygiene and sanitation practices etc) as observed in this study and indicated by the low mean percentage HACCP checklists score of 24.66 ± 6.08% could have contributed in the contamination of the meat carcasses resulting in the observed high mean bacterial loads from the meat samples. Thus, the bacteriological quality of meat in markets in Abia State could be said to be poor due to the recorded high mean bacterial load counts and the isolation of Indicator bacteria such as E, coli, Salmonella and Campylobacter from the studied meat samples. The presence of E. coli in the studied meat samples is an indicator of feacal contamination and a red alert for the Public health sector. It is recommended among others that meat should be properly cooked before consumption; and meat handlers should undergo proper training and regularly update their knowledge of meat safety.
Open Access
Assessment of the impact of concessioning on the productivity of Nigerian Ports
(Federal University of Technology, Owerri, 2019-02) Nze, Obiageli Nneka
This study assessed the productivity of Nigerian ports. The study adopted ex post facto design. Using ship traffic, vehicle traffic, berth efficiency, turnaround time as input explanatory variables and output factors as average throughput to compare the pre concession and post concession. The six Nigerian ports: Tincan Island Ports, Apapa Port, Port of Delta Warri, Calabar Port, Rivers Port and Onne Port were sampled. A survey was conducted on 50 stakeholders in the port sector to determine the factors contribute to port’s productivity. These factors were examined for each of the ports under study and were analysed with t-test using a hypothesized mean. Secondary data was extracted from National Bureau of Statistics (NBS) Annual Reports, Nigeria Port Authority (NPA) Annual Reports, and Central Bank of Nigeria (CBN) Annual reports.From the t-test, the factors with p-value less than 0.05 were the significant ones. Among the factors influencing the productivity of the ports in Nigeria are predetermined operational problems, frequent congestion of ship, poor inboard services and high cost of documentation etc. Using Data Envelopment Analysis as the fundamental analytical tool to test the most efficient port before and after the concession period. The result reveals that Onne Port and Tin Can Island Port productivity increased significantly after the concession. However, Rivers, Delta, Calabar and Apapa Ports experienced unstable efficiencies in the post concession era. The implication is that concession of Nigerian Ports have favourable effect on Onne Port and Tin Can Island Port and less favourable to Rivers, Delta, Calabar and Apapa Ports. In line with the result, it was recommended that since it was observed that there was element of improvement in the post-concession period of operation at Nigerian Ports, we recommend adequate provision of superstructure for the private operators to utilized them and compliment their infrastructure with them towards the achievement of goals of concession. However, concessioning is a good instrument to improve productivity in Nigerian Ports and requires continuity among Nigeria Ports. We recommend adequate and necessary cargo handling equipment at Ports that experienced fluctuating efficiency.
Open Access
Biochemical and carcinogenic effects of monosodium glutate and soya bean in wistar rats
(Federal University of Technology, Owerri, 2021-07) Bob Chile-Agada, Adaeze
This study was carried out to investigate the biochemical effects of short, medium and long term administration of monosodium glutamate (MSG) and soya beans in both male and female Wistar rats, using standard methods. LD50 was carried out using rats which led to the choice of 1000, 2000 and 3000 mg/kg b.w for low, medium, and high doses of the samples. A total of 210 (105 males and 105 females) weanly Wistar rats weighing 70 – 78g were divided equally into three groups of 70 rats each representing the various experimental durations (2, 4, and 6 months). Each of these groups containing 70 rats was further divided equally into 14 subgroups, each containing 5 rats. Group 1 and 8 were controls for female and male rats fed normal raw chow and saline. Groups 2-7 (female rats) and 9-14 (male rats) were rats administered low dose (LD), medium dose (MD) and high dose (HD) MSG and soya beans respectively. 6-o-Malonylgenistin (98.47%) and Glycitin (98.11%) were the most abundant oestrogen-like compounds in the dehulled and oil of soya beans. The glucose and insulin levels of both male and female rats were significantly altered by HDs of both MSG and soya beans after 6 months while ALT, ALP and AST levels were significantly elevated after 4 and 6 months following administration of both MSG and soya beans and were more extensive in HD soya bean fed rats. No significant changes (P> 0.05) were observed in the urea levels after 2 and 4 months soya beans respective administration to female and male rats, while HD MSG significantly elevated the creatinine levels of male and female rats after 4 and 6 months administration. Administration of soya beans and MSG for 2 and 4 months had no significant effect (P > 0.05) on the bicarbonate and chloride levels. The HDL levels were significantly reduced while LDL, TC, and TG were significantly (P < 0.05) elevated after 6months HD administration of MSG and soya beans. Soya beans administration produced no significant change in the SOD levels for female rats and catalase levels in male rats after 2 months administration whereas the MD and HD administration of MSG significantly elevated MDA levels of both male and female rats after 4 and 6 months. Two and four months administration of soya beans and MSG produced no significant changes (P > 0.05) in the LH and FSH of female rats while MD and HD of MSG and soyabean significantly decreased the testosterone and LH of male rats. The colorectal, pancreatic, and ovarian cancer markers, and prostate specific antigen levels were significantly elevated after administration of MD and HD of MSG for 2, 4, and 6 months. This study has shown that the high dose administration of monosodium glutamate and soya bean produced delecterious effects on the biochemical parameters and cancer markers on rats after six months extensive administration.
Open Access
Biochemical and histopathological studies of posible co-morbidity of cadmium, chromium and lead in albino rats
(Federal University of Technology, Owerri, 2023-09) Osoh, Kennedy
Cadmium, chromium and lead are known environmental pollutants that induce toxicity in living organisms when exposed to them. The risk assessment of Cd, Cr and Pb is done individually while in reality living organisms are exposed to them jointly as they co-occur in the environment, food or water. This study was aimed at investigating their possible co-morbidity through biochemical and histopathological evaluations of albino rats exposed to them simultaneously. Seventy male albino rats were used in the study. Specified doses of 5, 10, and 20mg/kg body weight respectively, of these pollutants/metals were administered by gavage thrice weekly to 60 albino rats and 10 albino rats were used as control. There were four treatment groups Cd, Cr, Pb and Cd+Cr+Pb (i.e. Cd alone, Cr alone, Pb alone and Cd, Cr, Pb combined) per dose with five animals per treatment group. The treatments were for 90 days, and salt solutions of the metals (i.e. CdSO4, K2Cr2O7, and Pb(NO3)2) were used while the control received only distilled water. Body weights (BW) of the rats were measured and percentage BW gains of the rats were calculated. The animals were sacrificed after 90 days and blood samples were analyzed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), total bilirubin, urea, creatinine, potassium (K), chloride (Cl), inorganic phosphorus, malondialdehyde (MDA), reduced glutathione (GSH), ascorbic acid, superoxide dismutase (SOD), catalase (CAT), haemoglobin (Hb), packed cell volume (PCV), white blood cell (total) (WBC[T]), and red blood cell (RBC). Organ (liver, kidney, & heart) to BW ratio were measured. Histopathological evaluations of liver, kidney, and heart were done. Results of combined treatment showed hormetic response with regard to ALT, AST, total bilirubin, and urea as they were elevated in the low dose but decreased with high dose. This phenomenon was also observed in Cr individual treatment except in total bilirubin. The results showed that ALP, LDH, K, and inorganic phosphorus levels in the combined treatment group increased with increasing dose but was not significantly different (p>0.05) from that of the most hazardous metal in the individual treatments. Oxidative stress was observed in both the combined and individual treatments as MDA increased while GSH and ascorbic acid were reduced with increasing dose. SOD and CAT increased with increasing dose hence reducing the impact of the oxidative stress as observed. Less-than-additive interaction was observed in the 5mg/kg treatment group among the mixture components with regard to Hb and WBC. Combined treatment with the metals caused significant decrease in percentage BW gain but was not significantly different (p>0.05) from that of the most hazardous metal in the individual treatments. Histopathological evaluation showed tissue injury in liver and kidney in the 20mg/kg combined and individual treatment groups only probably due to high dose. Mortality was observed in the course of the study as two animals died due to the combined treatment (i.e. one at 10mg/kg group and one at 20mg/kg group) while three animals died due to the individual treatments (i.e. one at 10mg/kg Cd group, one at 20mg/kg Cr group and one at 20mg/kg Pb group). Conclusively, the results suggested that there was no significant health risk posed by simultaneous exposure to the metals beyond the risk already posed by the most hazardous individual metal for the endpoint of interest. Interactions where they occurred were predominantly less-than additive. Hormesis should be considered in their risk assessment. The concept of effect addition (independent action) over-estimated the risk due to the combined treatments.
Open Access
Bioremediation of crude oil and heavy metals polluted soil with constructed wetland system
(Federal University of Technology, Owerri, 2024-11) Ikeanumba, Michael Okwudiri
The preliminary part of this study was carried out to determine the tolerance limit of eight (8) eight native plant species in soil polluted with crude oil (3%, 7%, and 10% concentrations) and fixed levels of heavy metals (Zn: 39.4 mg/L, Ni: 10.2 mg/L, Cu: 29.4 mg/L, Pb: 11.2 mg/L). The selected plants—Brachiaria distachyoides Stapf, Paspalum conjugatum P.J. Bergius, Cyperus dichrostachyus Hochst. ex A. Rich., Kalanchoe pinnata (Lam.) Pers., Panicum maximum Jacq., Mimosa pudica L., Mariscus ligularis L., and Mariscus rotundus—were sourced from crude oilimpacted sites.Results showed that Paspalum conjugatum P.J. Bergiusgave the best result, thriving in 10% crude oil and heavy metal-contaminated soil for five months followed byMariscus ligularis L. and Brachiaria distachyoides Stapfwhich survived for 30 days under the same conditions. Other species were only able to tolerate 7% crude oil heavy metals. Toxicology studies of amendments revealed that a 1% native soap solution provided optimal growth stimulation for hydrocarbon-utilizing microorganisms (bacteria and fungi), followed by 1% poultry manure and a 1% combination of both. This was followed by 10%, while higher amendment concentrations of 30% significantly inhibited microbial growth.The study shows the effectiveness of hybrid constructed wetlands for the remediation of soil and water polluted with crude oil and heavy metals. Microbial analysis identified Pseudomonas xiamenensis, Acinetobacter baumannii, Alcaligenes cloacae, Enterobacter cloacae, Pantoea dispersa, Lysinibacillus fusiformis, and Kocuria palustris as hydrocarbon-degrading bacterial species in the soil. Among these, Pseudomonas xiamenensis was the most prolific biosurfactant producer, while the others showed moderate production levels.These findings provide valuable insights into the development of sustainable strategies for bioremediation of crude oil and heavy metal-polluted soils.