| 1 |
Author(s):
Ibrahim Salau, Hannatu Muhammad Lawal.
Page No : 1-9
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Comparison of Two Storage Techniques on the Nutritional Composition of Onion Bulbs.
Abstract
Onion (Allium cepa L.) has been valued as a food and medicinal plant since ancient times. It is widely cultivated, second only to tomato, and is a vegetable bulb crop known to most cultures and consumed worldwide. This study investigated the effects of two (2) storage techniques on nutritional composition of onion bulbs. During storage periods, the onion bulbs are deteriorated due to rotting, sprouting, black mold and physiological loss in weight, which have been a major problem for the onion growers. The result of onion bulb after storage at wooden platform shows the highest content of moisture (33.30% ± 1.24) followed by crude protein (23.62%± 0.53), crude fiber had (15%± 0.67), ash content (10.60% ± 0.63) and the lowest was obtained in the crude lipid (10% ± 0.68). The result of the proximate analysis indicated that the moisture content significantly deferred between the fresh bulbs (35%) and the stored samples with a cemented floor having the lowest moisture content of (20%). The loss of moisture from the bulbs during storage could be because the bulbs were stored in a dry and aerated environment that could subject the bulbs to loss water. The losses in the onion bulbs may be reduced to a certain level through opposite storage methods. From the research, it could be concluded that wooden platform on the floor is the best method of storage for onion bulbs.
| 2 |
Author(s):
Chukwuka Ernest Jebolise (Ph.D.), Glory Ewere Chukwuka.
Page No : 10-19
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Entrepreneurial Microbiology: A Perspective of Microbiology for Wealth Creation.
Abstract
This research paper frantically inquired to ascertain the entrepreneurial potential of Microbiology for wealth creation and poverty reduction. This study adopted a qualitative research methodology through the extant and systematic, exploratory review of literature to carry out this study which is modified to understand the motivations, viewpoints, theories and views of scholars in order to address the study issue. This study relied on secondary source of data. This study revealed that there are many chances for innovation and expansion when microbiology is pursued as a business or an Entrepreneurship. Infectious illnesses, food safety, environmental pollution, and renewable energy are some of the most urgent issues confronting society today. The paper found that the worldwide market for microbial goods, estimated at USD 160 billion in 2022, grew at a compound annual growth rate (CAGR) of 6% between 2023 and 2033. The sector is expected to grow to be worth USD 286.53 billion by 2033. Entrepreneurs in this industry are creating new goods and technology to solve these issues. The study discovered that Entrepreneurial Microbiology has the potential to have a big social and economic effect on the globe with the correct funding and assistance. The study concludes that Entrepreneurial Microbiology has the potential for wealth creation through the increase in demands for microbial goods and biotechnology. The study recommends a more robust top-level Microbiology and biotechnology design and implementation within the entrepreneurial ecosystem for wealth creation and poverty reduction, as well as economic development of Nigeria. Microbiologist should develop entrepreneurial mindset and culture in opportunity identification and economic exploitation of such business opportunities for self-sufficiency and self-actualization.
| 3 |
Author(s):
Nwawuike I. M., Mmadufor J. C., Eches E. E., Nwawuike N..
Page No : 20-29
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Spatial Distribution of Cadmium and Lead (Cd and Pb) Along Owerri – Orlu Road Highway in Imo State, Nigeria.
Abstract
Vehicular emissions have been found to constitute the major sources of soil and air pollution. This study attempts to investigate the spatial influence of vehicular emissions on the accumulation of heavy metals (cadmium and lead) in some of the roadside soil of Owerri – Orlu road in Imo state. Four locations were selected on the basis of their high concentration of vehicular traffic in Owerri – Orlu. They include Y- Junction, Umuaka, Okwudor and Amaifeke. The concentrations of two heavy metals (Cadium and Lead) in the soil samples were determined calorimetrically using atomic absorption spectrophotometer (AAS). The heavy metal (Cd and Pb) results obtained indicate that the metals from the four sampled sites showed high concentration of Cd far above the soil permissible limit (3 mg kg-1) on all the sampled sites which farther increase away from the road. The concentration of the Pb was found to be lower than the soil permissible limit (50 mg kg-1). Pb despite been lower than the permissible limit, also follows the same trend as in Cd. A factor strongly controlled by the soil properties especially soil texture which are mainly of high sand particles (86.3 to 91%). Correlation results showed that soil properties heavily influence the amount and the movement of these metals along the road and farther away from the road. Although Pb concentrations were below permissible soil limit long time exposure may pose health hazards. The enhancement of fuel quality and the adoption of emission standards to mitigate the impact of vehicular emissions on human health should be adopted.
| 4 |
Author(s):
Azibalua Onyagholo PhD.
Page No : 30-40
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An Anthropocentric Approach to Christian Religion, Forest, Environmental Conservation and Climate Change in Kolo Creek.
Abstract
This study tries to examine anthropocentricism as an environmental ethical theory which is applied by the Christian Religion towards the treatment of the environment particularly in terms of the disvirgining of the virgin forest that adds to the survival and existence of man. The study adopted expository, textual analysis and empirical method. The study revealed that Christian Religion with the adoption of the anthropocentric theory sees man as the center of value and that all the virgin forests which contain non-human creatures that contribute to man’s survival and existence, the ecosystem, the food chain and the interdependence of man with its environment and surrounding that leads to the improvement of the ozone layer and the improvement of climate change is destroyed and decimated by man due to the imbibing of the Christian Religion and the discarding of the African Traditional Religion by the Kolo Creek Clan people. Therefore, it concluded that there should be a balance between the Christian Religious doctrines as practiced in Africa.
| 5 |
Author(s):
Ifeanyi Peter Ezealaji, Benard Ifeanyi Odoh.
Page No : 41-44
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Silicon and Beyond: Unveiling the Hidden Elements Powering Modern Technology.
Abstract
In today's rapidly evolving technological landscape, silicon may dominate the conversation, but the true story of modern technology is far more complex. Behind every smartphone, electric vehicle, and renewable energy system lies a network of critical elements—lithium, cobalt, rare earth elements, and more—that are just as essential as silicon in driving innovation. These materials form the backbone of modern devices, but their extraction, availability, and environmental impacts present significant challenges. This article delves into the critical roles these elements play, examining their unique properties, applications, and the geopolitical and ethical considerations surrounding their acquisition. Through a detailed exploration of current research and case studies, we uncover the often-overlooked building blocks of the digital age and highlight pathways toward sustainable sourcing and recycling.
| 6 |
Author(s):
Ifeanyi Peter Ezealaji, Benard Ifeanyi Odoh, Chukwuneke J. J..
Page No : 45-51
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Integrating Geophysical and Hydrological Data for Improved Groundwater Exploration and Monitoring.
Abstract
Groundwater is a critical resource for many regions, particularly in Africa where it serves as a primary source of drinking water and irrigation. Effective groundwater exploration and monitoring require accurate data on subsurface conditions. This article explores the integration of geophysical and hydrological data to enhance groundwater exploration and monitoring. By combining methods such as electrical resistivity tomography (ERT), ground-penetrating radar (GPR), and time-domain electromagnetic (TDEM) surveys with hydrological data, more precise models of groundwater systems can be developed. The paper reviews recent advancements in geophysical techniques and their application in various case studies, including Kenya’s use of ERT for mapping aquifer systems and South Africa’s integration of GPR and hydrological data for managing groundwater resources. The integration approach provides a comprehensive understanding of subsurface conditions, improves groundwater resource management, and enhances predictive capabilities. This article also discusses the challenges associated with data integration and provides recommendations for future research and practice. By presenting a synthesis of current methodologies and practical examples, the study offers valuable insights for researchers, practitioners, and policymakers involved in groundwater management.
| 7 |
Author(s):
Akpoduado Christiana Ovie, Boyitie Paul Odiyirin.
Page No : 52-64
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Perceived Impact of Climate Change on Economic Activities in Ughelli North Local Government Area of Delta State.
Abstract
The study assessed household perception of climate change on economic activities in Ughelli north local government area of Delta State. Systematic sampling technique was employed to administer 291 copies of structured questionnaire to households in the area. Data obtained from the administered questionnaire were analyzed using simple percentages, tables, and principal components analysis (PCA). Results obtained showed households in the area were knowledgeable of climate change. The study revealed that households perceived the impacts of climate change to include increased temperature (55%), decreased rainfall (22.7%), and decreased in rainfall duration (12.4%). The study further identified households’ perceived changes in economic activities to include decreasing working hours engaged in economic activities, decreased in food crop farming/fish farming, drastic changes in principal sources of income and livelihood, changes in crop yields and productivity and changes in availability of fodder and non-timber forest product (NTFPs) as well as decrease in workforce productivity. PCA result identified the use of herbicide/insecticide/, burning of fossil fuel and deforestation, gas flaring and bush burning as main anthropogenic factors responsible for 80.2% of climate change phenomena in the area. Based on the findings, the study recommended that government should encourage soft loans to farmers and fish farmers. This will ensure the steady supply of food thereby increasing households’ source of livelihood and nutrition.
| 8 |
Author(s):
Adeboyejo Adeola Aarinola, Olusola Johnson Adeyinka.
Page No : 65-83
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Soil Seed Banks Dynamics and Restoration Potential of Some Selected Forest Reserves in Southwest, Nigeria.
Abstract
This research investigated the regeneration potential of soil seed-bank along three soil depths in three secondary forest communities within Southwest Nigeria, for a better understanding of the potentials of the soil seed banks in facilitating succession towards a more natural forest of native tree species in International Institute of Tropical Agriculture (IITA) Forest Ibadan, Elephant Forest reserve Omo and Emerald Forest in Ikoyi Nigeria. Eight temporary plots of 20m by 40m using systematic line transect were laid in each forest. Soil samples were taken at three depths of 0–5cm, 5–10cm and 10–15cm and the seed banks composition was determined under a greenhouse condition. The results show that IITA forest has an abundance of 93 species with the highest in soil depth of 5-10 (35) and least exist at 10-15cm (24). The species evenness ranged from 0.92 to 0.96, with an average value of 0.94. Emerald forest had a total of 74 tree species with 0-5cm depth having the highest specie abundance (34), while depth of 5-10cm (21) exhibit the least species abundance. At the forest, result of Species diversity indices show that at 0-5cm depth 2.47 index value was recorded, a value much higher than what was recorded at 5-10cm (2.40) and 10-15cm (2.36) respectively. The result of Elephant Forest reserve shows that a total of 87 tree species were recorded with 0-5cm depth having the highest specie abundance (40) followed by 5-10cm (27), 10-15 (26) respectively. The Shannon wiener index for Elephant Forest shows that 2.28 were recorded at 0-5cm depth, 1.40 at 5-10cm depth, and 1.70 at 10-15cm depth respectively. The soil seed bank could help in determining the status of regeneration potential of the three forests investigated. However, high dominance of tree species in the soil seed banks implies that the forest is disturbed and there is likelihood of tree species succeeding and dominating the forest ecosystem.
| 9 |
Author(s):
Taofeek A. Suleman, Isidore C. Ezema, Peter A. Aderonmu.
Page No : 84-101
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Critical Perspectives on the Adoption of Circular Design Strategies in the Built Environment for Sustainable Development in Sub-Saharan Africa.
Abstract
Adopting circular design strategies (CDS) in building development presents a transformative approach toward sustainability by promoting resource efficiency and reducing environmental impacts. This paper examined the current landscape of CDS adoption, focusing on barriers, enablers, benefits, and critical success factors within the built environment (BE) in Sub-Saharan Africa. Drawing on a comprehensive review of global contexts literature, the study identifies and categorizes 185 factors, subsequently pruning them to 121 pertinent to the design stage. Barriers such as low awareness, regulatory gaps, and economic constraints are explored alongside enablers like leadership commitment, technological innovation, and supportive policies. The paper underscores the pivotal role of these factors in shaping sustainable building practices, emphasizing the need for tailored strategies to overcome local socio-cultural, economic, and technological challenges in the BE of Sub-Saharan Africa. This research contributes a nuanced understanding of how CDS can be effectively integrated into the BE, offering practical implications for policymakers, industry stakeholders, and researchers striving to embrace sustainable practices.
| 10 |
Author(s):
Saheed Oyekunle Oyetunji, Popoola Idris Bamigboye.
Page No : 102-118
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Geospatial Analysis of Climate Change Impacts on Vegetation Dynamics in Owerri West, Imo State.
Abstract
Climate change is a global phenomenon with profound effects on the environment, economies, and societies. It refers to significant changes in global temperatures and weather patterns over time. This study explores the impact of climate change on vegetation in Owerri West, Imo State, Nigeria, using geospatial techniques over a 20-year period (2003–2023). By analyzing satellite imagery and Normalized Difference Vegetation Index (NDVI) values alongside key climatic variables such as precipitation and land surface temperature (LST), the research seeks to quantify the extent of vegetation changes due to climate variability. The study uses Landsat 8 satellite data to evaluate spatiotemporal trends in vegetation health. NDVI values in 2003 ranged from a high of 0.45, indicating healthy and dense vegetation, to a low of -0.04, representing barren areas. By 2013, NDVI values had drastically declined, with a maximum of 0.12 and a minimum of -0.33, despite an increase in precipitation from 3300 mm (2003) to 3900 mm (2013). This decline suggests that other factors, such as extreme weather events or urbanization, contributed to vegetation stress. In 2023, NDVI values showed partial recovery, with a maximum of 0.28 and a minimum of 0.05, although precipitation levels dropped to a range of 600 mm to 540 mm. The broader temperature range in 2023, with a maximum of 32°C and a minimum of 17°C, likely reduced heat stress, allowing for vegetation recovery, though still below the 2003 levels, The findings highlight the complex interplay between climatic variables and vegetation health, where precipitation and temperature changes significantly influence vegetation dynamics. However, the NDVI decline in 2013, despite high precipitation, suggests that anthropogenic factors like urbanization and land use changes also play a critical role. This research emphasizes the importance of integrating remote sensing and GIS for monitoring vegetation responses to climate change. The study calls for sustainable land management practices and climate adaptation strategies to enhance vegetation resilience in the region.
| 11 |
Author(s):
Dantani A..
Page No : 119-138
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Determination of Forest Health using Remote Sensing Techniques in Gashaka-Gumti National Park, Northeast, Nigeria.
Abstract
This study was conducted in order to determine the health status of forest vegetation in Gashaka-Gumti National Park with the view of providing information for biodiversity conservation and management decisions. Landsat images were downloaded from USGS website. The images were pre-processed using radiometric correction since the reflectance value were needed for computing spectral indices, the digital number were converted to radiance and reflectance, analysis was carried out using raster calculator was used. The range of NDVI, GNDVI, ARVI and MSI were used for health assessment. Over decades (2003–2023), utilizing NDVI, GNDVI, ARVI, and MSI as assessment tools revealed moderate to good health in most forest regions, with higher ARVI, GNDVI, and NDVI indicating healthier vegetation and elevated MSI values suggesting areas under moisture stress. the average values of NDVI, GNDVI, ARVI, and MSI over three decades indicate a potential decline in overall vegetation health, reduced green vegetation, changes in vegetation conditions, and a decrease in moisture stress, suggesting a potential increase in greening and photosynthetic activities in plants. These trends highlight the dynamic nature of the forest ecosystem over the studied period. Positive correlations between ARVI, GNDVI, and NDVI across years indicate a consistent vegetation pattern, while negative correlations with MSI suggest potential inverse relationships, providing valuable insights into forest health dynamics. Higher values of ARVI, GNDVI, and NDVI generally signify healthier vegetation, whereas elevated MSI values may indicate areas experiencing moisture stress, emphasizing the importance of monitoring these indices for sustainable forest management. The study recommends the sustained use of NDVI, GNDVI, ARVI, and MSI for forest health monitoring in the study area, implement integrated pest management based on identified stress conditions, utilize spatial maps for strategic timber harvest planning, develop climate-resilient management considering moisture stress, and invest in research for enhanced assessment precision and understanding of ecosystem dynamics.
| 12 |
Author(s):
Ololade Moses Olatunji, Henry Diepiriye Precious, Samuel Akpan Nta.
Page No : 139-145
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Assessment of the Effect of Vehicular Emission on Air Quality in Uyo.
Abstract
The presence of vehicular traffic in urban city centers due to urban expansion occasioned by rapid population growth has been of immense concern for many years; as emissions from vehicle exhausts poses a major threat to both public health and environmental quality. This trend is expected to continue as ownership of vehicles keeps increasings. In this study, attempts are made to measure the concentration of traffic related emissions, with a view to assess the intricate relationships between vehicular emissions, their effect on surrounding air quality, and their impact on public health by extension, in Uyo metropolis, using USEPA air quality index. Six sampling locations were selected for this analysis. In selecting the study locations, special preference was given to accessibility, availability of open space free from shed, meteorological consideration of upward and downward directions, areas with minimal local influence from vehicular movement. Also, consideration was given to the sensitivity and stability of the equipment, as well as its capability to reproduce results.
The concentrations of the priority pollutants (i.e, CO, H2S, SO2 and O) were measured with highly sensitive digital portable meters (Crowcon Gasman Monitors) in each of the selected locations, at peak traffic periods, and compared with standard air quality ratings. The results of the study showed that locations IRJ, IPJ and NRJ recorded relatively the highest measured concentrations of the pollutants (CO, H2S and SO2) respectively. While IPJ, NRJ and IRJ recorded the lowest measured concentrations of same pollutants respectively. Continuous accumulation of these toxic gases in air in air poses greater threat or may add to an already existing health burden of the residents of those locations. Therefore, further and thorough investigation is highly recommended to study the health impact of these contaminants in the residents.
| 13 |
Author(s):
Karikpo L. P., Ekweozor I. K. E., Daka E. R., Boisa N..
Page No : 146-166
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The Bioaccumulation and Risk Assessment of Total Petroleum Hydrocarbons in Aquatic Resources from K- Dere Shoreline, Rivers State, Nigeria.
Abstract
This research was designed to study the levels of Total Petroleum Hydrocarbon (TPH) in aquatic resources (Crab (Goniopsis cruentata), surface water and sediment) from K-Dere shoreline. Samples of sediment were collected inter-tidally. All samples were collected from six sampling stations, bi-monthly for a period of one year. Collected samples were transported to laboratory for chemical analysis. Gas Chromatography was used to analyse total petroleum hydrocarbon concentration in samples and data obtained were statistically analysed at p>0.05 using SPSS version 23. The mean concentration results obtained in surface water, sediment and biota across the stations were as follows; (590.75, 623.50, 451.17, 544.42, 674.67, 536.50mg/l) (8152.17, 6146.92, 44200.00, 4860.33, 2069.67and 5089.25mg/kg) and (131.5, 80.17,144.08, 109.08, 82.50, respectively. The mean concentration of TPH in sediment at station 1, 2 and 5 were above the intervention and permissible limit by former DPR (2022). The ecological risk assessment was expressed in terms Bio-sediment Accumulation Factor (BSAF) and Pollution Index (PI) was calculated for the aquatic resources. PI showed that most chemical compounds of TPH were higher than 1, indicating high pollution from anthropogenic sources. The health risk assessment was expressed in terms of Estimated Daily Intake (EDI) and Health Risk Index (HRI) indicated significant health risk, posing threat to human health of the locals. Further and histopathological studied should be carried out to determine the impact of TPH on biota. Shoreline Clean up should be implemented with post clean-up assessment.
| 14 |
Author(s):
Ayub Hassan Ulusow, Zamzam Osman Abdi.
Page No : 167-178
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The Role of Psychological Resilience in Somali Communities Facing Climate Change.
Abstract
Abstract: Climate change presents a significant concern to Somalia, especially impacting its susceptible pastoralist and agricultural communities. The nation faces significant droughts, floods, and land degradation, with socio-economic repercussions intensified by persistent conflict, poverty, and displacement. In this situation, psychological resilience is essential for individuals and communities to adapt to environmental difficulties. This study investigates the function of psychological resilience among Somali communities confronting climate change, analysing the mechanisms via which resilience is cultivated and maintained via social, cultural, and religious structures. The research used a mixed-methods approach, utilising qualitative interviews and quantitative surveys done throughout Somalia's many regions, concentrating on both pastoralist and agricultural communities.
The findings reveal that social support networks, religious faith, and community solidarity are key components of psychological resilience, providing emotional and material support during times of crisis. Notably, pastoralist communities exhibited higher resilience levels than farming communities, highlighting the adaptive nature of nomadic livelihoods. Gender dynamics also emerged, with women in rural areas facing unique challenges, though participation in community and religious organizations bolstered their resilience. This study underscores the importance of incorporating mental health and social cohesion into climate adaptation strategies, advocating for community-based interventions that enhance psychological resilience. By fostering these resilience mechanisms, Somali communities can better navigate the long-term impacts of climate change, contributing to their overall well-being and sustainability.
| 15 |
Author(s):
Oyun Mathew Banji, Sobola Oluronke Olubunmi, Fasinmirin J. T., Mafimisebi T. E., Adeyemo J. A., Wole-Alo F. I., Jayeoba O. J..
Page No : 179-192
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Soil Fertility Management Practices of Smallholder Farming Communities in Nasarawa State, Nigeria.
Abstract
This study assesses soil fertility management practices among smallholder farming communities in five Local Government Areas (LGAs) of Nasarawa State, Nigeria. A total of 150 respondents were selected using multistage sampling technique. Data were collected using semi-structured questionnaires, capturing information on socioeconomic characteristics, soil fertility practices, and challenges. The results showed that 93.33% of respondents in Lafia LGA and 96.67% in Obi LGA practiced soil conservation methods, with the most common techniques being cover cropping, used by 86.67% of farmers in Obi, and organic manure application, adopted by 100% of respondents in Akwanga, Doma, and Nasarawa Eggon LGAs. Chemical fertilizer usage was relatively lower, ranging from 6.67% in Obi to 50% in Lafia. Major challenges faced by farmers included inadequate knowledge of soil management, identified by 100% of respondents in Akwanga, and high fertilizer costs, reported by 70% of respondents in Lafia and Obi LGAs. Education played a significant role in adopting soil fertility practices, as respondents with tertiary education were more likely to employ modern techniques like conservation tillage and agroforestry. Despite these practices, limited access to organic materials and technical knowledge hindered broader adoption of Integrated Nutrient Management (INM). The study highlights the need for tailored interventions, such as farmer education and capacity building, to improve soil health and agricultural productivity. These findings provide a foundation for developing policies that promote sustainable farming practices, ensuring long-term food security in Nasarawa State and Nigeria as a whole.
| 16 |
Author(s):
Bridget Omon Adediran, Ifeoluwa Oluwatosin Olayemi, Maria Modupe Adeyemi.
Page No : 193-210
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The Role of Phenol and Flavonoid in the Synthesis and Application of Nano Graphene Oxide.
Abstract
The unique properties of graphene oxide have generated significant interest in recent years. Many potent aromatic drugs are water-insoluble, complicating their administration. Nano graphene oxide, a potential drug carrier, is typically synthesized through environmentally harmful chemical methods. This review emphasizes the need for more sustainable approaches to address these challenges while maintaining graphene oxide's effectiveness in drug delivery.
Plant extracts are rich in bioactive compounds known as phytochemicals which have the ability to synthesize nano graphene oxide. A large and most intricate class of these phytochemicals are Phenolic compounds which have an aromatic ring and one or more hydroxyl groups in their structural conformations. Based on their structural composition, they are divided into subgroups that include phenolic acids, flavonoids, tannins, coumarins, lignans, quinones, stilbenes, and carotenoids. Plant polyphenols are gaining increasing attention because of their potent antioxidant properties and important roles in preventing oxidative stress-related diseases. The extraction, identification, and characterization of phenolic compounds from a range of plant sources has become a major area of study in the health and medical fields in recent years. The role of phenol and flavonoid in the synthesis and application of nano composites are also covered in this review.
| 17 |
Author(s):
Enobong Ebenezzar Uffort, Lucky Odokuma, Caroline Ariole.
Page No : 211-220
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Response of Marine Microalgae and Copepod to Toxicity of an Effluent.
Abstract
Discharges of treated effluents from producing industries is a continuous source of pollutants to the marine ecosystems. Typically, effluents comprise of one or more pollutants such as hydrocarbons, heavy metal rinses and detergents of which after treatment, the pollutants may be at a level that could affect the marine ecosystem. This study aimed to determine the acute toxicity of the treated effluent and the response of Microalgae-Skeletonema costatum and Copepod-Acartia tonsa when exposed to the treated effluent in a marine system.
The microalgae and copepod which are standard test organisms for acute toxicity testing as selected by Nigerian Upstream Petroleum Regulatory Commission were sourced from Nigerian Institute for Oceanography and Marine Research, Buguma in Rivers State, acclimatized to laboratory conditions and utilized in whole effluent acute toxicity test of the effluent. Utilizing different concentrations of the treated effluent, growth inhibition test (for microalgae) and mortality test (for copepod) was performed using static without renewal option at 22oC under continuous white light for 72hours. Thereafter, median inhibition/lethal concentration (IC50/LC50) were calculated. The treated effluent was more toxic to Acartia tonsa (72hours-LC50 473.19mg/l) when compared to Skeletonema costatum which had 72hours-IC50 >100,000mg/l. The study revealed that the treated effluent displayed moderate toxicity to the copepod and was non-toxic to the microalgae. Hence, more efforts should be put in place by the regulatory agencies in ensuring that operators adhere strictly to effective guidelines of waste water treatment to avoid extinction of sensitive species.
| 18 |
Author(s):
Enobong Ebenezzar Uffort, Lucky Odokuma.
Page No : 221-231
|
Response of Tilapia Guineensis and Clibanarius Africanus to Acute Toxicity of Two Oil Spill Dispersants.
Abstract
Activities associated with crude oil, natural gas or condensate field could result in several accidents that can lead to massive oil spills. To curb the deleterious effect of the hydrocarbon contents of the crude oil, the chemical clean-up method can be utilized in far and deep offshore environments in Nigeria. Using the dispersants weakens the interfacial tension between oil and water and in the process, bitty droplets of the oil are hatched and entrained within water column. Acute toxicity testing becomes vital as the dispersants have the potentials of causing deleterious effects on resident organisms within the recipient environment. This study aimed to determine the acute toxicity of two oil spill dispersants and the response of the euryhaline-Tilapia guineensis (fish) and benthic-Clibanarius africanus (hermit crab) when exposed to the dispersants. The fish and hermit crab which are standard test organisms for acute toxicity testing in Nigeria as specified by Nigerian Upstream Petroleum Regulatory Commission (NUPRC) were sourced from Nigerian Institute for Oceanography and Marine Research (NIOMR) at Buguma, Rivers State while the dispersants- Corexit 9527 and Finasol OSR were obtained from different licensed oil field chemical stores in Port Harcourt, Rivers State, Nigeria. For the test organisms to adjust to new environment, they were first acclimatized before conducting the range finding test. Based on the results obtained from the range finding test, the definitive test concentration was established at 0.2, 0.4, 0.6, 0.8, 1.0ppt and 2, 4, 6, 8,10ppt for Tilapia guineensis and Clibanarius africanus respectively. Reference experimental group was also instituted using Potassium Chloride at concentrations of 20, 40, 60, 80 and 100ppt. The median lethal concentration (LC50) was calculated from the mortality value using Probit software. Mortality rates increased with increase in concentration of the toxicants and exposure time. The 96hours-LC50 values for Corexit 9527 were 4669mg/l and 181mg/l for Clibanarius africanus and Tilapia guineensis respectively while that of Finasol OSR were 4268mg/l and 188mg/l for Clibanarius africanus and Tilapia guineensis respectively. The study revealed that Tilapia guineensis was more sensitive as the two dispersants were less toxic to hermit crab and more toxic to the fish. Hence, adequate enforcement of regulations on the use of these chemicals should be adhered to in the water column of marine environments and more attention be inclined to biologically derived chemicals (biosurfactants).
Keywords: Acute toxicity, Dispersants, Tilapia guineensis, Clibanarius africanus
