SW Nigeria Research Articles

CANOPY ARCHITECTURE AND GRAIN YIELD OF MAIZE (ZEA MAYS L.) IN THE RAINFOREST OF SOUTHWESTERN NIGERIA

Plant architecture is a key factor for optimum productivity in most crops. Unfortunately, this aspect of maize (Zea mays L.) crop configuration has recieved little attention from researchers in the rainforest ecologies of Nigeria.We investigated the effects of the environment on canopy architecture and, in turn, canopy orientation on grain yield of maize in the rainforest of sw Nigeria. Five maize varieties were planted weekly from March to November of 2016 and 2017 in randomized complete block experiments at the Obafemi Awolowo University Teaching & Research Farm (OAU T&RF). Data were collected on canopy architecture, which was quantified with upper and lower leaf angle (LAUpper and LALower) and leaf orientation values (LOVUpper and LOVLower) obtained at the grain-filling stage.-At maturity, grain yield, along with some of its components (ear length, ear diameter and kernel row number) were also obtained from all plots. The data were subjectedto ANOVA, correlation, regression, and sequential path analyses to determine the relationship of grain yield with canopy architecture. The environment and genotype had significant effects on canopy architecture, grain yield (P = 0.01; R2 ≥ 80 %), and yield components. Leaf orientation value of the upper canopy (LOVUpper), with correlation coefficient r = 0.61** and direct positive causal effect (P = 0.61), rather than LAUpper, LALower and LOVLower, greatly affected grain yield. In conclusion, LOVUpper was the single most important leaf architecture index that positively affected grain yield which, in turn, was influenced greatly by the environment in the rainforest ecology of SW Nigeria

Spatio-Temporal Assessment of Surface Water Quality in an Agrarian Community, SW Nigeria Using Globe Protocol

Abstract. This study was undertaken to assess some physical parameters (pH, dissolved oxygen, total dissolved solids, salinity, conductivity and oxidation-reduction potential) of stream water within the Ilara–Mokin community Ondo State, Nigeria, using standard GLOBE protocol. The data were subjected to descriptive statistics and crossplot analyses to explore the relationships among the parameters and compare the measured parameters to Nigerian and international standards. Based on these parameters, we determined the portability of stream water, evaluated and discussed the impact of these parameters on the quality of surface water of Ilara–Mokin. Parameter values were higher in the dry season compared to the wet season. Parameter concentrations correlate well with population density. Parameters' values were predominantly higher or lower than national and international standards both in dry and wet seasons. A positive association exists between TDS-salinity, TDS-EC and EC-salinity in the dry season. TDS and salinity's correlation suggests that the dissolve solids emanate from municipal wastes. The Salinity-EC relationship was strong and only held in the dry season due to high insolation and the consequent very high evaporation rate and reduced water discharge, which in turn led to increased concentration of dissolved salts in the stream water. Only TDS and Salinity exhibited positively associated in the wet season. Regardless of the season, we observed that TDS, Salinity and EC values are defiant with Nigeria and WHO standards; hence, the water is unsuitable for human consumption. Nevertheless, the studied watershed's surface water resources can meet the domestic water demand of the Ilara-Mokin community if remediated.

Sn-Ta-Nb mineralization potential of pegmatitic bodies in Bunu area, part of Kabba-Lokoja-Igarra Schist Belt, SW Nigeria

The Bunu area in Southwestern Nigeria lies within the Basement Complex that forms part of the Pan-African platform of the crystalline rocks. The complex lies within the vast Trans-Saharan Pan African mobile of Neoproterozoic. The belt is characterized by voluminous post-collision granitoid plutons that are well exposed around the study area. The Bunu area consist of two major lithologic suites namely: (i) the gneiss-schist suite which comprised of Migmatized-gniess/ Migmatized Schist and quartz/mica schist with interbedded amphibolites (ii) intrusive suite that include fine-medium grained granite, medium-coarsed grained granodiorite and porphyritic granite and the minor intrusions like pegmatite, aplite, dolerite and quartz veins. Pegmatite outcrops in the Bunu area of the Kabba-Lokoja-Igarra Schist belt belong to the rare-element type and are mined for columbite-tantalite and gem tourmaline. Pegmatitic textures are well developed, these include large K-feldspar (comb textures), layering and graphic intergrowth of K-feldspar + albite + quartz + schorl and linearly arranged garnet crystals that may be developed at deeper levels of the dyke. Ductile and brittle structural features mapped in the area from remotely sensed and field data are generally consistent with the N-S and NE-SW regional orientation associated with Pan-African event and with minor axes of NNW-SSE and E-W planar structures. Trace elements geochemistry of the pegmatite (bulk rock and mineral extracts of K-feldspars and Mica) revealed that Rb, Sr, Ba, Li and Cs are enhanced in the Otafun and Okutose pegmatites indicating higher fractionation levels. Also, the rare-metals Nb, Ta and Sn were also enriched in the most evolved Otafun and Okutose pegmatites. Trace-element variations in mica from the pegmatites indicate that they are per-aluminous LCT (lithium, cesium, and tantalum) family and bery-columbite subtype. The origin of the gradual composition variation trend observed from the host granite bodies to the pegmatites reflects the increasingly fractionated melt composition and systematic enrichment of the incompatible trace elements Li, Rb, Cs, Be, Na, Ta and Sn. The Zr-SiO2 and Sr-Rb plots of the pegmatite bulk rock samples suggest that they are genetically magmatic and poorly differentiated with little or no post-magmatic metasomatism. Ta vs Cs and Ta vs Ga plots for the chemistry of K-feldspar and muscovite mineral extracts from the pegmatites in Bunu area show potential for tantalum and niobium (>75 ppm) mineralization, thus implying that the mineralization in these pegmatites is probable, therefore investors should use caution.

Luminescence dating of holocene siliciclastic sediments in eastern Dahomey Basin, southwestern Nigeria

Several attempts at reconstructing geological settings and palaeoclimatic changes of the siliciclastic deposits of the Dahomey Basin, SW Nigeria, using relative age dating and correlation methods, have resulted in serious discrepancies on the ages. Therefore, a chronology framework established by an absolute age dating method is requisite to constrain the geological interpretation. This research focuses on quartz optically stimulated luminescence (OSL) dating of the upper siliciclastic sediments to help bridge the lacuna that arose from previous relative geologic dating. Ten sub-surface sediment samples were collected from the eastern part of the basin, and quartz OSL dating using single-aliquot regenerative-dose protocol was conducted for all the samples. The OSL signals appear well bleached prior to deposition and the OSL ages are reliable and robust. Through the application of OSL, the age framework of the uppermost part of sediments in the study area was established. The OSL dating results revealed that these depositional periods fall within the Holocene and are concentrated during two groups: 3.52 ka–1.55 ka, and 0.64 ka–0.05 ka. The samples with ages of 3.52 ka–1.55 ka distribute in the belt-like inland zone approximately parallel to the coastline. This deposition episode appears to be caused by the decrease in relative sea level during late Holocene. Thus, this study sheds light on the understanding past coast dynamics in the region.

An Integrative Laser Diffraction and Sieving Approach to Characterise Clastic Sediments of River Ero, SW Nigeria

An Integrative Laser Diffraction and Sieving Approach to Characterise Clastic Sediments of River Ero, SW Nigeria

Planting date effects on maize (Zea mays L.) growth and development in the rainforest of southwestern Nigeria

This study was conducted to determine the optimum planting date for maize (Zea mays L.) to cope with the negative impacts of climate change in the marginal rainforest agro-ecology as typified at Ile-Ife, SW Nigeria. Five maize varieties were planted weekly, in 3-replicate randomized complete block design experiments at the Obafemi Awolowo University Teaching and Research Farm, throughout the 2016 and 2017 cropping seasons. The varieties were monitored for seedling and adult plant traits including grain yield with its components. Statistical analysis showed significant effect of planting dates (DOP) on all traits. The first few DOPs in March and April had the highest grain yield which reduced with delayed planting till June and increased again mid July/August before finally dropping off thereafter. The higher yield in the earlier dates each year, was due to early flowering and taller plants with higher ear placement. Planting after the first few rains in March/April was the optimum for the first cropping season, and late July to mid-August was best for the second cropping season in this agroclimatic zone. Planting beyond these periods results in poor grain yield and pre-disposes the crop to terminal drought, which could result in complete crop failure.

Temperature and Short- wave Irradiation Trends in Ikogosi Climatic Change Pattern

Every living or non-living thing has its unique temperature consequent of absorption of electromagnetic radiation, light. The source of this molecular kinetic is Solar energy incident on Earth’s surface, the sole supplier of life on the planet. This phenomenon markedly determines the climatic conditions in our habitat. Atypical of previous much-required characteristic balance in nature, myriads of surface processes, ranging from evaporation, photosynthesis and even terrestrial carbon uptake effects are becoming altered in nature. These effects on long-term timing of events defines global warming, it distinguishes the diurnal from seasonal course of surface temperatures and shortwave radiation which contains larger quantity of energy and longwave radiation which holds less amount of energy. Earth’s emitted longwave radiation, also has major practical implications on solar energy technologies, agricultural productivity, profound environmental, societal, and economic implications. There is cumulative evidence that the volume of solar radiation incident on the Earth’s surface is not constant but experiences substantial decadal variations. In view of the certainty of unpredictability of these climatic changes, a positive recourse lies in utilizing these enormous natural forces to solve Man’s energy crisis challenge. Thus, this study uses meteorological data from MERRE to investigate the prospect of shortwave radiation in Ikogosi SW Nigeria and its implications technologically and environmentally in the future of energy prospecting first locally, and on a spatial scale.

Geoelectrical resistivity imaging of shallow oil sands in the Eastern Dahomey Basin (SW Nigeria): Implication for heavy oil exploration and production

The Eastern Dahomey Basin hosts an extensive reserve of oil sands, a significant portion of which is unexplored and located within the southwestern part of Nigeria. Here, we use detailed outcrop mapping and Electrical Resistivity Tomography (ERT) to investigate the physical and geological characteristics of the oil sands and surrounding lithological units within the Eastern Dahomey Basin in SW Nigeria. The oil sands in the studied outcrop belong to the Turonian to Maastrichtian sandstones of the Afowo Formation which is characterized by active bitumen seepage along the length of the outcrop. The ERT results reveal lateral and vertical variability of the overburden and oil sands units in the study area. The oil sands are characterised by two unique geoelectric anomalies. Each of these anomalies has higher resistivity values (>3713 Ωm) compared to the low resistivity values of the topsoil/laterite overburden (160–2790 Ωm) and the underlying clay dominated interval (160–1576 Ωm). Importantly, the oil sands have variable thicknesses of up to 20 m and are located at shallow depths (~1–5 m below ground level). Hence, the oil sands can be exploited using surface mining techniques. This study provides a detailed assessment into the application of a non-invasive geophysical techniques for characterising oil sands near an active seep system, with implications for drawing up exploitation strategies.

Evaluation of Saline Water Intrusion and Suitability of Groundwater for Domestic Purposes in Lagos Coastal Area, SW Nigeria: Using NIOMR Jetty as a Case Study

Evaluation of Saline Water Intrusion and Suitability of Groundwater for Domestic Purposes in Lagos Coastal Area, SW Nigeria: Using NIOMR Jetty as a Case Study

Evaluation of the groundwater potential of Modomo Community in Ile-Ife, Southwest Nigeria, using integrated geophysical techniques

Integrated geophysical investigation involving 1D vertical electrical sounding and 2D electrical resistivity tomography was carried out in the Precambrian Basement Complex terrain of Modomo, SW Nigeria, with challenges of groundwater development. The objective was to use the geoelectric parameters to characterize the study area into groundwater potential zones that would assist the siting of productive wells/boreholes. Thin (generally 5 m, while success and failure rates of 83–100% and 57% were observed for wells/boreholes sited within partly weathered/fractured basement and fresh basement, respectively. The generated groundwater potential map rated the study area as very low (11.6%), low (51.8%), moderate (30%) and high (6.6%). Areas with moderate and high potential ratings accounted for 73% and 50% of well/borehole development success rates, respectively, while 60% and 44% failure rates characterized the very low and low groundwater potential zones. The groundwater potential map is significantly validated by the existing well/borehole yield information. This demonstrates the reliability of this technique of groundwater potential assessment in the basement complex environment with groundwater development challenges.

Evaluating the groundwater potential of coastal aquifer using geoelectrical resistivity survey and porosity estimation: A case in Ota, SW Nigeria

Geoelectrical resistivity sounding surveys was carried out at two locations (A and B) in the new CanaanCity residential estate of Canaan land Ota, Ogun state in order to locate possible targets for groundwater explorations. A total of twelve (12) vertical electrical soundings were conducted using the Schlumberger array configuration. The interpretations of the VES curves revealed five to six geoelectrical layers at location A which comprises VES1-7. The geoelectric units consist of the topsoil, sandy clay, lateritic clay, confining bed (clayey sand), and main aquifer (sand). The top of the aquifer in this part of the study area is between 40 m and 83.5 m. Likewise, a total of five to seven layers of geoelectrical units were delineated at the location B portion of the study site (VES 8–12) similar to location A with an addition of the shale unit that was interpreted to be that of the Akimbo Formation of the Dahomey Basin. The depth to the top of the productive aquifer within location B is in the range of 40–112.4 m. The delineated basal shale layer is impermeable, serving as the base seal rock for the confined aquifer system. The estimated porosity values range from 28% to 74%, indicating that the highly porous aquifer system in the area is the coastal plain sands mixed with the alluvium sand of the Benin Formation of Dahomey Basin. The study revealed the complexity of the productive aquifer system in the area and its undulating topography.

Source rock maturity and petroleum generation in the Dahomey Basin SW Nigeria: Insights from geologic and geochemical modelling

Sedimentology, foraminifera paleoecology, geochemical and petroleum system modelling studies were performed on Cretaceous shales from onshore Orimedu-1 and offshore X (at a water depth of 914 m) wells in the Dahomey Basin, southwestern Nigeria to evaluate their maturity, hydrocarbon generation potentials, and regional significance for petroleum prospectivity. Foraminifera biofacies analysis of the studied shales suggests deposition in dominantly marine environments. The average total organic carbon content (TOC, wt%) and hydrogen index (HI, mgHC/gTOC) for Cenomanian, Turonian, and Coniacian shales in X-well are 1.3, 0.9, 1.3 and 406, 560, 214 respectively. While the Cenomanian and Turonian shales in Orimedu-1 have TOC (wt%) of 1.3 and 1.9, and HI (mgHC/gTOC) of 179 and 357 respectively. Well X source rocks contain predominantly marine-derived Type II kerogen, while Orimedu-1 well contain terrigenous-derived gas prone kerogen. The integration of recently acquired kinetic data from immature source rocks further constraints the prediction of petroleum generation in the study area.1D basin modelling of X well reveals that the Cenomanian Source Rock (CSR) is the most mature bed in the basin having attained the initial 10% transformation ratio (TR) at 87 Ma, got to peak TR (~50%) at 86 Ma, and reached 83% at 53.6 Ma With a present-day thermal maturity of 0.95% VRo. The Turonian source in well X also attained the initial 10% TR at 87 Ma, got to peak (~50% TR) at 86 Ma and 69% TR at 50 Ma. These modelled source beds are deeper than the source with 0.62 %VRo used for kinetic study. The observed maturity trend is mostly controlled by the regional erosive events associated with the West African rift system during Santonian and Eocene times. The source rocks in Orimedu-1 are immature. The timing of the generated and expelled hydrocarbons into the Cretaceous petroleum systems of Dahomey Basin is of regional significance with the entire Gulf of Guinea basins because of the similar evolution and sedimentation history along with recent discoveries and production of hydrocarbon.

Assessment of land use impact and seepage erosion contributions to seasonal variations in riverbank stability: The Iju River, SW Nigeria

The Iju (Atuwara) River is an important component of the Owo River catchment (ORC), which supports the livelihood of millions of people in Lagos and Ogun States of southwestern Nigeria. However, rapid urbanisation and numerous anthropogenic activities have caused significant changes in the natural flow regime of the river, resulting in serious bank erosion. In many riparian areas, accelerated bank erosion has been attributed to the combined effects of seepage erosion and fluvial undercutting of the bank toe due to the hydraulic stress of the river on the bank. This research, therefore, investigated the combined effects of seepage erosion, riparian vegetation (root cohesion), tension crack, and land use/land cover (LULC) change on the stability of riverbanks on the Iju River, Nigeria. Multi-temporal LULC datasets acquired from remotely sensed Landsat images of 1999, 2009, and 2019 were used to map LULC changes in the ORC. Laboratory tests were conducted to determine the geotechnical properties of the riverbanks followed by bank stability analysis and evaluation of the erosion potential of the riverbanks using the Bank Stability and Toe Erosion Model (BSTEM) and Bank Erosion Hazard Index (BEHI), respectively. The BSTEM results indicate that the factor of safety (Fs) decreased with an increase in seepage undercutting distance (du), irrespective of the bank angle. The correlation of Fs with root cohesion (cr) and depth of tension crack (zc) shows that Fs was positively correlated with cr but decreased with an increase in zc. LULC change results show that the natural flow regimes of rivers within the ORC have been adversely affected by the combined decrease in vegetation and wetlands, with a corresponding increase in the spatial extents of the built-up area and cultivated land/open spaces. These research findings are essential for the development of a watershed-scale natural disaster management framework for the southwest ecoregion of Nigeria.

Effects of biochar and poultry manure on soil properties, growth, quality, and yield of cocoyam (Xanthosoma sagittifolium Schott) in degraded tropical sandy soil

AbstractUse of biochar (B) and poultry manure (PM) as soil amendments can improve the productivity and sustainability of tropical agriculture. Our fieldwork is the first research on the agronomic use of B and PM for the growth of cocoyam in sandy soil of the humid tropics. In this study, the effects of B, PM and their mixture were investigated on soil properties, mineral and nutrient concentrations, growth, and corm and cormel yields of cocoyam during the 2017 and 2018 cropping seasons. The experiment consisted of 4 × 2 factorial combinations of B (0, 10, 20, and 30 Mg ha−1) and PM (0 and 7.5 Mg ha−1). In both years, the application of B and PM either alone or in combination improved soil physical and chemical properties, plant nutritional status, growth, and corm and cormel yields of cocoyam. The combination of 30 Mg ha−1 B and 7.5 Mg ha−1 PM (B30 + PM7.5) gave the highest corm and cormel yields of cocoyam. Pooled over the 2 years, application of B at 30 Mg ha−1 and PM at 7.5 Mg ha−1 (B30 + PM7.5) significantly increased corm yield of cocoyam by 47 and 66%, respectively, when compared with sole PM at 7.5 Mg ha−1 and B at 30 Mg ha−1. Lowest corm and cormel yields were obtained for the unmanure control. The combination of 30 Mg ha−1 B and 7.5 Mg ha−1 PM is recommended for soil fertility management and cocoyam production in the rainforest agroecology of SW Nigeria.

Magnetic rocks distribution and depth to basement analysis on an old Quarry Site, Abeokuta, SW Nigeria

Geomagnetic study was carried out to investigate the distribution and depth of formations of different magnetic rocks on an old quarry site, Abeokuta, Southwestern, Nigeria. Eight ground magnetic profiles were established with 10 m spacing intervals orientated in West-East and North-South directions, and ranged between 110 and 190 m. A total of 223 data sets were acquired and corrected for all forms of magnetic variations. The resulting residual anomalies were plotted against distance using Microsoft Excel tool. Also, these anomalies were modeled into 2D and 3D contour sections using Surfer 10. The depth to basement analysis was carried out using Peter’s half slope graphical method. The resulting profiles and contour sections revealed variable anomalies which indicated contrast in the magnetic distributions of the subsurface. Mineral rocks with average (0-150 nT) magnetic susceptibilities dominated the profiles, and this indicated that the study area is on pegmatite or Quartz vein which probably harbored Beryl, Graphite, Sandstone, Quartz, Tantalite and Mica in both massive and disseminated quantities. Regions with high (150-300 nT) and low (0 to -150 nT) magnetic susceptibilities were also observed across the profiles. Mineral rocks with very thin bodies were observed at depths 3.48-17.42 m, intermediate bodies were buried at depths 2.61-13.06 m, while very thick bodies were located at depths between 2.09 and 10.45 m. The depth of the magnetic sources revealed that the major and minor mineral rock contact in the study area.

Mycobacterium ulcerans Infection (Buruli Ulcer) in Southwest Nigeria

Objectives: Buruli Ulcer Disease (BUD) caused by Mycobacterium ulcerans is a severe neglected tropical disease of the skin, which has been reported in over 33 countries globally including Nigeria where the disease was first reported in 1967 and later in 1975. Since these reports, there has been no research on BU in the southwest Nigeria. In this study we assessed the presence of BUD in five states of the southwest Nigeria. Method: This was a community-based, cross-sectional study where BU awareness sessions preceded active search for suspected cases. Questionnaires were administered for participants' demography. Swab and fine needle aspirate specimens from suspected BU lesions were subjected to IS2404-based Nested PCR and Real time (qPCR) techniques to confirm BUD. Results: A total of 256 samples were collected and analyzed between April, 2016 and December, 2018. 157 (61.3%) samples were positive to IS2404 of M. ulcerans. Children below 15 years of age and adults constituted 42 cases (26.8%) and 115 cases (73.2%), respectively. Index BU cases were confirmed in Ekiti 4 (2.5%), Lagos 11 (7.3%), Ondo 16 (10.6%), Osun 61 (38.9%) and the remaining 64 (40.4%) were found in Ogun State. Ogun and Osun States accounted for 79.3% of all confirmed BU cases in this study. Conclusions: Conclusion: BU cases, for the first time, were confirmed in five states of SW Nigeria with two of them (Ogun and Osun States) indicating endemic situation, hence the need for those states to be kept under surveillance as potential BU flash points. On a larger scale, a robust BU awareness program nationwide should be embarked upon by the government and other stakeholders. J Microbiol Infect Dis 2020; 10(2):82-88.

English

An attempt was made to use remote sensing technique to analyze some structural components of the metamorphic basement complex of the Ikare area in the SW Nigeria. Multiple data sets coupled with application of directional filtering techniques were used to extract linear features from Landsat ETM+ image with a view to improving on already produced regional structural map of the area and also determine a fast and cost effective approach to lineament mapping when handling multiple datasets. Band 7 (2.080 - 2.35) µm of the ETM+ image was used as a single band to visually extract linear feature while Principal Component Analysis (PCA) technique was employed in generating a multi-band enhanced image used to extract linear features. Four standard directional filters, Sobel (NS, EW, NW_SE and NE_SW) were further applied to enhance visual interpretation. The result shows that the area was affected by both ductile and brittle deformations at a regional scale, at least two episodes of deformations. A first episode of deformation (D1) produced the NW - SE tight to isoclinal fold in style (F1) and a second episode of deformation (D2) which affected the axial trace of the first episode to produce a N - S gentle to open fold (F2). Furthermore, the result shows that spatial domain filtering significantly improves the amount of lineaments that can be mapped and single band analysis is a rather fast and cost effective method of lineament extraction. Key words: Lineament mapping, directional filters, Ikare, &nbsp

A Hydrogeophysical Appraisals for Surficial Aquifer Potentials of Sedimentary Basin of SW Nigeria

A Hydrogeophysical Appraisals for Surficial Aquifer Potentials of Sedimentary Basin of SW Nigeria

Radiogenic Components of Limestone Samples Collected from Ewekoro SW Nigeria: Implications for Public Radiological Health Risks Assessment and Monitoring.

AIM:This research presents the radiogenic components in thirteen limestone samples from a quarry site in Ewekoro, southwestern Nigeria.METHODS:The distributions of natural radionuclides (238U, 232Th and 40K) in the limestone samples were determined by gamma spectroscopy using a well-type thallium-doped sodium iodide detector. Also, estimated associated radiological hazards are presented and compared with the standard threshold values.RESULTS:The activity concentrations for 238U, 232Th and 40K radionuclides range 18.09 ± 3.43-239.50 ± 25.74 Bqkg-1, 8.33 ± 0.83 - 360.01 ± 21.33 Bqkg-1 and 11.28 ± 0.81-735.26 ± 0.95 Bqkg-1 respectively. The radium equivalent activity concentration in the samples ranges 58.857-758.832 Bqkg-1 with samples S3, S4 and S11 values higher than the threshold limit of 370 Bqkg-1. Estimated dose rate and annual effective dose rate (AEDE) from the samples have ranges 28.754-330.917 nGyh-1 and 35.26-405.84 μSvy−1 respectively greater than the standard limit of 59 nGyh-1 and 70 μSvy−1 respectively for all samples except S9. The estimated external and internal indices are ranging 0.16 – 2.05 and 0.21 – 2.68 respectively, greater than permissible unity in some limestone samples such as S3, S4, S8, S11 and S13. Excess lifetime cancer risk was also computed using a life expectancy of 54.5 years. The results of higher radiological parameters in the limestone samples revealed that the miners have a high probability of contracting induced cancer.CONCLUSION:A regular check-up is recommended for the miners and staffs within the quarry site. Also, the residents within the environs should be relocated far away from the quarry site, as the particulates from the limestone rock blasting could contaminate the air in the study area.

Geospatial distribution of heavy metal contamination in Ewekoro Limestone, SW Nigeria

Limestone exploration has numerous advantage to the nation’s economy. However, major anthropogenic activities such as mining of such mineral deposits causes environmental contamination due to heavy metals pollution. The presence of heavy metals such as lead, cadmium, mercury and arsenic can interfere with the biochemical pathways by interaction with enzymes and proteins. They equally have the capacity to alter the DNA repair mechanism and act as the inducers of carcinogenesis. The focus of the research is therefore to detect the extent of heavy metals contaminations within the sampled Ewekoro limestone, southwestern Nigeria and to ascertain the risks they posed to the quarry workers, miners and the people residing in the study area.