Moshood Tijani | University of Ibadan (original) (raw)

Papers by Moshood Tijani

African Journal of Science and Technology, 2010

Environmental Earth Sciences, 2021

The poor quality and inconsistent nature of most surface water supply in arid and semi-arid regio... more The poor quality and inconsistent nature of most surface water supply in arid and semi-arid regions of the world has increased the reliance on groundwater resources. However, the susceptibility of groundwater to anthropogenic pollution in most cities and rural communities in Nigeria has become a major source of concern. In this study, the protective capacity of the aquifers in parts of the Bauchi State, Northeastern, Nigeria, from surface contamination was investigated in light of the geoelectrical characteristics of the overburden materials for sustainable management of the resources. This study applied a geographical information system (GIS) technique to secondary geoelectrical parameters (Dar-Zarrouk) derived from 94 vertical electrical soundings (VES) to delineate aquifer vulnerability zones. Five different thematic maps (topsoil longitudinal unit conductance, total overburden longitudinal unit conductance, total transverse unit resistance, coefficient of anisotropy, and total overburden isopach) were developed. Suitable weights were assigned to the thematic maps based on their relative influence on the protection of groundwater systems in the area. Subsequently, the ranks of the subclasses of the themes were reclassified based on their respective suitability before the thematic maps were integrated using ArcGIS 10.3 software to generate the overall aquifer protective capacity map of the study area. To validate the map, water samples were collected from 40 wells and trace elements (e.g., Ni, Cu, Sb, Cr, and As) were analyzed. The study area was categorized into three aquifer vulnerability zones: moderate (32.4%), weak/fair (54.5%), and low/poor (13.1%). Moderate zones with limited portions of fair/weak zones were the predominant zones within the basement setting. This reflects the occurrence of clayey saprolitic units within the basement terrain (< 100 Ωm) occasioned by weathering of weak ferromagnesian minerals. However, the weak and the poor zones predominate the sedimentary setting with the poor zones concentrated in the southwestern zones of the study underlain by the sedimentary rocks. The poor to weak aquifer protective capacity ratings of the sedimentary settings indicate overburden layers devoid of argillaceous materials and conform to porous and permeable sandy sequences with high transmissivity as revealed by the high transverse unit resistance values (> 15,000 Ωm 2 ). Over 60% of the basement settings are characterized by moderate aquifer protective capacity. On the other hand, the sedimentary zones due to weak and poor protective capacity zones are more vulnerable to pollution. The trace elemental analysis shows the predominance of As, Cu, and Sb in the sedimentary zones as compared to the basement setting which corroborates the aquifer protective capacity map produced.

University, Keffi. The tools have also been shared with researchers from the University of Namibi... more University, Keffi. The tools have also been shared with researchers from the University of Namibia who are applying them to assist in their work on public health in Namibia. 2. A new interdisciplinary research-led collaboration has been established between academics in the UK and in Nigeria as a consequence of the RIGSS project. Opportunities to extend the current collaboration are being sought, including through the development of research instruments that can be applied in Nigeria as part of student-based activities. Collaboration has been extended beyond the two Universities named in the RIGSS project bid to include Nasarawa State University, Keffi. This indicates the wider relevance of this work. Work is ongoing to extend the network further, to include researchers in other networks such as the DFID/NERC/ESRC-funded UPGro Programme. The project has also enabled the researchers to establish links into the GW4 Water Securities Alliance research network. This is comprised of researchers active in this field from the Universities of Bath, Bristol, Cardiff and Exeter, some of whom attended the project's final event in Cardiff University. These links are new and are directly attributable to RIGSS award. 3. RIGSS has enabled team members to develop new partnerships with key policy and practice communities. This ranges from international organisations, such as OXFAM, Wateraid and UNICEF, to government bodies and NGOs in Nigeria, including the Lagos State Ministry of Environment, Lagos State Water Corporation and Commissioner for Water in the State Government of Nasarawa State. These have the potential to develop into long-lasting partnerships. These new partnerships remain developmental as the policy and practice debate is only gradually recognising the significance of the need to build the resilience of societies to natural and anthropogenic environmental hazards in the field of water supply. Informing this debate at such a crucial juncture is one of the key achievements of the RIGSS project and builds the foundations for strong partnerships for future activity. Work to extend the reach of the RIGSS project, and its potential impact, will continue. 4. RIGSS has defined a powerful future research agenda. This identifies research and innovation questions that integrate resource-based approaches for managing the resilience of groundwater supplies with a stronger appreciation of the influence of human agency. RIGSS team members are currently in the process of working with policy and practice communities to refine this agenda further.

Journal of Agricultural Science and Environment, 2015

The study assessed the smallholder irrigation farmers’ welfare by examining their irrigation pr... more The study assessed the smallholder irrigation farmers’ welfare by examining their irrigation practices and factor affecting their production outputs in Nigeria. Cross sectional survey was conducted and primary data were collected from 198 smallholder farmers across selected three major agro-ecological zones using a multistage sampling technique. The results revealed thatthe highest proportion of farmers using motor pump with groundwater (71%) and surface water (62%) irrigation system for farming live in houses made of cement and bricks compared to 59.1% for farmers who practice rainfed agriculture. About 81.5% of the tube wells are found among the motor pump irrigators, 30% respondents have hand dug wells. The percentage of farmers with motor pump and associated piping accessories ranges from 30% among gravity flow irrigators to 70% and 80% among surface and groundwater irrigators respectively. The analysis of factors affecting farmers productivity suggest that in order to increas...

Hydrogeology Journal, 2017

Groundwater resources are important sources of drinking water in Africa, and they are hugely impo... more Groundwater resources are important sources of drinking water in Africa, and they are hugely important in sustaining urban livelihoods and supporting a diverse range of commercial and agricultural activities. Groundwater has an important role in improving health in sub-Saharan Africa (SSA). An estimated 250 million people (40% of the total) live in urban centres across SSA. SSA has experienced a rapid expansion in urban populations since the 1950s, with increased population densities as well as expanding geographical coverage. Estimates suggest that the urban population in SSA will double between 2000 and 2030. The quality status of shallow urban groundwater resources is often very poor due to inadequate waste management and source protection, and poses a significant health risk to users, while deeper borehole sources often provide an important source of good quality drinking water. Given the growth in future demand from this finite resource, as well as potential changes in future climate in this region, a detailed understanding of both water quantity and quality is required to use this resource sustainably. This paper provides a comprehensive assessment of the water quality status, both microbial and chemical, of urban groundwater in SSA across a range of hydrogeological terrains and different groundwater point types. Lower storage basement terrains, which underlie a significant proportion of urban centres in SSA, are particularly vulnerable to contamination. The relationship between mean nitrate concentration and intrinsic aquifer pollution risk is assessed for urban centres across SSA. Current knowledge gaps are identified and future research needs highlighted.

RMZ - materials and geoenvironment, Jun 1, 2019

Groundwater flow of the basement terrains of the Ibarapa region was studied by carrying out pumpi... more Groundwater flow of the basement terrains of the Ibarapa region was studied by carrying out pumping test and measurement of borehole inventory. The view was to identify the associated aquifer systems from the time-drawdown curves, quantify the estimable hydraulic properties and develop hypothetical models for the understanding of the groundwater flow in the area underlain by diverse crystalline bedrocks. Three aquifer types were identified namely, dual, leaky and regolith. The yield of groundwater in dual and leaky aquifers that dominated terrains underlain by amphibolite and gneisses was sustainable, but the discharge of regolith aquifers mainly associated with migmatite and granite terrains declined at late pumping stage. The transmissivities of the dual and leaky aquifers were between 2.02 and 11.65 m 2 /day, while those of regolith aquifers were mostly less than 1.00 m 2 /day. The average aquifer transmissivities in m 2 /day by bedrocks were: 6.85, 2.57, 0.76 and 1.72, correspondingly. The interrelationships between transmissivities and groundwater discharge showed diverse aquifer representations, from sustainable high-yielding to unsustainable low-yielding types. Conscientious effort is, therefore, required for well construction in the area.

Earth systems and environment, Nov 8, 2017

Background The use of landfills as containment for municipal solid waste management has received ... more Background The use of landfills as containment for municipal solid waste management has received wide acceptance the world over. Its development in countries like Nigeria is constrained by high cost and scarcity of synthetic liners in the local markets. Exploration of the abundant locally available clay deposits in the country's sedimentary Basins will prove economical, provided it satisfies the standard specifications for design and construction of landfill liners. Purpose This study thus evaluates the suitability of shales from three formations (Enugu, Ameki and Imo) within Anambra Basin of Southeastern Nigeria as liner materials. Method Geotechnical tests such as particle size distribution, Atterberg's limits, compaction, coefficient of permeability and consolidation were performed on the shale samples. Geochemical analyses involving the inductively coupled plasma emission spectroscopy (ICPES) and cation exchange capacity (CEC) were also conducted; all employing standard methods. Results Based on the Unified Soil Classification System (USCS), Enugu and Imo shales contain high-plastic inorganic clay, while Ameki shales comprise low-mediumplastic inorganic clay. Coefficient of permeability result ranging from 9.12 9 10 −6 to 2.14 9 10 −6 cm/s indicates an increase above the standard specification. Expectedly, the cation exchange capacity (CEC), compressibility and plasticity index of the shales are positively related suggesting strong influence of the geotechnical properties on their sorption potentials. Overall assessment revealed that the high hydraulic conductivity and swelling potentials of the shales are not suitable for natural clay liners. Nevertheless, Enugu and Imo shales can further be stabilized chemically to the desired hydraulic conductivity of liners considering other suitable geotechnical properties and their CECs.

Sustainability of Water Quality and Ecology, Oct 1, 2014

ABSTRACT Sustaining water availability for smallholder farmers in the near future presents a grea... more ABSTRACT Sustaining water availability for smallholder farmers in the near future presents a great challenge to agricultural production in Nigeria. This study assessed the smallholder farmers’ welfare using assets possession and factors affecting their production outputs in Nigeria. A multistage sampling technique was applied in three agro-ecological zones with primary data collected and analysed using both descriptive and inferential statistics. Results show that the crop water application system practiced across the study area included rainfed system, gravity flow system, motor pump system and bucket system. A large percentage of the motor pump farmers had improved livelihood going by the type of assets they possess. Some of the irrigators were observed to use water unsustainably (not maintaining the existing system for the future generations through misuse and management of the available water resources) especially those using gravity flow system and motor pump systems, this should be discontinued in the face of the climate change affecting the country. Likewise, the use of some agro inputs such as fertilizers need to be controlled since increasing the level of these inputs was found not to translate to increased output for the farmers. Finally, the land tenure system in Nigeria does not promote smallholder farmer’s welfare as no farmer had formal title to their lands. This makes it difficult to have sufficient access to credit facilities. The policy is inimical to agricultural development in Nigeria and should be relaxed.

Applied Water Science, Jan 22, 2013

Assessments of hydrochemical quality and recharge source are critical components of sustainable g... more Assessments of hydrochemical quality and recharge source are critical components of sustainable groundwater resources evaluation and management, especially in complex weathered/fractured crystalline bedrock terrains. Assessment of the weathered/fractured basement aquifer of Ekiti area, SW-Nigeria was undertaken with emphasis on hydrochemical quality and stable isotope characterization of shallow groundwater system. The study approach involved field sampling and in situ measurements of physico-chemical parameters followed by hydrochemical and stable isotope analyses of the water samples. In situ measurements revealed EC value of 43-995 lS/cm (av 431.96 lS/cm) and total hardness of 31.3-295.1 mg/L. The pH of the water sample ranged from 7.0 to 8.9 (av 8.00). The concentrations of the major cations are in the order of Ca 2? [ K ? [ Na ? [ Mg 2? with their respective average values of 33.35, 25.61, 24.91 and 8.7 mg/L respectively while that of the anions are in the order of HCO 3-[ Cl-[ SO 4 2-[ NO 3 with their respective average values of 165.44, 31.85, 21.27 and 5.44 mg/L respectively. However, the results of stable isotope analyses revealed d 18 O value of-4.2 to-2.1 % and dD of-22.3 to-10.2 %, suggesting meteoric water source (recent precipitation water recharging the associated shallow basement aquifer) while the estimated deuterium excess of 6.80-11.00 % (av 9.6 %) suggested little or no imprint of kinetic evaporation. Furthermore, the overall hydrochemical profiles revealed the main hydrochemical facies as Ca(Mg)-HCO 3 (dominant) and Na(K)-HCO 3 (minor) water types which can be attributed to dissolution of minerals in the various rock units in the study area. Conclusively, the overall hydrochemical and stable isotope evaluations revealed a recharge predominantly derived from meteoric (rainfall) source while the corresponding low TDS is a reflection of low water-rock interaction and limited migratory history of the shallow groundwater system in the study area.

Applied Water Science, Oct 5, 2013

Due to complex and erratic nature of groundwater occurrences in crystalline basement terrains, gr... more Due to complex and erratic nature of groundwater occurrences in crystalline basement terrains, groundwater development in form of boreholes/wells without the necessary pre-drilling hydrogeological investigations usually results in failure. Therefore, there is the need for adequate characterization of aquifers and delineation of groundwater potential zones in such crystalline basement setting. This study employed the integration of multi-criteria decision analysis (MCDA), remote sensing (RS) and geographical information system (GIS) techniques to delineate groundwater potential zones in crystalline basement terrain of SW-Nigeria and validation of the result with existing borehole/well yield data. The study approach involved integration of nine different thematic layers (geology, rainfall geomorphology, soil, drainage density, lineament density, landuse, slope and drainage proximity) based on weights assignment and normalization with respect to the relative contribution of the different themes to groundwater occurrence using Saaty's analytic hierarchy approach. Following weigh normalization and ranking, the thematic maps were integrated using ArcGIS 10.0 software to generate the overall groundwater potential map for the study area. The result revealed that the study area can be categorized into three different groundwater potential zones: high, medium and low. Greater portion of the study area (84,121.8 km 2) representing about 78 % of the total area, fall within the medium groundwater potential zone which are generally underlain by medium-porphyritic granite, biotite-hornblende granite and granite gneiss bedrock settings. About 18,239.7 km 2 (17 %) fall under high groundwater potential zone which are characterized by weathered/fractured quartzite, quartz-schist, amphibolite schist and phyllite bedrock settings. However, areas of low groundwater potentials constitute only 3 % (3,416.54 km 2) of the total study area and are mostly underlain by migmatite, banded and augen gneiss bedrock settings. Subsequent validation with boreholes/well yield data revealed a good correlation with respect to the observed groundwater potential zonation. Wells/boreholes with yields greater than [150 m 3 /day are generally characteristic of areas with high groundwater potential while those with yields of 75-150 and \75 m 3 /day are typical of areas with medium and low groundwater potentials, respectively. The validation clearly highlights the efficacy of the integrated MCDA, RS and GIS methods employed in this study as useful modern approach for proper groundwater resources evaluation; providing quick prospective guides for groundwater exploration and exploitation in such crystalline basement settings.

Journal of Water Resource and Protection, 2014

Journal of Mining and Geology, Oct 10, 2006

Global Journal of Geological Sciences, Mar 17, 2017

Physiochemical assessment of shallow groundwater in Gboloko area was carried out to determine its... more Physiochemical assessment of shallow groundwater in Gboloko area was carried out to determine its suitability for drinking and irrigation purposes. Eighteen (18) groundwater samples were collected from different rural communities' wells and subjected field measurements of physical parameters followed by chemical analyses using ICP-MS, ICP-ES, Calorimetry and Turbimetry methods. The results show that pH of the groundwater ranged from 5.1 to 8.6 (mean 6.6) which indicates the groundwater is slightly acidic and slightly alkaline. EC and TDS varied from 60 to1367mg/L (mean 277.4mg/L) and 53 to 995mg/L (mean 206.5mg/L) respectively. The concentration of major cations were in the order of Ca 2+ >Na + > Mg 2+ > K + while that of anion were in the order of HCO 3->Cl-> SO 4-> NO 3-.Five hydrochemical facies were delineated from Piper plot; they are CaHCO 3, CaNaHCO 3 , CaMgCl, CaCl, and NaHCO 3 water type. CaHCO 3 water is the dominant facies which represents water of recharge zone while CaNaHCO3 and CaCl are the least. The presence of NaHCO3 CaNaHCO3, and CaMgCl water type shows hydrochemical processes such as ion exchange and linear mixing. The drinking water quality assessment indicates the values for all the hydrochemical parameters are within the maximum permissible standard by WHO, 2006 except for two locations where nitrate concentrations are above the guideline value. The nitrate contamination observed at those locations may be attributed to leachates from domestic wastes and agricultural activities. Although nitrate contamination was expected to be rampant in groundwater of the area Irrigation water quality indices showed that the groundwater is ranged from mostly suitable to unsuitable.

Geomaterials, 2015

The degree of structural damage of the Louga-Ouarack-Ndoyene R31 regional road was surveyed using... more The degree of structural damage of the Louga-Ouarack-Ndoyene R31 regional road was surveyed using Lacroix deflectographe and geotechnical testing, in order to recommend possible rehabilitation measures aimed at maintaining the high level of service over the projected life span of the road. The data processing and interpretation were essentially based on the French standards and specifications, through which synthetic variables were generated with a qualitative significance and on the basis of which the extent of repairs and rehabilitation works to be undertaken were suggested. The decision grid thus produced, revealed road structure quality indices of mostly Q3, Q4, and Q5 types for a segment length of 36.954 km (equivalent to some 69.44% of the total road section), which justifies some major reinforcement works. The remaining part of the road section (nearly 30.56% with road quality indices ≤ Q2) is still in acceptable condition, requiring only some minor maintenance works. The rehabilitation costs were estimated to be of the order of 5,352,000,000 (five billion three hundred fifty-two million) CFA francs, based on local market price conditions.

Journal of African Earth Sciences, Dec 1, 2006

 In this study, an assessment of the lithogenic concentrations of trace metals in soils and sapr... more  In this study, an assessment of the lithogenic concentrations of trace metals in soils and saprolite over basement rock units in Ibadan, SW-Nigeria is presented in respect of bedrock types and geochemical controls on the weathering-associated release of trace metals. Consequently, soil, weathered and fresh rock samples from the Precambrian Basement of SW Nigeria were collected from three different bedrock units within Ibadan metropolis and subjected to mineralogical and geochemical analyses. The analytical results revealed major proportions of oxides in the range of 18-20% Al2O3, 2-6% Na2O and 1-6% K2O for weathered profiles over granite-gneiss and pegmatite units, compared to 2-3% Al2O3, <0.5% Na2O and <1.0% K2O over schist-quartzite. For the trace elements, weathered profiles on granite-gneiss and schist-quartzite settings exhibit similar enrichment trends (enrichment factor, EF ⩾l) for most of the trace elements, unlike the pegmatite bedrock. However, enrichments are relatively greater in the top soil unit compared to the intermediate saprolite unit, especially for Pb, Ni, Zn, Cr, Co, Rb, Sr and Ba, a situation attributed to leaching and redistribution within the weathered profiles through pedogenetic process and percolating groundwater.  Furthermore, the estimated weathering indices using Ruxton Ratio (RR = {SiO2/Al2O3}) and Chemical Index of Alteration (CIA = 100{Al2O3/[Al2O3 + CaO + Na2O + K2O]}) revealed RR of 2.9-3.7 and CIA of 54-73% for granite-gneiss and pegmatite units, implying medium levels of weathering, compared to RR of 30.8-35.5 and CIA of >60% for schist-quartzite units, which suggest weak chemical weathering. Also, the estimated high percentage loss, especially for Pb, Rb, Sr, Ba relative to the bedrocks, shows that the trace elements can be mobilized within the weathering profiles even at a low degree of chemical weathering. Such weathering-induced release of trace metals is of environmental significance as natural lithogenic input sources and as background reference for future monitoring of possible human/anthropogenic impacts.

Environmental Research Letters, Feb 16, 2021

Applied Geochemistry, Sep 1, 2004

... Field measurements included pH, temperature and electrical conductivity (EC) while laboratory... more ... Field measurements included pH, temperature and electrical conductivity (EC) while laboratory analyses of the samples included Na + , K + , Ca 2+ , Mg 2+ , Ba 2+ , Sr 2+ , HCO 3 − Cl − , SO 4 2− and Br − . ... Decsription, Temp. pH, EC, TDI, Ca, Mg, Na, K, Ba, Sr, HCO 3, Cl, SO 4, Br ...

Hydrogeology Journal, Nov 28, 2012

Although shallow groundwater (<50 mbgl) sustains the vast majority of improved drinking water sup... more Although shallow groundwater (<50 mbgl) sustains the vast majority of improved drinking water supplies in rural Africa, there is little information on how resilient this resource may be to future changes in climate. This study presents results of a groundwater survey using stable isotopes, CFCs, SF 6 , and 3 H across different climatic zones (annual rainfall 400-2000 mm/y) in West Africa. The purpose was to quantify the residence times of shallow groundwaters in sedimentary and basement aquifers, and investigate the relationship between groundwater resources and climate. Stable-isotope results indicate that most shallow groundwaters sampled are recharged rapidly following rainfall, showing little evidence of evaporation prior to recharge. Chloride mass balance results indicate that within the arid areas (<400 mm annual rainfall) there is recharge of up to 20 mm/y. Age tracers showed that most groundwaters have mean residence times (MRTs) of 32-65 years, with comparable

African Journal of Science and Technology, 2010

Environmental Earth Sciences, 2021

The poor quality and inconsistent nature of most surface water supply in arid and semi-arid regio... more The poor quality and inconsistent nature of most surface water supply in arid and semi-arid regions of the world has increased the reliance on groundwater resources. However, the susceptibility of groundwater to anthropogenic pollution in most cities and rural communities in Nigeria has become a major source of concern. In this study, the protective capacity of the aquifers in parts of the Bauchi State, Northeastern, Nigeria, from surface contamination was investigated in light of the geoelectrical characteristics of the overburden materials for sustainable management of the resources. This study applied a geographical information system (GIS) technique to secondary geoelectrical parameters (Dar-Zarrouk) derived from 94 vertical electrical soundings (VES) to delineate aquifer vulnerability zones. Five different thematic maps (topsoil longitudinal unit conductance, total overburden longitudinal unit conductance, total transverse unit resistance, coefficient of anisotropy, and total overburden isopach) were developed. Suitable weights were assigned to the thematic maps based on their relative influence on the protection of groundwater systems in the area. Subsequently, the ranks of the subclasses of the themes were reclassified based on their respective suitability before the thematic maps were integrated using ArcGIS 10.3 software to generate the overall aquifer protective capacity map of the study area. To validate the map, water samples were collected from 40 wells and trace elements (e.g., Ni, Cu, Sb, Cr, and As) were analyzed. The study area was categorized into three aquifer vulnerability zones: moderate (32.4%), weak/fair (54.5%), and low/poor (13.1%). Moderate zones with limited portions of fair/weak zones were the predominant zones within the basement setting. This reflects the occurrence of clayey saprolitic units within the basement terrain (< 100 Ωm) occasioned by weathering of weak ferromagnesian minerals. However, the weak and the poor zones predominate the sedimentary setting with the poor zones concentrated in the southwestern zones of the study underlain by the sedimentary rocks. The poor to weak aquifer protective capacity ratings of the sedimentary settings indicate overburden layers devoid of argillaceous materials and conform to porous and permeable sandy sequences with high transmissivity as revealed by the high transverse unit resistance values (> 15,000 Ωm 2 ). Over 60% of the basement settings are characterized by moderate aquifer protective capacity. On the other hand, the sedimentary zones due to weak and poor protective capacity zones are more vulnerable to pollution. The trace elemental analysis shows the predominance of As, Cu, and Sb in the sedimentary zones as compared to the basement setting which corroborates the aquifer protective capacity map produced.

University, Keffi. The tools have also been shared with researchers from the University of Namibi... more University, Keffi. The tools have also been shared with researchers from the University of Namibia who are applying them to assist in their work on public health in Namibia. 2. A new interdisciplinary research-led collaboration has been established between academics in the UK and in Nigeria as a consequence of the RIGSS project. Opportunities to extend the current collaboration are being sought, including through the development of research instruments that can be applied in Nigeria as part of student-based activities. Collaboration has been extended beyond the two Universities named in the RIGSS project bid to include Nasarawa State University, Keffi. This indicates the wider relevance of this work. Work is ongoing to extend the network further, to include researchers in other networks such as the DFID/NERC/ESRC-funded UPGro Programme. The project has also enabled the researchers to establish links into the GW4 Water Securities Alliance research network. This is comprised of researchers active in this field from the Universities of Bath, Bristol, Cardiff and Exeter, some of whom attended the project's final event in Cardiff University. These links are new and are directly attributable to RIGSS award. 3. RIGSS has enabled team members to develop new partnerships with key policy and practice communities. This ranges from international organisations, such as OXFAM, Wateraid and UNICEF, to government bodies and NGOs in Nigeria, including the Lagos State Ministry of Environment, Lagos State Water Corporation and Commissioner for Water in the State Government of Nasarawa State. These have the potential to develop into long-lasting partnerships. These new partnerships remain developmental as the policy and practice debate is only gradually recognising the significance of the need to build the resilience of societies to natural and anthropogenic environmental hazards in the field of water supply. Informing this debate at such a crucial juncture is one of the key achievements of the RIGSS project and builds the foundations for strong partnerships for future activity. Work to extend the reach of the RIGSS project, and its potential impact, will continue. 4. RIGSS has defined a powerful future research agenda. This identifies research and innovation questions that integrate resource-based approaches for managing the resilience of groundwater supplies with a stronger appreciation of the influence of human agency. RIGSS team members are currently in the process of working with policy and practice communities to refine this agenda further.

Journal of Agricultural Science and Environment, 2015

The study assessed the smallholder irrigation farmers’ welfare by examining their irrigation pr... more The study assessed the smallholder irrigation farmers’ welfare by examining their irrigation practices and factor affecting their production outputs in Nigeria. Cross sectional survey was conducted and primary data were collected from 198 smallholder farmers across selected three major agro-ecological zones using a multistage sampling technique. The results revealed thatthe highest proportion of farmers using motor pump with groundwater (71%) and surface water (62%) irrigation system for farming live in houses made of cement and bricks compared to 59.1% for farmers who practice rainfed agriculture. About 81.5% of the tube wells are found among the motor pump irrigators, 30% respondents have hand dug wells. The percentage of farmers with motor pump and associated piping accessories ranges from 30% among gravity flow irrigators to 70% and 80% among surface and groundwater irrigators respectively. The analysis of factors affecting farmers productivity suggest that in order to increas...

Hydrogeology Journal, 2017

Groundwater resources are important sources of drinking water in Africa, and they are hugely impo... more Groundwater resources are important sources of drinking water in Africa, and they are hugely important in sustaining urban livelihoods and supporting a diverse range of commercial and agricultural activities. Groundwater has an important role in improving health in sub-Saharan Africa (SSA). An estimated 250 million people (40% of the total) live in urban centres across SSA. SSA has experienced a rapid expansion in urban populations since the 1950s, with increased population densities as well as expanding geographical coverage. Estimates suggest that the urban population in SSA will double between 2000 and 2030. The quality status of shallow urban groundwater resources is often very poor due to inadequate waste management and source protection, and poses a significant health risk to users, while deeper borehole sources often provide an important source of good quality drinking water. Given the growth in future demand from this finite resource, as well as potential changes in future climate in this region, a detailed understanding of both water quantity and quality is required to use this resource sustainably. This paper provides a comprehensive assessment of the water quality status, both microbial and chemical, of urban groundwater in SSA across a range of hydrogeological terrains and different groundwater point types. Lower storage basement terrains, which underlie a significant proportion of urban centres in SSA, are particularly vulnerable to contamination. The relationship between mean nitrate concentration and intrinsic aquifer pollution risk is assessed for urban centres across SSA. Current knowledge gaps are identified and future research needs highlighted.

RMZ - materials and geoenvironment, Jun 1, 2019

Groundwater flow of the basement terrains of the Ibarapa region was studied by carrying out pumpi... more Groundwater flow of the basement terrains of the Ibarapa region was studied by carrying out pumping test and measurement of borehole inventory. The view was to identify the associated aquifer systems from the time-drawdown curves, quantify the estimable hydraulic properties and develop hypothetical models for the understanding of the groundwater flow in the area underlain by diverse crystalline bedrocks. Three aquifer types were identified namely, dual, leaky and regolith. The yield of groundwater in dual and leaky aquifers that dominated terrains underlain by amphibolite and gneisses was sustainable, but the discharge of regolith aquifers mainly associated with migmatite and granite terrains declined at late pumping stage. The transmissivities of the dual and leaky aquifers were between 2.02 and 11.65 m 2 /day, while those of regolith aquifers were mostly less than 1.00 m 2 /day. The average aquifer transmissivities in m 2 /day by bedrocks were: 6.85, 2.57, 0.76 and 1.72, correspondingly. The interrelationships between transmissivities and groundwater discharge showed diverse aquifer representations, from sustainable high-yielding to unsustainable low-yielding types. Conscientious effort is, therefore, required for well construction in the area.

Earth systems and environment, Nov 8, 2017

Background The use of landfills as containment for municipal solid waste management has received ... more Background The use of landfills as containment for municipal solid waste management has received wide acceptance the world over. Its development in countries like Nigeria is constrained by high cost and scarcity of synthetic liners in the local markets. Exploration of the abundant locally available clay deposits in the country's sedimentary Basins will prove economical, provided it satisfies the standard specifications for design and construction of landfill liners. Purpose This study thus evaluates the suitability of shales from three formations (Enugu, Ameki and Imo) within Anambra Basin of Southeastern Nigeria as liner materials. Method Geotechnical tests such as particle size distribution, Atterberg's limits, compaction, coefficient of permeability and consolidation were performed on the shale samples. Geochemical analyses involving the inductively coupled plasma emission spectroscopy (ICPES) and cation exchange capacity (CEC) were also conducted; all employing standard methods. Results Based on the Unified Soil Classification System (USCS), Enugu and Imo shales contain high-plastic inorganic clay, while Ameki shales comprise low-mediumplastic inorganic clay. Coefficient of permeability result ranging from 9.12 9 10 −6 to 2.14 9 10 −6 cm/s indicates an increase above the standard specification. Expectedly, the cation exchange capacity (CEC), compressibility and plasticity index of the shales are positively related suggesting strong influence of the geotechnical properties on their sorption potentials. Overall assessment revealed that the high hydraulic conductivity and swelling potentials of the shales are not suitable for natural clay liners. Nevertheless, Enugu and Imo shales can further be stabilized chemically to the desired hydraulic conductivity of liners considering other suitable geotechnical properties and their CECs.

Sustainability of Water Quality and Ecology, Oct 1, 2014

ABSTRACT Sustaining water availability for smallholder farmers in the near future presents a grea... more ABSTRACT Sustaining water availability for smallholder farmers in the near future presents a great challenge to agricultural production in Nigeria. This study assessed the smallholder farmers’ welfare using assets possession and factors affecting their production outputs in Nigeria. A multistage sampling technique was applied in three agro-ecological zones with primary data collected and analysed using both descriptive and inferential statistics. Results show that the crop water application system practiced across the study area included rainfed system, gravity flow system, motor pump system and bucket system. A large percentage of the motor pump farmers had improved livelihood going by the type of assets they possess. Some of the irrigators were observed to use water unsustainably (not maintaining the existing system for the future generations through misuse and management of the available water resources) especially those using gravity flow system and motor pump systems, this should be discontinued in the face of the climate change affecting the country. Likewise, the use of some agro inputs such as fertilizers need to be controlled since increasing the level of these inputs was found not to translate to increased output for the farmers. Finally, the land tenure system in Nigeria does not promote smallholder farmer’s welfare as no farmer had formal title to their lands. This makes it difficult to have sufficient access to credit facilities. The policy is inimical to agricultural development in Nigeria and should be relaxed.

Applied Water Science, Jan 22, 2013

Assessments of hydrochemical quality and recharge source are critical components of sustainable g... more Assessments of hydrochemical quality and recharge source are critical components of sustainable groundwater resources evaluation and management, especially in complex weathered/fractured crystalline bedrock terrains. Assessment of the weathered/fractured basement aquifer of Ekiti area, SW-Nigeria was undertaken with emphasis on hydrochemical quality and stable isotope characterization of shallow groundwater system. The study approach involved field sampling and in situ measurements of physico-chemical parameters followed by hydrochemical and stable isotope analyses of the water samples. In situ measurements revealed EC value of 43-995 lS/cm (av 431.96 lS/cm) and total hardness of 31.3-295.1 mg/L. The pH of the water sample ranged from 7.0 to 8.9 (av 8.00). The concentrations of the major cations are in the order of Ca 2? [ K ? [ Na ? [ Mg 2? with their respective average values of 33.35, 25.61, 24.91 and 8.7 mg/L respectively while that of the anions are in the order of HCO 3-[ Cl-[ SO 4 2-[ NO 3 with their respective average values of 165.44, 31.85, 21.27 and 5.44 mg/L respectively. However, the results of stable isotope analyses revealed d 18 O value of-4.2 to-2.1 % and dD of-22.3 to-10.2 %, suggesting meteoric water source (recent precipitation water recharging the associated shallow basement aquifer) while the estimated deuterium excess of 6.80-11.00 % (av 9.6 %) suggested little or no imprint of kinetic evaporation. Furthermore, the overall hydrochemical profiles revealed the main hydrochemical facies as Ca(Mg)-HCO 3 (dominant) and Na(K)-HCO 3 (minor) water types which can be attributed to dissolution of minerals in the various rock units in the study area. Conclusively, the overall hydrochemical and stable isotope evaluations revealed a recharge predominantly derived from meteoric (rainfall) source while the corresponding low TDS is a reflection of low water-rock interaction and limited migratory history of the shallow groundwater system in the study area.

Applied Water Science, Oct 5, 2013

Due to complex and erratic nature of groundwater occurrences in crystalline basement terrains, gr... more Due to complex and erratic nature of groundwater occurrences in crystalline basement terrains, groundwater development in form of boreholes/wells without the necessary pre-drilling hydrogeological investigations usually results in failure. Therefore, there is the need for adequate characterization of aquifers and delineation of groundwater potential zones in such crystalline basement setting. This study employed the integration of multi-criteria decision analysis (MCDA), remote sensing (RS) and geographical information system (GIS) techniques to delineate groundwater potential zones in crystalline basement terrain of SW-Nigeria and validation of the result with existing borehole/well yield data. The study approach involved integration of nine different thematic layers (geology, rainfall geomorphology, soil, drainage density, lineament density, landuse, slope and drainage proximity) based on weights assignment and normalization with respect to the relative contribution of the different themes to groundwater occurrence using Saaty's analytic hierarchy approach. Following weigh normalization and ranking, the thematic maps were integrated using ArcGIS 10.0 software to generate the overall groundwater potential map for the study area. The result revealed that the study area can be categorized into three different groundwater potential zones: high, medium and low. Greater portion of the study area (84,121.8 km 2) representing about 78 % of the total area, fall within the medium groundwater potential zone which are generally underlain by medium-porphyritic granite, biotite-hornblende granite and granite gneiss bedrock settings. About 18,239.7 km 2 (17 %) fall under high groundwater potential zone which are characterized by weathered/fractured quartzite, quartz-schist, amphibolite schist and phyllite bedrock settings. However, areas of low groundwater potentials constitute only 3 % (3,416.54 km 2) of the total study area and are mostly underlain by migmatite, banded and augen gneiss bedrock settings. Subsequent validation with boreholes/well yield data revealed a good correlation with respect to the observed groundwater potential zonation. Wells/boreholes with yields greater than [150 m 3 /day are generally characteristic of areas with high groundwater potential while those with yields of 75-150 and \75 m 3 /day are typical of areas with medium and low groundwater potentials, respectively. The validation clearly highlights the efficacy of the integrated MCDA, RS and GIS methods employed in this study as useful modern approach for proper groundwater resources evaluation; providing quick prospective guides for groundwater exploration and exploitation in such crystalline basement settings.

Journal of Water Resource and Protection, 2014

Journal of Mining and Geology, Oct 10, 2006

Global Journal of Geological Sciences, Mar 17, 2017

Physiochemical assessment of shallow groundwater in Gboloko area was carried out to determine its... more Physiochemical assessment of shallow groundwater in Gboloko area was carried out to determine its suitability for drinking and irrigation purposes. Eighteen (18) groundwater samples were collected from different rural communities' wells and subjected field measurements of physical parameters followed by chemical analyses using ICP-MS, ICP-ES, Calorimetry and Turbimetry methods. The results show that pH of the groundwater ranged from 5.1 to 8.6 (mean 6.6) which indicates the groundwater is slightly acidic and slightly alkaline. EC and TDS varied from 60 to1367mg/L (mean 277.4mg/L) and 53 to 995mg/L (mean 206.5mg/L) respectively. The concentration of major cations were in the order of Ca 2+ >Na + > Mg 2+ > K + while that of anion were in the order of HCO 3->Cl-> SO 4-> NO 3-.Five hydrochemical facies were delineated from Piper plot; they are CaHCO 3, CaNaHCO 3 , CaMgCl, CaCl, and NaHCO 3 water type. CaHCO 3 water is the dominant facies which represents water of recharge zone while CaNaHCO3 and CaCl are the least. The presence of NaHCO3 CaNaHCO3, and CaMgCl water type shows hydrochemical processes such as ion exchange and linear mixing. The drinking water quality assessment indicates the values for all the hydrochemical parameters are within the maximum permissible standard by WHO, 2006 except for two locations where nitrate concentrations are above the guideline value. The nitrate contamination observed at those locations may be attributed to leachates from domestic wastes and agricultural activities. Although nitrate contamination was expected to be rampant in groundwater of the area Irrigation water quality indices showed that the groundwater is ranged from mostly suitable to unsuitable.

Geomaterials, 2015

The degree of structural damage of the Louga-Ouarack-Ndoyene R31 regional road was surveyed using... more The degree of structural damage of the Louga-Ouarack-Ndoyene R31 regional road was surveyed using Lacroix deflectographe and geotechnical testing, in order to recommend possible rehabilitation measures aimed at maintaining the high level of service over the projected life span of the road. The data processing and interpretation were essentially based on the French standards and specifications, through which synthetic variables were generated with a qualitative significance and on the basis of which the extent of repairs and rehabilitation works to be undertaken were suggested. The decision grid thus produced, revealed road structure quality indices of mostly Q3, Q4, and Q5 types for a segment length of 36.954 km (equivalent to some 69.44% of the total road section), which justifies some major reinforcement works. The remaining part of the road section (nearly 30.56% with road quality indices ≤ Q2) is still in acceptable condition, requiring only some minor maintenance works. The rehabilitation costs were estimated to be of the order of 5,352,000,000 (five billion three hundred fifty-two million) CFA francs, based on local market price conditions.

Journal of African Earth Sciences, Dec 1, 2006

 In this study, an assessment of the lithogenic concentrations of trace metals in soils and sapr... more  In this study, an assessment of the lithogenic concentrations of trace metals in soils and saprolite over basement rock units in Ibadan, SW-Nigeria is presented in respect of bedrock types and geochemical controls on the weathering-associated release of trace metals. Consequently, soil, weathered and fresh rock samples from the Precambrian Basement of SW Nigeria were collected from three different bedrock units within Ibadan metropolis and subjected to mineralogical and geochemical analyses. The analytical results revealed major proportions of oxides in the range of 18-20% Al2O3, 2-6% Na2O and 1-6% K2O for weathered profiles over granite-gneiss and pegmatite units, compared to 2-3% Al2O3, <0.5% Na2O and <1.0% K2O over schist-quartzite. For the trace elements, weathered profiles on granite-gneiss and schist-quartzite settings exhibit similar enrichment trends (enrichment factor, EF ⩾l) for most of the trace elements, unlike the pegmatite bedrock. However, enrichments are relatively greater in the top soil unit compared to the intermediate saprolite unit, especially for Pb, Ni, Zn, Cr, Co, Rb, Sr and Ba, a situation attributed to leaching and redistribution within the weathered profiles through pedogenetic process and percolating groundwater.  Furthermore, the estimated weathering indices using Ruxton Ratio (RR = {SiO2/Al2O3}) and Chemical Index of Alteration (CIA = 100{Al2O3/[Al2O3 + CaO + Na2O + K2O]}) revealed RR of 2.9-3.7 and CIA of 54-73% for granite-gneiss and pegmatite units, implying medium levels of weathering, compared to RR of 30.8-35.5 and CIA of >60% for schist-quartzite units, which suggest weak chemical weathering. Also, the estimated high percentage loss, especially for Pb, Rb, Sr, Ba relative to the bedrocks, shows that the trace elements can be mobilized within the weathering profiles even at a low degree of chemical weathering. Such weathering-induced release of trace metals is of environmental significance as natural lithogenic input sources and as background reference for future monitoring of possible human/anthropogenic impacts.

Environmental Research Letters, Feb 16, 2021

Applied Geochemistry, Sep 1, 2004

... Field measurements included pH, temperature and electrical conductivity (EC) while laboratory... more ... Field measurements included pH, temperature and electrical conductivity (EC) while laboratory analyses of the samples included Na + , K + , Ca 2+ , Mg 2+ , Ba 2+ , Sr 2+ , HCO 3 − Cl − , SO 4 2− and Br − . ... Decsription, Temp. pH, EC, TDI, Ca, Mg, Na, K, Ba, Sr, HCO 3, Cl, SO 4, Br ...

Hydrogeology Journal, Nov 28, 2012

Although shallow groundwater (<50 mbgl) sustains the vast majority of improved drinking water sup... more Although shallow groundwater (<50 mbgl) sustains the vast majority of improved drinking water supplies in rural Africa, there is little information on how resilient this resource may be to future changes in climate. This study presents results of a groundwater survey using stable isotopes, CFCs, SF 6 , and 3 H across different climatic zones (annual rainfall 400-2000 mm/y) in West Africa. The purpose was to quantify the residence times of shallow groundwaters in sedimentary and basement aquifers, and investigate the relationship between groundwater resources and climate. Stable-isotope results indicate that most shallow groundwaters sampled are recharged rapidly following rainfall, showing little evidence of evaporation prior to recharge. Chloride mass balance results indicate that within the arid areas (<400 mm annual rainfall) there is recharge of up to 20 mm/y. Age tracers showed that most groundwaters have mean residence times (MRTs) of 32-65 years, with comparable

Three major rock types are present in Nigeria: igneous, metamorphic and sedimentary. Igneous and ... more Three major rock types are present in Nigeria: igneous, metamorphic and sedimentary. Igneous and metamorphic rocks constitute the Precambrian Basement Complex which is the oldest, crystalline, solid physical foundation of the country. Sedimentary rocks of the Cretaceous and Cenozoic age fill up the basins, which are depressions within the basement landmass. The Basement Complex and the sedimentary basins are equally dispersed in Nigeria. Quaternary to Recent age alluvial deposits occur along the main river valleys as thin and discontinuous sandy beds to thick sedimentary units up to 15 km wide and 15-30 m thick along the channels of rivers Niger and Benue, as well as along the courses of major ephemeral streams and fadamas, especially in the northern parts of Nigeria. The diverse geology of Nigeria offers opportunities for the exploitation of varied mineral deposits contained in different rock units. Abundant mineral deposits occur in all components of Nigerian geology with mineral deposits of economic significance that include gold, iron ore, cassiterite, columbite, wolframite, pyrochlore, monazite, marble, coal, limestone, clays, barites, lead-zinc, etc. The geological, structural and tectonic settings of different rock units have significant implications on the geomorphological evolution of the landscapes in Nigeria. In addition, a number of the associated geological-geomorphic features and scenery have considerable aesthetic and touristic potential, which in some cases combines with cultural importance.