ATBU Journal of Environmental Technology

Awareness of the Impact of Digital Carbon Footprint in Plateau State, Nigeria

2026-08-03T11:37:45+00:00

Nigeria's rapid digital growth has led to environmental issues related to information and communication technology that are often overlooked. This study examines how aware residents of Plateau State are of their digital carbon footprint and its contribution to global
warming. Researchers purposively surveyed 300 digitally active adults, most of whom are well-educated and employed, to assess their knowledge and behaviours. Results reveal that 40.7% have a moderate understanding of digital environmental impacts, yet many do not
know how to properly dispose of used electronics. 83% are unaware of e-waste regulations, which increases health risks due to toxic emissions from informal disposal methods. Despite over 68% spending more than four hours online daily, the state's digital infrastructure still depends on diesel-powered energy because of unreliable electricity from the grid. Additionally, 95.7% of participants expressed a willingness to reduce their digital carbon footprint if given adequate information, and 60% supported a shared responsibility model involving government, technology companies, and individual users. The study concludes that current awareness levels are insufficient to promote digital sustainability. Recommendations include enforcing state-level e-waste regulations, transitioning telecommunications infrastructure to renewable energy sources, and launching targeted public awareness campaigns to encourage digital sobriety. These findings highlight the urgent need to align digital growth with climate resilience objectives to mitigate Nigeria's digital ecological costs.

Investigation of the Key Factors for Implementing Sustainable Green Cleaning Services in Malaysia

2026-08-03T11:42:14+00:00

Poor indoor air quality, climate change, and environmental degradation are worsening. The cleaning industry, through its conventional practices, particularly its use of traditional cleaning chemicals and the processes it adopts, contributes to these issues. Green cleaningtechnology safeguards human health without endangering the environment and can address concerns exacerbated by conventional cleaning methods. Despite their potential benefits, green cleaning initiatives face sustainability challenges because of implementation problems. This article aims to verify the key factors that constitute a model for measuring the implementation of sustainable green cleaning services in Malaysia. Data were collected from Malaysian cleaning contractors, facilities managers, and cleaning service users through a questionnaire using purposive and stratified sampling techniques. The adoption of these sampling methods was born of the need to engage populations directly involved in cleaning services to collect rich information through purposive sampling, and the quest to reduce biasand improve the generalisation of findings through the stratification of the study area. The study population and sample size were 862 and 500, respectively. The Statistical Package for Social Science (SPSS), Exploratory Factor Analysis, Confirmatory Factor Analysis (CFA), and Analysis of Moment Structures (AMOS) were used to analyse the data. The results showed that the primary factors influencing sustainable green cleaning services implementation are physical resources and human resources, which exhibit high correlations and are statistically significant with critical success factors. The fit indices of the measurement model indicated a good fit, P = .000, x2/df = 1.218, GFI = 0.951, NFI=0.969, TLI=0.993, and RMSEA = 0.021. The implications are that stakeholders in the cleaning industry are encouraged to allocate the necessary time and resources to implement a comprehensive, sustainable green cleaning project, focusing on these essential factors.

Development of a Precast Concrete Anaerobic Biogas Digester Using Typha Biomass Feedstock

2026-08-03T11:47:28+00:00

The study developed and evaluated the performance of a precast concrete anaerobic digester for biogas production using Typha biomass as a sustainable feedstock. Two digester models (small- and large-scale) were developed and evaluated under field conditions using 18
treatment combinations of two, three, and four component Typha mixtures in an RCBD arrangement. Key parameters, including biogas volume, methane yield, pH, and temperature, were monitored, and statistical analyses (ANOVA and Duncan's Multiple Range Test) were
applied. The leaf–root mixture produced the highest biogas volume in both small-scale (10,486 ml; 436.91 ml/g vs) and large-scale (94,300 ml; 196 ml/g vs) digesters, while treatments without rumen inoculant in a small model digester yielded significantly lower outputs (2111.667 ml; 87.98 ml/g vs), confirming the importance of microbial inoculation. Among multi-component mixtures, stem–root–rhizome and spike–leaf–rhizome–root combinations performed best, with consistent trends observed across scales. The results demonstrate the influence of substrate composition and inoculation on digestion efficiency and confirm the scalability of the system for decentralized applications. The study presents a novel integration of precast concrete digester design with Typha biomass utilization, offering a cost-effective and sustainable approach for renewable energy generation and invasive biomass management.

Assessing Climate-Smart Landscape Performance for Environmental Resilience in Daura LGA, Northern Nigeria

2026-08-03T11:51:01+00:00

Hydro-climatic stressors, including flash flooding, wind erosion, and extreme heat,
increasingly destabilize semi-arid settlements in Northern Nigeria. This study evaluates the
performance of Climate-Smart Landscape (CSL) interventions, specifically vegetated
stormwater corridors, rehabilitated shelterbelts, and peri-settlement buffers, in Daura LGA.
Using a mixed-methods approach (microclimatic monitoring, hydrological infiltration tests,
and a 212-household survey), the research compares biophysical efficiency and socioenvironmental outcomes against conventional "grey" infrastructure. Results show that
vegetated corridors achieved 81% Runoff Retention Efficiency (RRE), vastly outperforming
the 10–15% retention of concrete drains. Additionally, shelterbelts reduced wind speeds by
52%, and buffers lowered daytime temperatures by 3.2°C. These gains align with high
community validation, including 76% agreement on improved thermal comfort. The study
confirms that CSLinterventions are vital ecological regulators and recommends transitioning
toward hybrid "green grey" infrastructure and community-led maintenance to enhance
climate-adaptive capacity in the Sudan–Sahel belt.

Engineering Performance of Sisal Fibre Reinforced RHA–Metakaolin Based Structural Lightweight Geopolymer Concrete Incorporating Pumice Aggregate

2026-08-04T11:17:07+00:00

The growing need to reduce carbon emissions associated with ordinary Portland cement
(OPC) production has increased interest in geopolymer binders derived from industrial and
agricultural by-products. This study investigates the engineering and durability performance
of sisal fibre reinforced structural lightweight geopolymer concrete produced using rice husk
ash (RHA) and metakaolin (MK) as blended binders, pumice as lightweight coarse aggregate,
and sodium carbonate as the alkaline activator. A binary binder consisting of 70% RHA and
30% MK was used, while natural gravel was replaced with pumice aggregate at 0%, 25%,
50%, 75%, and 100% by volume. Sisal fibre was incorporated at a 0.5% volume fraction.
Fresh and hardened properties were evaluated through slump, bulk density, compressive
strength, splitting tensile strength, and flexural strength tests up to 56 days of curing.
Durability performance was assessed using water absorption and abrasion resistance tests,
while scanning electron microscopy (SEM) was used to examine microstructural
characteristics and fibre–matrix interaction. Results showed that increasing pumice content
reduced workability and compressive strength due to higher porosity and weaker aggregate
bonding. However, mixtures containing up to 50% pumice achieved compressive strengths
suitable for structural lightweight concrete, with densities within the structural lightweight
concrete range (<2000 kg/m³). Sisal fibre enhanced tensile and flexural strengths through
improved crack bridging and post-cracking resistance. The study demonstrates that
RHA–MK based geopolymer concrete incorporating pumice and sisal fibre provides a
sustainable alternative to conventional OPC-based structural lightweight concrete.

Green Procurement Practices in Abuja's Public Building Sector: An Empirical Analysis of Adoption Rates and Implementation Strategies

2026-08-03T11:55:22+00:00

Green procurement has become an important tool for sustainable development by embedding environmental concerns into purchasing decisions. This study aims to analyse the adoption rates and implementation strategies of green procurement practices in Abuja’s public building sector. While many governments and organizations worldwide are adopting these practices to reduce ecological impacts, Nigeria’s level of adoption and effective implementation remains unclear and insufficiently studied. Data were collected quantitatively through questionnaires administered to stakeholders, yielding 334 valid responses. These responses were examined using descriptive statistics in IBM SPSS (version 25). Mean scores, standard deviations, and the Implementation Index (II) formula were employed to determine the level of implementation. The study indicates that green procurement practices in Nigeria are implemented at a moderate level, with an overall mean score of 2.86 and an implementation rate of 57.2%. Waste reduction and management were the most engaged practices, followed by innovation and technology, and sourcing sustainable materials. However, adherence to strategies for implementing these practices is low, with weighted mean scores ranging from 2.30 to 2.47, an overall average of 2.39, and an mplementation rate of 47.82%. This indicates that while adoption exists, it has not yet been fully institutionalized. The study recommends
developing a robust system to track and report the implementation of green procurement across various sectors. The implication is that Nigeria is currently at an early to moderate stage of adoption, comparable to other developing economies. Stronger policy enforcement,
supplier incentives, institutional capacity-building, and coordinated stakeholder engagement are necessary to move toward international best practice.

Stochastic Noise Modelling of GNSS Time Series for Stability Assessment of Selected Permanent Stations in Nigeria

2026-08-03T11:58:46+00:00

Position time series from permanent Global Navigation Satellite System (GNSS) stations are
commonly used for estimating velocities of discrete points on the Earth's surface. An
understanding of background noise in the GNSS position time series is essential to obtain
realistic estimates of velocity uncertainties. This research analyses 6 years (2011 to 2016) of
daily GNSS time series from three Nigerian GNSS Reference Network (NIGNET) stations:
CGGN, FUTY, and CLBR, to characterise noise properties and evaluate their implications for
geodetic applications. The stations represent a latitudinal transect CGGN ~10°, FUTY ~09º,
CLBR ~04º across northern and southern Nigeria, providing valuable coverage in equatorial
and low-latitude environments. The datasets were modelled in Hector GNSS under three
stochastic noise processes with spectral index fixed to integer values: 0 for white, -1 for
Flicker, and -2 for Random walk. Model performance was assessed using Akaike Information
Criterion (AIC) and Bayesian Information Criterion (BIC), while noise amplitudes were
quantified for the East, North, and Up components. The results show that CGGN and FUTY
are consistently dominated by Flicker noise in their horizontal components, indicating the
presence of long-term correlated behaviour that affects velocity estimation. In contrast, CLBR
is better described by white noise in most components, suggesting more random and
uncorrelated variability at this coastal location. Across all stations, the Up component
exhibited the largest noise amplitudes, reflecting the greater sensitivity of vertical
measurements to atmospheric and ionospheric disturbances common in equatorial regions.
The Random walk model performed poorly at the three stations, producing high AIC/BIC
values and unrealistic velocity uncertainties, which confirms that it is not well-suited for these
datasets. Overall, the findings demonstrate that Noise characteristics in Nigerian GNSS
stations vary with Geographical location and environmental setting. Accounting for these
noise properties leads to more reliable velocity and deformation estimates and provides a
stronger foundation for improving the long-term stability and scientific value of the Nigerian
GNSS Network.

Evaluating the Procurement Processes and their Influence on Contract Performance at Kaduna Polytechnic

2026-08-03T12:08:39+00:00

This study aims to evaluate the procurement process and its influence on contract performanceat Kaduna Polytechnic. The specific objectives are to evaluate the procurement process at Kaduna Polytechnic, to identify factors affecting contract performance at Kaduna
Polytechnic, and to examine the influence of the procurement process on contract performance in Kaduna Polytechnic. This study utilized a survey as the source of primary data. Regression analysis was also used to describe the participants' demographic information. The researcher was able to identify the relationship between the procurement process and contract performance at Kaduna Polytechnic through regression analysis. The study population was 150, and 108 was chosen as the sample size using Krejcie and Morgan's table of 1970. The population comprised the Kaduna Polytechnic community, including academic and non-academic staff, contract managers, procurement officers, administration and finance departments, and the works department. Given the limited number of individuals or units in the population under study, the researcher chose to use a sampling method. Documentary sources, interviews, and questionnaires were used as tools for data collection. One hundred and eight (108) questionnaires were distributed to the respondents. Using SPSS and regression analysis, the findings show strengthened contract performance through quality project delivery, timely project delivery, cost control and budget, and a regulatory environment while focusing on sustainability and technology integration.

Systemic Challenges in Public Construction Procurement: A Mixed-methods Study of Consultants' Perspectives in Abuja, Nigeria

2026-08-03T12:16:03+00:00

This study investigates the challenges confronting consultants in the procurement of public construction projects within Nigeria’s Federal Capital Territory (FCT), situating these challenges within broader institutional and governance dynamics. A mixed-methods triangulation design was adopted to enhance methodological rigour and explanatory depth. Quantitative data were obtained through a structured questionnaire in which respondents assessed 52 potential challenges using a five-point Likert scale. In contrast, qualitative data were generated through semi-structured interviews to contextualise the institutional and behavioural factors underlying the quantitative findings. Sample size determination followed the Ayoub and McCuen (2000) formula for unknown populations, with a 95% confidence
level and a 5% margin of error. Quantitative data were analysed using mean score ranking, frequency distributions, and the Kruskal–Wallis test at a 0.05 significance level. Reliability testing produced a Cronbach’s alpha of 0.956. The findings revealed that the most severe
challenges were political interference in consultant selection, inflation, lack of transparency, procurement corruption, and poor material quality. The Kruskal–Wallis test showed no significant variation in perceptions among stakeholder groups (H = 5.805, df = 4, p = .214),
indicating that the challenges are systemic rather than role-specific. The findings highlight the need for stronger transparency measures, regulatory enforcement, and institutional capacity within Nigeria’s public procurement system. The study contributes to procurement
governance literature by demonstrating that consultant-related challenges are embedded within broader institutional, political, and regulatory weaknesses in public construction procurement.

Geospatial Analysis of Accessibility and Distribution of Public Secondary Schools in Jos North LGA, Plateau State, Nigeria

2026-08-03T12:43:37+00:00

This study examined the spatial distribution and accessibility of public secondary schools in Jos North Local Government Area (LGA), Nigeria, using Geographic Information Systems (GIS) and spatial analytical techniques. Data on school locations and population distribution were analysed using Population–School Ratio Analysis, Location Quotient (LQ), Buffer Analysis, and Nearest Neighbour Analysis (NNA). Findings revealed significant spatial inequalities in school distribution across the LGA. The overall population–school ratio was 21,800 persons per school, exceeding the recommended standard of one school per 10,000 population, with an estimated deficit of 29 schools. LQ analysis showed that Janta Adamu (2.62), Jos Jarawa (2.22), and Tafawa Balewa (1.94) were overserved, while Gangare (0.54) and Tudun Wada-Kabong (0.95) were underserved. Buffer analysis indicated that 84% of residential areas were located within 2 km of schools, while 2% were beyond 3 km. Nearest Neighbour Analysis produced a z-score of 1.2 and a p-value of 0.2, indicating a random
distribution pattern of schools. The study concludes that public secondary schools in Jos North LGA are unevenly distributed and recommends GIS-based educational planning and additional schools in underserved wards.

Effect of Locally Cultured Microorganisms on the Properties of Lateritic Concrete

2026-08-03T12:49:20+00:00

The rising scarcity, high cost, and environmental impacts of continuous river sand mining have necessitated the search for sustainable alternatives in concrete production. Lateritic soil, which is readily available, offers a low-cost and eco-friendly alternative. Accordingly, this
research investigated the properties of lateritic concrete produced with locally made microorganisms (LMOs) solution as partial water replacement. Experimental tests were conducted on aggregate properties, concrete workability, and the compressive and tensile strengths of concrete in line with BS EN standards. Results showed that the coarse and fine aggregates satisfied BS requirements, with a specific gravity of 2.72, bulk uncompacted density of 1,370, compacted density of 1,714 kg/m³, flakiness index of 13.16%, an elongation index of 12.97%, aggregate impact value of 10.82%, and an aggregate crushing value of 13.07%. Isolated microorganisms were cultured in various percentages, comprising Pseudomonas aeruginosa (25%), Staphylococcus aureus (5%), and Klebsiella spp. (10%), Escherichia coli (15%), Enterobacter aerogenes (15%), and Bacillus subtilis (30%) in a solution of approximately 10⁸ CFU/mL which complied with the requirements of BS EN ISO 4833-1:2013, BS ISO 21528-2:2017, and BS EN ISO 6888-1:2021. The solution demonstrated biomineralisation potential through carbonate precipitation, which enhances concrete durability. The control mixes showed good workability with slump values of 2.5 mm, 5 mm, 7 mm, 10 mm, and 13 mm for normal concrete without laterite, lateritic concrete made with 0% LMO, 2% LMO, 4% LMO, and 6% LMO, respectively. The compressive strengths at 28 days were 30.14 N/mm², 25.73 N/mm², 28.60 N/mm², 25.51 N/mm², and 24.82 N/mm² for normal concrete without laterite, 0%, 2%, 4% and 6% LMO water replacements, respectively. The study concludes lateritic concrete with 2% - 6% LMOs meets BS EN 12390-3:2019 specifications for nonstructural and selected structural applications. This work contributes to sustainable construction by validating lateritic soil and LMOs as viable ecofriendly materials.

Artificial Neural Network Approach to Predict the Water Absorption Behavior of Lateritic Concrete Containing Locally Made Microorganisms Solution

2026-08-03T12:57:34+00:00

The increasing scarcity, rising cost, and environmental impacts of continuous river sand mining have necessitated the search for sustainable alternatives in concrete production. Lateritic soil, which is abundantly available, presents a low-cost and eco-friendly substitute. Accordingly, this study investigated the effects of lateritic soil on concrete properties, with a locally made microorganism (LMO) solution used as a partial replacement for mixing water by weight of water. Experimental tests were conducted on aggregate properties, workability, strength, and water absorption. Microbial isolates such as Bacillus subtilis and Klebsiella sp. demonstrated biomineralisation potential through enhancement of strength and some durability properties through carbonate precipitation, leading to enhanced concrete water absorption. The 28-day compressive strengths were 30.14 N/mm², 25.51 N/mm², 28.60 2 N/mm² 25.57N/mm and 24.82 N/mm² for normal concrete without laterite, lateritic concrete made with 0% LMO, 2% LMO, 4% LMO, and 6% LMO, respectively. While water absorption increased with LMO inclusion, recording values of 3.11% for the control, 3.52%, 3.45%, 3.51% and 3.67% for 0% LMOs, 2% LMO, 4% LMO, and for 6% LMO, respectively. It indicates that the samples containing a low percentage of LMO in the lateritic concrete exhibit improved water absorption capacity, and all measured water absorption values fall within the acceptable range. To strengthen predictive analysis, a Conditional Tabular Generative Adversarial Network (CTGAN) was employed to expand the dataset to 500 records. An Artificial Neural Network (ANN) model developed with ten input features achieved excellent accuracy, with coefficients of determination (R²) of 0.9977 for training and 0.9967 for testing and very low mean squared error values (< 0.004), demonstrating strong precision and generalization capability. The study concludes that lateritic concrete incorporating up to 6% LMO has a compressive strength of 24.82 N/mm², and it can be applied where plain concrete is required. Furthermore, the integration of ANN with CTGAN-based data augmentation offers a robust computational framework for predicting water absorption. This research contributes to sustainable construction by validating lateritic soil and LMOs as viable, eco-friendly materials while advancing AI-driven concrete mix design tools.

Appraisal of Maintenance Management Systems in Public Tertiary Institutions in Yobe State, Nigeria

2026-08-03T13:02:47+00:00

This study appraises the effectiveness of Maintenance Management Systems (MMS) in public tertiary instit utions in Yobe State, Nigeria. It identifies critical factors constraining Planned Preventive Maintenance (PPM) and proposes evidence-based strategies for improvement. A quantitative research design was adopted, utilizing a structured questionnaire administered to 108 maintenance personnel (engineers, technicians, supervisors) across four selected institutions: Yobe State University, Federal University Gashua, Federal Polytechnic Damaturu, and Federal College of Education (Technical) Potiskum. Data from 98 valid responses were analyzed using descriptive statistics (mean, standard deviation) and inferential statistics (multiple regression analysis) via SPSS. The current MMS demonstrates moderate effectiveness (overall mean = 3.52). Key strengths include minimizing downtimeand improving operational efficiency. However, severe constraints exist: inadequate funding (mean = 3.72), high staff turnover (mean = 3.69), weak management commitment (mean = 3.82), and lack of Computerized Maintenance Management Systems (CMMS) (mean = 3.44). Regression analysis revealed that the four factors jointly explain 50.7% of the variance in MMS effectiveness (R² = 0.507, F = 21.93, p < .001), with funding constraints (β = 0.387, p < .001) and manpower capacity (β = 0.260, p = .008) having the strongest individual effects. The study recommends establishing dedicated maintenance budgets, implementing structured training programs, enforcing clear maintenance policies, and adopting digital tools like CMMS to transition from reactive to proactive maintenance.

Determinants of Construction Quality in Multi-Contractor Mass Housing Delivery: Evidence from the Malkohi Housing Project, Adamawa State, Nigeria

2026-08-03T13:19:58+00:00

The growing reliance on multiple contractors in mass housing delivery in Nigeria has
intensified challenges related to coordination, quality control, and timely project execution,
yet empirical evidence on performance drivers in such settings remains sparse, particularly in
Northern Nigeria. Thus, this study assessed construction performance in a multi-contractor
environment using the Malkohi Mass Housing Project in Yola, Adamawa State, as a case
study. A quantitative approach was adopted, with data collected from construction
professionals and analyzed using descriptive and inferential techniques. Performance
strategies with the highest aggregate mean score (3.59) emerged as the most influential factor,
followed by safety and workmanship with an aggregated mean = 3.58. The results indicate
that construction quality is significantly influenced by safety and workmanship practices (β =
0.298, p < 0.001), time efficiency (β = 0.276, p < 0.001), and performance strategies (β =
0.315, p < 0.001), with the model explaining 70.9% of the variance in construction quality (R²
= 0.709). These findings suggest that, beyond individual contractor capabilities, coordinated
planning, clear role definition, and structured management systems are critical to achieving
high-quality outcomes. The study demonstrates that improving multi-contractor performance
requires an integrated management approach that combines strategic coordination, effective
safety practices, and strict adherence to project schedules. The study recommends practical
guidance for project managers and policymakers to strengthen coordination frameworks,
enhance monitoring systems, and adopt performance-driven strategies to improve quality,
efficiency, and timely delivery of mass housing projects.

Assessment of Bird Diversity on Selected Waste Dump Sites in Awka, Anambra State, Nigeria

2026-08-03T13:22:46+00:00

Urban waste dump sites can provide supplementary resources for birds, yet their role in shaping avian community structure is poorly understood. This study assessed bird diversity across three selected waste dump sites: market, residential, and motor park areas. A total of 144 birds from six species were recorded, with Rock pigeons (Columba livia) being the most abundant. While overall bird abundance did not significantly differ between site types (F=5.1212, P=0.0504), species richness (S=6) did (F=7.0, P=0.027). Market dump sites exhibited the highest species richness (3.0±0.0), followed by residential (2.67±0.33) and motor park (2.0±0.0) sites. Diversity indices were highest at residential (0.8117±0.1232) and market (0.7028±0.0267) sites, with motor park sites showing the lowest (0.38466±0.0590).
Variance analyses confirmed significant differences in species richness (F=7.0, P=0.027), diversity (F=7.6254, P=0.0225), and evenness (F=5.4093, P=0.0454) across site types. Feeding guilds varied, with market sites showing a higher abundance of granivores and residential sites of omnivores and aerial insectivores. Terrestrial insectivores were only found at market sites. These findings highlight the role of waste dump sites as avian habitats, with variations in bird communities influenced by proximity to different human activities.

Physicochemical and Bacteriological Assessment of Water Quality in Gwafan Estate, Jos North, Nigeria

2026-08-03T13:26:09+00:00

Access to safe drinking water remains a pressing concern in many communities of the Jos Plateau, a region whose long history of tin and columbite mining poses a recognised risk of heavy-metal contamination. This study assessed water samples from three locations within the Gwafan estate, which were analysed for twelve physicochemical, heavy-metal, and microbiological parameters, and the results were benchmarked against the World Health Organisation (WHO) guidelines and the Nigerian Standard for Drinking Water Quality (NSDWQ). The water at all three sites was fresh and weakly mineralised, with total dissolved solids (27–46 mg/L), electrical conductivity (46–92 µS/cm), turbidity (0.2–3.6 NTU), nitrate (3.15–5.60 mg/L), and sulphate (3.44–5.45 mg/L) all comfortably within permissible limits, while cadmium was below the detection limit throughout. Two recurrent breaches were,however, identified. First, the pH at every location (6.10–6.20) fell below the lower bound of the 6.5–8.5 range recommended by both standards, indicating mildly acidic water. Second, lead exceeded the 0.01 mg/Lmaximum permissible limit at all three sites, ranging from 0.022 mg/L (Location 3) to 0.197 mg/L at Location 2, the latter representing roughly twenty times the allowable value. Location 2 also returned a positive Escherichia coli count (6 cfu/ml) and a high total coliform load (47 cfu/ml), with elevated phosphate (2.723 mg/L), indicating combined faecal and anthropogenic contamination; Location 3 likewise exceeded the coliform limit (60 cfu/ml). On the evidence presented, none of the three sources is fit for direct human consumption without prior treatment, with Location 1 the least impaired and Location 2 the most heavily contaminated.

Assessment of Off-campus Student Accommodation and Occupants' Satisfaction in Ilorin South Local Government Area, Nigeria

2026-08-04T06:55:10+00:00

This study assessed off-campus student accommodation and occupants' satisfaction as a panacea to housing challenges in Ilorin South Local Government Area, Kwara State, Nigeria, with particular focus on Akanbi Political Ward One. The study examined the socio-economic
characteristics of respondents, the nature and types of student accommodation available, the students' level of satisfaction with accommodation facilities, and problems faced by offcampus students. Data was collected from both primary and secondary sources. One hundred and seventy-four (174) structured questionnaires were administered to elicit information using random sampling techniques from students residing at the University of Ilorin offcampus. Descriptive statistical tools such as frequencies, counts, tables, and percentages were used for analysis. A Likert scale was also used to affirm the satisfaction level of students' accommodation facilities in the study area. Findings revealed that female students constituted a higher proportion (59.2%) than males (40.8%), while most Respondents were aged between 21 and 29 years. The majority were single (66.1%), although a considerable proportion were married (33.1%), indicating diverse housing needs. Most students earned between ₦31,000 and ₦60,000 monthly, from their parents as stipends, emphasizing affordability concerns. Students showed a strong preference for low-occupancy rooms, with 61.5% residing in rooms
with 1–2 occupants. The study further found that self-contained apartments and rooming houses dominate the accommodation types, while major challenges include high rent, poor infrastructure, insecurity, overcrowding, and inadequate basic services. Majority 50% of the respondents, were also not satisfied with hostel facilities due to incessant power failure, security situation, poor power and water supply, poor drainage systems, etc. The study concludes that improving off-campus housing through regulation, infrastructure provision,
and public-private partnerships can significantly alleviate student housing problems. Recommendations include policy intervention, rent control measures, and improved planning standards.

Influence of Soil-derived Bacillus Species on the Performance and Durability of Cement Mortar

2026-08-04T07:06:20+00:00

The use of bacteria in cementitious materials has emerged as an effective approach to enhance
self-healing and durability through microbial-induced calcium carbonate precipitation
(MICP). This study investigates the influence of two soil-derived bacterial species, Bacillus
subtilis and Bacillus mycoides, on the performance of cement mortar. The bacteria were
isolated from soil and demolished concrete environments in Samaru Zaria, cultured in nutrient
broth, and incorporated into mortar as a partial replacement (5% and 10%) of the mixing
water, along with calcium lactate and yeast extract. 50×50×50 mm mortar specimens were
prepared and tested for setting time, compressive strength, water absorption, ultrasonic pulse
velocity (UPV), and microstructural characteristics using scanning electron microscopy
(SEM). Specimens were cured for 7, 14, and 28 days. The Results showed that bacterial
incorporation improved mechanical and durability properties compared to the control. The
highest compressive strength was recorded in the 5% Bacillus subtilis (A5) sample, showing
up to 81% improvement at 28 days. Water absorption decreased significantly in bacteriatreated samples, indicating reduced porosity. SEM observations revealed denser
microstructures and the presence of crystalline deposits consistent with calcite precipitation,
particularly in Bacillus subtilis specimens. However, Bacillus mycoides showed
comparatively limited evidence of such precipitation under the conditions studied. The study
concludes that soil-derived Bacillus subtilis is more effective at enhancing the strength and
durability of cement mortar, with a 5% replacement identified as the optimum dosage.

Performance of Low-Alkali Rice Husk Ash–Periwinkle Shell Ash Geopolymer Composites Activated with Sodium Carbonate

2026-08-04T07:13:06+00:00

The construction industry is a major contributor to global carbon emissions due to its heavy reliance on Ordinary Portland
Cement (OPC), whose production is energy-intensive and environmentally unsustainable. Although geopolymer binders
have emerged as promising low-carbon alternatives, many existing geopolymer systems depend on highly concentrated
alkaline activators, such as sodium hydroxide, which are costly, hazardous, and associated with environmental concerns. In
addition, agricultural waste and marine waste materials like rice husk ash (RHA) and periwinkle shell ash (PSA) continue to
go untapped owing to their strong pozzolanic and cementitious behavior. Very few research studies have been conducted
using RHA and PSA together for geopolymer composites activation through low-alkali sodium carbonate–sodium silicate
blends. Consequently, there is insufficient knowledge regarding the mechanical, durability, and microstructural performance
of such sustainable binder systems, thereby limiting their adoption in practical construction applications. The development of
low-carbon cementitious binders for sustainable construction has intensified research into geopolymer systems produced
from agricultural and marine waste materials. In this study, rice husk ash (RHA) served as the primary silica-rich cementitious
precursor, while periwinkle shell ash (PSA) was incorporated as a calcium-bearing supplementary cementitious source
material, replacing RHA at levels ranging from 0% to 40% by mass of the total geopolymer binder. The RHA–PSA
geopolymer composites were activated using a low-alkali sodium carbonate–sodium silicate system and produced under
ambient curing conditions. The study focused on evaluating the effects of PSAincorporation on the mechanical and durability
performance of the geopolymer binder system. Particular emphasis was placed on compressive strength development at
curing ages up to 28 days, Rice husk ash (RHA) served as the primary silica-rich precursor, while periwinkle shell ash (PSA)
was incorporated as a calcium-bearing supplementary cementitious precursor at replacement levels of 0–40% by mass of the
total binder. The geopolymer composites were produced under ambient curing conditions, and their compressive strength,
water absorption, sulphate resistance, and microstructural characteristics were evaluated. Compressive strength was
determined at curing ages up to 28 days, while durability-related properties were assessed through water absorption and
sulphate resistance tests. Microstructural analysis was conducted to elucidate the geopolymerization products and gel
formation mechanisms. The results showed that the incorporation of PSA enhanced the strength and durability properties of
the geopolymer composites up to an optimum replacement level of 30% PSA, at which the highest compressive strength was
obtained. Further increases in PSA content beyond 30% resulted in a reduction in strength, which may be attributed to
excessive calcium content disrupting the geopolymerization process and promoting the formation of less stable reaction
products. The enhanced strength development at 30% PSA replacement was associated with the coexistence of sodium
aluminosilicate hydrate (N–A–S–H) and calcium aluminosilicate hydrate (C–A–S–H) gels, which contributed to matrix
densification and pore refinement. The water uptake was reduced while the sulphate resistance increased with increasing
curing time, showing that the concrete had become more resistant to water penetration and sulphate attack. Nonetheless, these
findings should only be regarded as indicative of an improvement in the resistance to the forms of deterioration studied. Given
that sodium carbonate activation may generate alkaline and carbonate species capable of influencing carbonation processes,
additional investigations involving carbonation resistance and reinforcement corrosion behaviour are required before
comprehensive durability claims can be established. Nevertheless, the findings demonstrate that RHA–PSA geopolymer
composites activated with a sodium carbonate–sodium silicate system possess favourable strength and selected durabilityrelated properties, making them promising low-carbon alternatives to conventional cementitious materials for applications
requiring ambient curing conditions.

Utilization of Ceramic Raw Materials from Birnin-gwari for the Production of High-temperature Ceramic Bodies

2026-08-04T07:25:04+00:00

The study investigated the utilization of ceramic raw materials sourced from Birnin Gwari
Local Government Area of Kaduna State, Nigeria, for the production of high-temperature
ceramic bodies. The research aimed to assess the suitability of locally available materials,
including clay, feldspar, and quartz, for industrial and studio applications in stoneware and
refractory ceramics. Samples collected from Sabon-Layi and Kungi were beneficiated and
analyzed for their physical and chemical properties in accordance with ASTM Designation C
373–88, with minor modifications to suit local laboratory conditions. The clay was
characterized through both physical tests and chemical analysis, revealing a high silica
content of 64.87%, alumina of 15.41%, and loss on ignition of 7.76%. The clay exhibited a
plasticity level suitable for forming, with a total shrinkage of 10% and a water absorption rate
of 11.1%. Triaxial and Quad-axial blending techniques were employed to formulate ceramic
bodies with varying proportions of clay, quartz, feldspar, and kaolin. The triaxial blend
achieved a shrinkage rate of 0.5% and an absorption rate of 9.06%, while the quad-axial blend
recorded a shrinkage rate of 0.6% and an absorption rate of 10.33%. Both blends were fired at
cone 9, exhibiting excellent vitrification and fusion characteristics at a gloss-firing
temperature of 1260°C. These findings confirm that the clay and associated raw materials
from Birnin Gwari are suitable for high-temperature ceramic applications, particularly in
stoneware and refractory production. The study recommends the use of Sabon-Layi clay as a
primary body material, while the feldspar and quartz can be optimized for glazes and
refractory compositions.

Corporate Real Estate Strategy Formulation and DecisionMaking Process in Kano Metropolis, Nigeria

2026-08-04T08:19:55+00:00

The paper aimed to investigate the corporate real estate strategy formulation and decisionmaking process in Kano metropolis, Nigeria. The study employed a quantitative research design, and data were collected through a questionnaire survey from 52 real estate professionals. The study adopted a convenience sampling technique, and SPSS software was used for data analysis. The study revealed that productivity, facilitating interaction, reducing cost, flexibility, and user satisfaction were ranked first to fifth and are found to be high
corporate real estate strategy formulation in the decision-making process. While promoting the brand and increasing real estate ranked at sixth to seventh, and found to be the least corporate real estate strategy formulation in the decision-making process in the study area.
Therefore, the study's findings conclude that cooperation is essential for successful real estate strategy formulation. By working together, stakeholders can develop and implement real estate strategies that are aligned with the needs of the company and its stakeholders, and that are more likely to be successful. The study recommended that the real estate companies should establish a stakeholder engagement committee, and this committee can be responsible for developing and implementing a stakeholder engagement plan. The study further recommended that the real estate companies should use technology to facilitate stakeholder engagement. There are several tools and platforms that can be used to communicate with stakeholders and gather feedback.

Project and Partner Contextual Factors Influencing Urban Public Housing Delivery Success in Kaduna Metropolis, Nigeria

2026-08-04T08:25:23+00:00

Urban public housing delivery in Nigeria is frequently characterised by cost overruns, delays, incomplete schemes, and governance challenges, suggesting weaknesses in how project conditions and inter-organisational relationships are assessed before and during
implementation. This study examines the influence of specific contextual factors on the success of urban public housing projects in Kaduna Metropolis, Nigeria. Grounded in contingency theory and project governance literature, the study focuses on two contextual dimensions: Project Context, comprising project duration, task complexity, task uncertainty, and task interdependencies; and Partner Context, comprising risk/reward structure, number of partners, collaboration history, and partner heterogeneity. A cross-sectional survey was administered once to built-environment professionals who had participated in public housing projects implemented between 2001 and 2022. Of the 261 returned questionnaires, 244 valid responses were analysed using Partial Least Squares Structural Equation modelling (PLSSEM). The results show that Project Context (beta = 0.483, p < 0.001) and Partner Context (beta = 0.312, p < 0.001) both have positive and significant effects on multidimensional project success, jointly explaining 58.7% of the variance. Project Context has the stronger relative influence, indicating that the technical and task environment of public housing schemes requires close governance attention. The study recommends that public housing agencies institutionalise contextual due diligence, adopt adaptive governance mechanisms, strengthen partner-selection processes, and build internal capacity for complexity and risk management.

Mediating Roles of Firms' Internal Factors on the Relationship between Mechanisation and Project Outcomes in Abuja, Nigeria

2026-08-04T08:41:38+00:00

Although mechanisation is widely recognised as a critical driver of construction performance,
the extent to which internal organisational factors influence this relationship remains
insufficiently explored, particularly in Nigeria. This study examines the mediating effects of
internal factors on the relationship between mechanisation and project outcomes in Nigeria. A
quantitative design was adopted, with data collected from 312 construction professionals
across 52 active building firms in Abuja. Data were analysed using PLS-SEM in SmartPLS,
with bootstrapping procedures employed to assess the significance of direct, indirect, and
mediating effects among the study constructs. Findings indicate that mechanisation has a
positive but modest direct effect on project performance (β = 0.18, p < 0.05), while the
inclusion of internal firms' factors significantly improves the model's explanatory power (R² =
0.318). Mediation analysis reveals that organisational management strategies (β = 0.052, p <
0.001) and operational and maintenance practices (β = 0.032, p < 0.01) exert significant
indirect effects, confirming partial mediation. In contrast, safety strategy factors did not show
a statistically significant mediating effect (p > 0.05), indicating their limited role in the
relationship. Thus, strong organisational and maintenance capabilities significantly enhance
the effectiveness of mechanisation in improving project outcomes. The study concludes that
strengthening internal management structures and operational systems is essential for
maximising the performance benefits of mechanisation in building construction projects.

The Management of Risks that Cause Variations in Construction Projects in Nigeria: A Fuzzy Approach

2026-08-04T08:59:44+00:00

The study is aimed at proposing the concept of Fuzzy Decision Variables as a basis for determining the conditions that give rise to design risk in construction for a selected client in Nigeria. A structured analysis technique is utilized in determining the Fuzzy Decision Variables that cause design risks. Fuzzy set analysis is used to estimate the magnitudes of the variables to obtain the total magnitude of the design risk. The variables of inadequate strategic briefing, inadequate concept briefing, inadequate detailed briefing, inadequate specialist consultants' designs, inadequate architectural services designs, and inadequate building designs were deduced to have caused the design with a significant increase in construction cost. Measures that could be taken to mitigate design risk include confirming architectural design at the strategic briefing stage, confirming design items at the concept briefing stage, confirming consultants' design before contract award, and confirming external works design. The concept of Fuzzy Decision Variables could be used to predict the occurrence of risk and its likely magnitude. It is recommended that the concept of Fuzzy Decision Variables could be utilized in developing Decision Support Systems to assist in risk identification and risk estimation.

Archaeometric and Geochemical Profiling of Bauchi Industrial Wastes for Sustainable Ceramics

2026-08-04T09:17:00+00:00

This study investigates the archaeometric, mineralogical, geochemical, and microstructuralbproperties of four ceramic raw materials obtained from Bauchi State, north-eastern Nigeria,bnamely waste glass (WG), granite dust (GD), marble dust (MD), and Sabon Gari clay (SGC).bThe research was undertaken to establish baseline compositional data for sustainable ceramicbproduction and future archaeological provenance studies. The materials were selectedbbecause they represent abundant industrial residues and locally available clay resources withbpotential for eco-industrial ceramic applications. Powder X-ray diffraction (XRD), X-raybfluorescence spectroscopy (XRF), and scanning electron microscopy coupled with energydispersive spectroscopy (SEM–EDS) were employed to determine mineral phases, oxidebcomposition, and microstructural characteristics. XRD analysis revealed that WG wasbpredominantly amorphous with minor quartz reflections, GD contained quartz and feldspathicbphases, MD was dominated by calcite and dolomite, while SGC exhibited kaolinite, illite, andbquartz phases. XRF results showed high SiO₂ contents in WG (64.92 wt. %), GD (47.81 wt.b%), and SGC (53.24 wt.%), indicating strong vitrification potential. MD contained high CaOb(59.56 wt.%), which contributes to fluxing and densification during firing. GD exhibitedbelevated Fe₂O₃ (19.05 wt.%) and K₂O (8.06 wt.%), which influence colour development and
liquid-phase formation. SEM observations showed angular fractured particles in WG,bcrystalline feldspathic grains in GD, Plate-like agglomerated clay particles in SGC, and finebcalcitic particles in marble dust. The complementary behaviour of the materials improved
vitrification and reduced firing temperature, demonstrating that Bauchi-derived industrialbresidues can serve as viable supplementary ceramic raw materials for sustainable ceramicbbodies while also providing archaeometric baseline data for future comparative studies on
pottery fabrics from north-eastern Nigeria.

Chemical Properties of Scrap Copper Modified with Calcium, Lithium, and Zinc Deoxidizers for Jewelry Production

2026-08-04T09:36:15+00:00

This study evaluated the effectiveness of calcium, lithium, and zinc as deoxidizers for improving the quality of scrap copper sourced from Muda Lawal and Makera in Bauchi Metropolis for jewellery production. A quantitative experimental research design was adopted, and scrap copper samples were selected using purposive sampling. Laboratory experiments were conducted to modify the scrap copper with calcium, lithium, and zinc deoxidizers and to determine their elemental compositions using metallurgical analysis. The results showed that the quality of the modified scrap copper depended on the type of deoxidizer used. Lithium-modified samples contained high iron content (up to 8 wt.%) and lower concentrations of alloying elements such as tin, aluminium, and silicon, reducing their suitability for jewellery production. In contrast, samples deoxidized with calcium and zinc at a copper-to-deoxidizer ratio of 5:1 exhibited lower iron content and favourable concentrations of manganese, aluminium, silicon, and zinc, indicating improved suitability for jewellery applications. The study concludes that calcium and zinc are more effective deoxidizers than lithium for enhancing the quality of scrap copper intended for jewellery production. Further studies are recommended to evaluate the mechanical and physical properties of the modified alloys, including hardness, colour, corrosion resistance, strength, and electrical conductivity.

Mechanical Performance of Sustainable Concrete Incorporating Periwinkle Shell Ash and Locally Sourced Nano-Titanium Oxide

2026-08-04T09:40:20+00:00

This study investigates the mechanical performance, setting characteristics, and workability of sustainable concrete incorporating periwinkle shell ash (PSA) as a partial replacement for ordinary Portland cement and locally sourced nano-titanium dioxide (LSTiO₂) as a
nanomodifying additive. Concrete mixtures containing 5–17.07% PSA and 1.17–6.83% LSTiO₂ by weight were produced and evaluated for density, compressive strength, flexural strength, splitting tensile strength, and setting time behaviour. Results showed that all mixes remained within the normal-weight concrete range, with densities between 2338 and 2382 kg/m³. PSA incorporation increased the initial and final setting times due to its slower pozzolanic reactivity, while moderate LSTiO₂ contents enhanced hydration and reduced the
delay in setting. Initial and final setting times ranged from 110–150 min and 200–250 min, respectively, satisfying ASTM C191 and BS EN 196-3 requirements and indicating acceptable workability for construction applications. Although higher PSA contents reduced early-age compressive strength, the synergistic incorporation of LSTiO₂ improved hydration and strength development. At 28 days, compressive strength ranged from 17.66 to 27.97 MPa, with several PSA–LSTiO₂ mixtures attaining strengths comparable to or exceeding the control concrete. Enhanced flexural and splitting tensile strengths further indicated improved crack resistance and matrix densification. The findings demonstrate that PSA and locally sourced nano-TiO₂ can be effectively combined to produce structurally viable, workable, and
environmentally sustainable concrete with enhanced mechanical performance.

Thermal Cycling and Compatibility Analysis of Selected Organic Phase Change Materials (PCMs) for Thermal Energy Storage in Solar Cookers

2026-08-04T09:56:22+00:00

In homes, cooking uses a significant amount of energy. Cooking requires more than 30% of the energy used in many underdeveloped countries. Solar cookers (SCs) have been viewed as a potential remedy for the worldwide issue of fossil fuel dependence, which has led to a number of environmental difficulties. But the intermittency of solar radiation means that cooking will not be feasible during the evening times. Latent heat thermal energy storage (TES) systems offer a solution to extending the use of solar cookers in the evening but there is the need to find suitable phase change materials (PCMs) that can satisfy storage requirements. This work screened suitable organic PCMs and studied their suitability for application in TES between 100^o and 200^oC. It was discovered that the melting temperatures of five PCMs fell within this range, making them suitable for solar cooking. These materials underwent preliminary preselection based on economic factors, storage potential, and health risks. This resulted in selecting four organic materials (acetanilide, adipic acid, D-mannitol, and High-Density Polyethylene (HDPE)) that satisfied the initial selection criteria. These materials were then
examined and described for thermophysical characteristics, cycling stability, and compatibility with storage confinement (namely stainless steel and aluminum). DSC was used to investigate changes in melting temperature and latent heat, whilst FTIR was utilized to
investigate the chemical stability of the PCMs over numerous thermal cycles. In HDPE a new -1 functional group C-O was observed at 1171 cm stretching indicating oxidation and over 30% lost in latent heat was recorded after several cycles. Similarly, new stretching at wavelength -1 1100-1250 cm were observed in D-mannitol and lost 100% of its energy storage capacity after 100 cycles. Acetanilide and Adipic acid showed good compatibility with aluminum as storage container after undergoing 100 thermal cycles making them suitable materials for TES application in solar cookers.

Cooling Tropical Cities: Evaluating Landscape-Driven Urban Heat Island Mitigation Across Multi-Regional Case Studies

2026-08-04T10:27:25+00:00

Urban heat is becoming severe in fast growing tropical cities, where dense development, low vegetation cover, and extensive impervious surfaces elevate thermal stress. This study compares landscape-led mitigation across Lagos, Jakarta, Medellín, and Chennai by reviewing 34 eligible studies under PRISMA guidance. A comparative matrix and a Landscape Cooling Performance Index (LCPI) were used to assess performance, showing that vegetative and blue-green systems commonly reduce temperatures by about 1.5°C to 4.5°C, with results shaped by spatial continuity, project scale, and governance capacity (Yilmaz et al., 2025). Medellín's corridor-based greening shows the strongest cooling effect, whereas the more fragmented approaches in Lagos and Chennai deliver moderate results. The study contributes both a conceptual frame for evaluating landscape cooling and practical lessons for climate-responsive design in tropical cities.