The study offered the opportunity for an evaluation of the role of Remote Sensing and Geospatial techniques in flood disaster risk management and development of spatial decision support system for flood risk assessment and management in Abeokuta metropolis. Datasets used includes cloud free high resolution satellite images and Shuttle Radar Topographic Mission (SRTM) data downloaded from earth explorer site. Soil data used was obtained from Food and Agriculture Organization (FAO’s) Harmonised World Soil Database, while rainfall data was obtained from the Climate Hazards Group InfraRed Precipitation Station. Maps of flood enhancing factors namely: soil types, rainfall intensity, drainage density and topography were created in Geographic Information Systems using same scale of 1: 50,000 and Geographic coordinate system (WGS 1984). All maps were produced in raster format with the same cell grid cell size of 0.0028 mm. They were then subjected to weighting by ranking and Multi-Criteria Analysis (MCA) using the Weighted Linear Combination. The study identified topography and land use as key factors contributing to flooding within Abeokuta metropolis. Obstruction of natural drainage channels by buildings aggravates disasters from flash flood events.

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Metals contamination in shallow wells through solid waste leaching is a serious environmental problem with potential contribution to the global cancer cases. This paper evaluated the health risks of metals in shallow wells around dumpsites in Abeokuta Metropolis, Nigeria. Five dumpsites were purposively selected to sample twenty-five shallow wells. In-situ and laboratory analysis for pH and Electrical conductivity, copper, lead, Cadmium, Iron, and Chromium were conducted following the APHA standard procedure. Carcinogenic and non-carcinogenic risks for oral and dermal routes were evaluated for adult male and female, children, and infant. Findings show that all wells are highly acidic (pH = 4.08–5.24), with Fe and Cd concentration above the established limits. Wells around Obada, Obantoko, and Saje dumpsites have high EC (upto 1200µS/cm), Cu, and Pb concentration above the permissible limits. Non-carcinogenic risks for oral ingestion were significant (HI > 1) for all age groups, and the significance level across dumping area increases in the order: Saje > Obantoko > Obada > Idi-aba > Lafenwa. All wells assessed in Saje and Obantoko recorded significant HI of dermal exposure for children and infants. Cancer risks were significant (CR > 1.0E-04) for all age groups, and metal contributions followed: Cd > Cr > Pb. Overall trend of significant risks for non-carcinogenic and carcinogenic via oral and dermal routes are in the order: infant > children > adult female > adult male. This show that groundwater users within the studied areas may experience diverse illnesses or cancer in their lifetime, particularly children and infant.

The study investigated the spatial variability in the distribution of noise pollution in Federal University of Agriculture, Abeokuta. Measurements of noise were taken from 10 locations on campus namely; the academic environment including the University library and college lecture auditoria, the residential areas comprising the Student hostels and Vice-chancellor’s lodge as well as other populated areas like the car park and student union building. The noise measurement was done in the morning and evenings of Mondays, Wednesdays and Saturdays over a period of 3 weeks in July 2019. The noise measurement was done with the aid of Smart Sensor Digital Sound Level meter (Model: AR824). The sampling points were geo-located using a hand-held receiver for Global Positioning Systems (GPS). Questionnaires were administered to members of the University community (staff and students) to determine their respective perception of campus noise on academic activities. Data (noise and survey) were subjected to statistical analysis. Spatial analysis of the noise levels includes surface interpolation (Krigging) to determine the spatial pattern of noise across the campus, particularly, the most tranquil and most chaotic locations. The results show noise pollution levels reaching 74.3 (db) and 73.0 (db) during weekdays at some locations on campus. The noise emission level at some locations within the University exceeded the World Health Organization and Federal Ministry of Environment of Nigeria’s permissible level of 55 db for residential areas. Generally, it was observed that the ambient noise from heavy duty generating with the student chattering put noise level above 35(db) to 55(db) recommended for educational institutions. It can be inferred from statistical analyses and spatial interpolations of recorded noise levels, that noise levels of many areas in FUNAAB exceed the recommended 40 db required for an institution of higher learning. The study however finds that staff and students have adjusted to the noise on campus. Lecturers have resorted to the use of public address systems in large classes while students go to serene locations for better assimilation when studying. The study recommends reduction of point-source noises such as replacing the diesel generators with solar power. Signage should be displayed at sensitive areas such as library to reduce unnecessary noise.

The paper employed Remote sensing data in a multi-decadal assessment of vegetal to urban land cover transition along Lagos-Ibadan expressway. The forty-year assessment commenced in 1980 and ended in 2020. Landsat imageries acquired for the respective periods were subjected to supervised classification. Results reveal massive conversion of vegetated areas into built-up areas. The transition became pronounced from the second decade with 30,226 and cumulative of 48,455 Hectares of vegetation transforming into built-up area. During the third decade (2000 to 2010), additional 44,780 and cumulative of 93,235 Hectares of green area was converted into built-up areas. The largest transition was recorded in the last decade (2010 to 2020) during which vegetated area covering 50,827 Hectares was converted to living or industrial areas giving a cumulative transition of 141,065 in year 2020 Pearson moment correlation showed a high negative correlation with a coefficient value of -0.86. Hectares of vegetal areas into built-up or bare surfaces.