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The replacement of natural surfaces with synthetic materials that aggravate the environment is synonymous to urban spaces. Therefore, the objective of this paper is to evaluate the impact of land use and land cover on the land surface temperature (LST) of Oluyole Local Government Area in Ibadan, Nigeria using Landsat satellite images over a 20-year period (2000-2019). Data obtained were classified using the Maximum Likelihood algorithm supervised classification to create the Land-use Land cover (LULC) maps. Thereafter, the Land Surface Temperature (LST) was retrieved using the single-chan­nel method. The study area experienced shifts in land cover classes, including an increase in grassland (27.35%) and built-up (17.88%) areas, and a marginal decline in forest cover (1.91%). These changes corresponded to temperature variations, with an observed increase in LST of both minimum and maximum values (4.22oC and 4.01oC) between year 2000 and 2019 respectively. Forest conservation and sustainable land use practices are recommended to mitigate adverse climate effects associated with urban sprawl and land cover and land use change. This research contributes valuable insights for policymakers and urban planners aiming to balance development with environmental conservation and climate resilience.

Evapotranspiration's impact on crop production, determined by water consumption in plants, varies across locations due to surface and climate differences. Traditional ground-based methods for measurement fall short in capturing these variations. In order to address this, the study evaluated and mapped the evapotranspiration in the forest-savanna transition zone of Ogun State, South-western Nigeria using a geo-informatics approach. Over six years, 12 Landsat images were collected, representing dry and wet seasons. These images were used to estimate the Normalized Difference Vegetative Index (NDVI), indicating vegetation density, and compute evapotranspiration values across the area. During the dry season, NDVI ranged from -0.326 to 0.376, and during the wet season, it ranged from -0.435 to 0.780, showing higher vegetation cover in the wet season. Evapotranspiration values varied across different regions. In Abeokuta South, Abeokuta North, and Odeda Local Government Areas, values ranged from 2.83 to 6.37 mm/day, 0.12 to 2.64 mm/day, and 3.12 to 5.44 mm/day, respectively, influenced by varying vegetation characteristics. The geo-informatics approach offered a realistic representation and spatial understanding of evapotranspiration, proving cost-effective and accessible. In conclusion, the study recommends the geo-informatics approach for evapotranspiration measurement due to its ability to consider spatial characteristics. This understanding is essential for effective water resource management and crop planning in the Forest-Savanna transition zone of Nigeria.

The study assessed the vegetation of Ilaro Forest Reserve through remote sensing approach for years, 2015, 2019 and 2022. Satellite images of the corresponding years were downloaded and analyzed to compute the Normalized Difference Vegetative Index (NDVI) and to produce an NDVI map. The result showed that in 2015, there were four land covers which are; Builtup Areas, Shrubs and Grasslands, Sparse vegetation and Dense Vegetation while in 2019 and 2023, five land covers were observed which include Builtup Areas, Shrubs and Grasslands, Sparse vegetation, Dense vegetation and Barren Land. Furthermore, each of the land covers varied from 2015 through 2022. There was increase in barren land (0.01%), dense vegetation (0.72%) and sparse vegetation (5.35%) while builtup areas and shrubs and grasslands decreased by 0.08% and 5.99% respectively between 2015 and 2019. However, from 2019 to 2022, shrubs and grasslands decreased further by 3.66% while barren land, built-up areas, dense vegetation, and sparse vegetation increased by 0.02%, 0.06%, 0.03% and 3.53% respectively. The overall coverage of the land showed that from 2015 to 2022, there was a general increase in barren land (0.03%), dense vegetation (0.75%) and sparse vegetation (9.12%) while a decline in built-up areas (0.02%) and shrubs and grasslands were observed. The study showed that there was vegetation gain in the forest reserve due to reforestation project sponsored by the State government in 2017. The project impacted positively on the forest reserve and more of these projects should be encouraged by government. [ABSTRACT FROM AUTHOR]