GEOSPATIAL ASSESSMENT OF LAND SURFACE TEMPERATURE IN OWO FOREST RESERVE AREA, ONDO STATE NIGERIA

Abstract

Nigeria’s forest reserves no matter where they are located act as the last succour for the entire citizenry by rendering ubiquitous services that significantly contribute to her economy. This study was intended at assessing the Land Surface Temperature (LST) in Owo Forest Reserve Area (FRA) with a view to sustainable forest management. The essential objectives set for the research include: (i.) assessing the vegetation changes in Owo Forest Reserve Area (ii.) evaluating the LST in Owo forest reserve and (iii.) relating changes in vegetation cover to LST in other to ascertain whether the observed difference in vegetation cover has significant effect and contribution either positively or otherwise to LST values obtained in Owo forest reserve. Recorded spatial coordinates of some selected points constitute the primary data while the secondary data were the satellite dataset, which includes: the Operational Landsat Imager, Enhanced Thematic Mapper, and Thematic Mapper of different years (1991, 2002, 2014, and 2020) used for mapping the vegetation change in the forest reserves. Specifically, thermal bands of the Landsat image in conjunction with the Normalized Difference Vegetation Index (NDVI) were utilized for mapping the LST which is the hallmark of the research. Various data acquired were processed according to the best practices. The results obtained showed that moderate vegetation (shrubs and scattered trees) has been increasing, which signifies that these categories of vegetation in Owo forest reserve area is not depleting for the whole period of study. It was also discovered from the results garnered from 1991 to 2020 that areas with vegetation (Dense, moderate, and sparse) had the least LST values while the forecast probable future LST values for the year 2030 are in the purview of 24.22°C(minimum) and 53.98°C (maximum) which may have negative implications on the forest reserve. The research recommends a significant increase in the rate of tree planting and preserving green areas (vegetation) in order to mitigate the upsurge of LST while laws guiding illegal logging should be upheld with the utmost tenacity.

Keywords

• Land Surface Temperature
• Normalized Difference Vegetation Index
• Spatial
• Landsat Imagery
• Single Window (SW) algorithm