Past and future land use/land cover, and climate change impacts on environmental sustainability in Vea catchment, Ghana

LULC and climate change are the two most common manifestations of global environmental change. The objective of this study was to quantify past and future LULC and climate change impacts on environmental sustainability in the Vea catchment of Ghana. The past LULC change (1998-2022) was analyzed using ERDAS Imagine 15 upon the application of the Support Vector Machine (SVM) classifier algorithm. The CA-Markov was used to predict land-use changes in 2038 and 2054. Climate change was projected under SSP 4.5 and SSP 8.5 emission scenarios using the R software. The projections from an ensemble mean of SSPs in the near future (2023-2052) and far future (2071-2100) were compared to the reference period (1993-2022). The results show that, between 1998 and 2022, cropland increased from 10.9% to 51.98%, while grassland and forest areas decreased from 54.8-18.14% and 31.7-22.73%, respectively. The results of the predicted LULC change showed an increase in cropland from 181 km2 in 2038 to 183 km2 in 2054 at the expense of grassland and forest, which are expected to decrease from 51-50 km2 and 73-71 km2, respectively. The findings of climate change show the projected increases in average temperature range from 2.10 to 3.5 degrees C under SSP4.5 and from 2.7 to 4.15 degrees C under SSP8.5. Under the SSP4.5, annual average precipitation is anticipated to decrease by 12.34-13.1%, while the SSP8.5 projects a decrease of 12.6-13.6%. Results will help in the setting up of long-term environmental management strategies in the catchment as well as the development of appropriate adaptation methods to mitigate the ongoing impacts of LULC and climate change on environmental sustainability.