Land-use and land-cover dynamics nexus to local climate variability in Suha watershed, upper Blue Nile basin, Northwest Ethiopia

This study examined the nexus between land use, land cover dynamics, and climate variability and change in the Suha sub-watershed of the upper Blue Nile basin (1990-2020). Data sources such as Landsat images (LULC, NDVI, and LST) and NMAE/KNMI (rainfall) were used and analyzed using ArcGIS 10.7.1, QGIS 2.8.3, and XLSTAT 19. The relationship between NDVI and climate variables was determined using Pearson's correlation coefficient, while the cellular automata-artificial neural network technique was used to predict future LULC change. Results showed that among the six land use classes, cultivated land gained more than 30%, while grassland lost more than 20% in each decade. The LULC dynamic in the future also showed that bare land and the built-up area had the highest increments, while bush-shrub land had the highest diminishing trends. The NDVI values of each land use class were between -0.14 and +0.74 in 1990 and -0.09 and 0.68 in 2000, respectively. In 2013, the NDVI value ranged from -0.04 to +0.46, and in 2020, it was from -0.08 to 0.55, respectively. The NDVI value of the different land uses showed a decreasing trend. However, LST and rainfall in the watershed showed an increasing and decreasing trend, respectively, which is associated with the LULC daynamics. The correlation between NDVI and LST was found to be negative, whereas the relationship between NDVI and rainfall was positive. Hence, an appropriate use of land is an undeniable fact to minimize the undesirable influence of LULC change on climate variability in the area.