Understanding the Impact of Land Use and Land Cover Change on Water-Energy-Food Nexus in the Gidabo Watershed, East African Rift Valley

摘要

Land use and land cover (LULC) changes have significant influences on the water-energy-food (WEF) nexus, as the WEF nexus characteristics change naturally due to dynamic LULC changes. However, understanding the WEF nexus' potential and characteristics in the watershed under the influence of LULC changes is less commonly explored. This study used the social network analysis (SNA) model to analyze the interaction between land use (LU) types and water, energy, and food nexus attributes. Moreover, we used regression analysis to analyze the impact of various LU types on the WEF nexus. The LULC maps of 1986, 2000, 2011, and 2019 were prepared by digital classification method with proper accuracy using satellite imagery. The results show that agroforestry is the dominant LU type, accounting for 25.8-53.1% from 1986 to 2019. Further, settlement increased a 100-fold, which shows the dynamic LULC changes. SNA computed the maximum inter-linkage for forest and water access attributes, while agroforestry and food attributes acted as bridge in the network. This shows that there was inter-dependence between LULC changes and the WEF nexus. This result suggests that LU dynamics can exert pressure on the WEF nexus' resource potential, resulting in WEF insecurity. The analysis of impacts of LULC changes on the WEF nexus shows that the changes that occurred in major LUs (i.e., agroforestry, bare land, settlements, and grass land) had significantly impacted hydrological behaviors, energy characteristics, and food production potential. Understanding LULC changes helps us to conserve and manage WEF nexus resources and to resolve the current dilemmas between land, water, energy, and food sector policies and decisions to improve resource productivity, lower environmental pressure, and enhance human wellbeing and security.