A spatio-temporal analysis of the water–energy–food–environment nexus in Iran using a spatial econometric approach

Given Iran's location in a dry region and the serious challenges it faces regarding resource security, understanding the complex interactions between these four domains is essential for achieving sustainable development. Hence, this study analyzes the water-energy-food-environment (WEFE) nexus in the provinces of Iran over 20 years (2001-2021). This study employs an innovative framework that integrates the environmental component, developing a comprehensive assessment index based on the degree of harmony model. It also examines the spatial-temporal patterns and factors affecting the convergence of this nexus using spatial econometric models. The findings of Moran's test confirm the presence of strong positive spatial autocorrelation, indicating the formation of homogeneous clusters of provinces with similar levels. Furthermore, a finding of conditional spatial β convergence indicates a gradual reduction in the gap between provinces in the long term. The results demonstrate that factors such as economic development, area size, population, and public budget expenditures significantly affect the convergence of the water-energy-food-environment nexus. This study emphasizes the need to transition from fragmented management toward "integrated and networked resource governance" and its findings could provide a framework for policymaking for sustainable development in Iran and similar countries.