Synergistic optimization and interaction evaluation of water-energy-food-ecology nexus under uncertainty from the perspective of urban agglomeration

Abstract

Faced with resource scarcity and accelerated urbanization, the synergistic optimization of water, energy, and food resources is crucial for urban agglomeration. This study focuses on the Chengdu-Chongqing Economic Circle (CCEC) with the aim of achieving the following three specific objectives: (1) constructing a synergistic optimization model for the Water-Energy-Food-Ecology Nexus (WEFEN) in urban agglomeration; (2) developing the Basic Trade-off Solution (BTS) to enhance social, economic, and ecological benefits; and (3) analyzing the impact of different factors within the water, energy, and food systems on the spatial distribution of ecological footprints and their interactions. To achieve these objectives, this study innovatively integrates water footprint theory, robust coefficients, multi-strategy meta-heuristic optimization algorithms, and compromise programming (CP) techniques, significantly improving the model's ability to allocate water and land resources under uncertainty. Furthermore, the Optimal Parameters-Based Geographic Detector (OPGD) is introduced, revealing that electricity consumption is the primary driver of the spatial distribution of ecological footprints. It is also found that the orthogonal interaction between food and energy system factors significantly amplifies the spatial response of ecological footprints. The results demonstrate that the proposed BTS, under the dual uncertainty of surface water supply and economic loss risks, can enhance social benefits, improve the economic efficiency of irrigation water, and reduce ecological footprints. This study provides a solution for optimizing water and land resource patterns under the trade-offs between social, economic, and environmental relations, supporting the achievement of SDG 11.a for the sustainable development of urban agglomeration.