The impact of water resource constraints on the industrial linkage of the three major economic circles in Shandong Province

Shandong Province's water resource constraint is nearing its upper limit, posing the greatest obstacle to the integrated development of Shandong's three major economic zones. To promote coordinated regional resource and economic development and facilitate industrial synergy and integrated growth across the three economic zones, this paper constructs a comprehensive water resource constraint evaluation system based on panel data from 2006 to 2022 across Shandong's prefecture-level cities. The evaluation system integrates three criteria: resource ceilings, efficiency floors, and ecological thresholds. Employing a two-way fixed effects model and a mediating effect model, this paper empirically examines the impact mechanisms of water resource constraints on the industrial linkage from the novel perspective of water resource constraints. The results indicate that water resource constraints generally limit the industrial linkage of Shandong's three major economic zones, with this finding remaining valid after endogeneity and robustness tests. Mechanism analysis reveals that water resource constraints promote industrial linkage by facilitating virtual water trade across the three major economic zones and the Southern Shandong Economic Zone while suppressing such trade in the Jiaodong Economic Zone; They enhance green technological innovation to foster industrial linkage among the three economic zones; They optimize industrial structures to elevate industrial linkage across the three major economic zones, the Provincial Capital Economic Zone, and the Southern Shandong Economic Zone.