The impact of digital infrastructure on industrial ecology: Evidence from broadband China strategy

The coordination of economic development and ecological conservation has emerged as a global trend for sustainable development. This paper utilizes the "Broadband China" policy as a quasi-natural experiment, employing panel data from 279 prefecture-level cities spanning from 2006 to 2019. By constructing a spatial difference-in-differences (SDID) model, it examines the impact of digital infrastructure (DI) on industrial ecology (IE). The study finds that DI enhances both local and neighboring IE, with a spatial attenuation boundary of 600 km for IE impacts on neighboring cities. DI primarily facilitates the transformation of IE by promoting green technology innovation and expediting factor mobility. Heterogeneity analysis conducted using a spatial difference-in-difference-in-differences (SDDD) model reveals that DI has a greater impact on IE in resource-based cities, highly marketized regions, small-scale cities, and eastern regions. This research provides a novel perspective for exploring the transformation of IE theoretically and offers practical insights for leveraging digitization to promote IE.