## 2 Theoretical Analysis and Model Development  
Regional green technological innovation (RGTI), known for its ability to reduce energy consumption, minimize pollutant emissions, improve environmental quality, and foster green economic development [25], is widely recognized as an effective pathway to address the high carbon emissions of the construction industry [23]. Existing studies have explored RGTI from various perspectives and methodologies, yielding a wealth of findings [7], which can be categorized into direct effects and indirect impacts. In terms of direct effects, RGTI can reduce energy consumption and carbon emissions intensity by promoting the adoption of low-carbon technologies and driving organizational transformation in enterprises, thereby reshaping traditional high-carbon production models. For instance, [PERSON] et al. (2020) examined patent data to analyze the direct effects of seven types of green technologies on reducing carbon intensity at the industry level [26]. They found that the vertical spillover effects of green technologies significantly enhanced reductions in carbon intensity. In the power sector, low-carbon technologies such as carbon capture and storage, alternative fuel power generation, and smart grids have substantially reduced carbon emissions [27]. The construction industry is no exception. Furthermore, RGTI may indirectly contribute to carbon reduction by enhancing resource utilization efficiency. As a typical resource-intensive industry, the carbon emissions of the construction sector primarily stem from high-intensity and low-efficiency resource use. Studies have shown that implementing green and low-carbon technologies in the cement industry can significantly reduce carbon emissions [28]. Additionally, green building practices, building-integrated photovoltaics (BIPV), and carbon-negative technologies are widely regarded as critical pathways to reducing the lifecycle carbon emissions of the construction industry [29]. By promoting green technologies in areas such as optimized building design, intelligent construction management, and resource recycling, the construction sector can effectively reduce its dependence on fossil fuels [30] and establish a more environmentally sustainable resource utilization model. However, regional disparities in socioeconomic development levels can significantly influence the effectiveness of implementing RGTI. Economically developed regions, benefiting from robust financial resources, technical foundations, and policy support, demonstrate broader applications of green technological innovation outcomes [31]. In contrast, economically underdeveloped areas often face challenges such as limited technological diffusion capabilities, resulting in lower technology adaptability and transformation efficiency. More importantly, disparities in resource endowments and imbalances in industrial structures further exacerbate the technological gap in emissions reduction within the construction sector across regions [32]. Although previous studies have deeply examined the direct role of RGTI in the low-carbon transition of the construction industry, its carbon reduction effects are often constrained and influenced by more complex productivity systems. Particularly in the context of a rapidly growing digital economy, the coupled relationship between the carbon reduction effects of green technological innovation and productivity quality transformation has become increasingly prominent. In recent years, with the progressive deepening of research on the effects of green technological innovation, the focus has gradually expanded from single-dimension technological innovation to a quality-oriented productivity development paradigm. The concept of new quality productivity (NQP) has provided an innovative theoretical framework for advancing the study of green technological innovation's role in carbon reduction [33].