【摘要】 数字化浪潮下，政府门户网站成为政府数字化战略的核心支点，而政务社交媒体是政府门户网站重要的拓展渠道，两者代表和反映着现代政府与数字技术融合的深度和进程。基于全国各城市的政府网站工作年度报表数据，实证检验政务社交媒体对于政府门户网站访问量和公众参与度的具体影响及其背后机制。研究发现，政务社交媒体对网站访问量和公众参与程度的影响兼具“引流”效应和“替代”效应，呈现出先促进后抑制的“倒U形”趋势；这种复合效应在不同地区间、不同社交媒体类型间表现出一定程度的差异性。同时，政府行政效率和政策信息的传播覆盖度对这种复合效应起到了不同程度的调节作用。更多还原

【Abstract】 Amid the digital wave, government portals have become a central pillar of state digitalization strategies, while government social media platforms serve as key extensions of these portals. Together, they reflect both the depth and pace of integration between modern governments and digital technologies. Drawing on annual government website reports from cities across China, this study empirically examines the specific effects of government social media on portal traffic and public engagement, as well as the mechanisms behind these effects. The results reveal a dual influence: government social media exerts both an“attraction effect”—driving users to official portals—and a“substitution effect”—diverting attention away from them. These opposing forces form an inverted U-shaped relationship, where social media initially promotes but eventually inhibits both website visits and civic participation. This composite effect varies across regions and types of platforms. Furthermore, administrative efficiency and the breadth of policy information dissemination moderate the strength and direction of these effects to varying degrees.更多还原