The effects of source credibility and content objectivity on pro-environmental post engagement on social media: A case study of Chinese TikTok (Douyin)

Social media has become a primary channel for disseminating environmental information aimed at raising pro-environmental awareness. Post engagement plays a crucial role in effective information dissemination; therefore, environmentalists, government organizations and environmental protection agencies are increasingly focusing on enhancing pro-environmental post engagement on social media. This study applies the heuristic-systematic model to examine the effects of source credibility—a heuristic cue—and content objectivity—a systematic cue—on pro-environmental post engagement. Using 700 short videos from the Chinese TikTok (Douyin) platform, we empirically tested the proposed model. The results show that source credibility positively influences pro-environmental post engagement, whereas content objectivity negatively impacts pro-environmental post engagement, with a more significant effect than source credibility. Furthermore, this study reveals that content objectivity weakens the relationship between source credibility and pro-environmental post engagement. These findings provide empirical support for the attenuation effect in the heuristic-systematic model, demonstrating that when heuristic and systematic cues exert opposing influences on post engagement, systematic processing inhibits heuristic processing.