Exploring the Relative Importance and Nonlinear Associations of Waterfront Recreation Spaces with Residents’ Physical Health: Evidence from Changchun, China

The relationship between urban waterfront spaces and health is widely recognized. However, the relative importance and nonlinear associations of specific attributes with residents’ physical health remain unclear. Drawing on survey data from 375 users across seven waterfront parks in Changchun, this study uses a Gradient Boosting Decision Tree model to examine how 37 perceived attributes of waterfront recreation spaces contribute to self-assessments of physical health, focusing on their relative contributions and nonlinear associations. The aim is to provide exploratory evidence for the empirical accumulation of the relationship between waterfront spaces and health. The results show that waterfront walkways and plaza lighting had high relative importance in the prediction model, at 8.8% and 8.2%, respectively. These findings suggest that spatial connectivity and around-the-clock accessibility may play a fundamental role in creating health-supportive environments. Plant landscapes, seating, pet-friendly facilities, waterside platforms, and open lawns for public access constitute secondary dimensions, with relative contributions ranging from 3.1% to 5.4%. The partial dependence plots of most attributes exhibit nonlinear associations. The pet-friendly facilities are presented in a two-step pattern in the partial dependence plot. This study proposes a conceptual reference framework for planning and offers exploratory proposals for waterfront recreation spaces.