Objective  Urban parks are the main places of daily social interaction for the elderly, and the quality of park environment plays an important role in promoting social interaction and improving the mental state of the elderly. In the context of the rapid development of population aging trend in China, it is of great practical significance to explore the influence of urban park environment on the mental health of the elderly under the severe winter climate in cold cities.

Methods  This research firstly proposes a hypothesis regarding the influence of urban park environment on the mental health of the elderly, and then conducts a field questionnaire targeting urban parks in Jilin City. After that, the research conducts a descriptive statistical analysis on the survey data obtained by SPSS 23.0 and an exploratory factor analysis and validation factor analysis on the survey data by SPSS 23.0 and AMOS 26.0 to assess data reliability and validity. Finally, by constructing a structural equation model, the research analyzes the influence of the natural and artificial environmental elements of urban parks in cold regions on the mental health of the elderly, as well as the mediating role played by the social interaction of the elderly therein.

Results  It can be seen from the descriptive statistical analysis of the survey data that the elderly generally spend two to three hours per day in the park, and typically participate in social activities with one to three partners; 63% of the elderly keep in touch with their friends in the park by mutual visiting and greeting call. Based on the factor analysis on relevant data, the research extracts four common factors, which have a cumulative contribution of 65.010%, indicating that they can reflect the original data more adequately and have good structural validity. Most of the loading coefficients for each factor are above 0.5, and the Cronbach’s α coefficient for each factor ranges from 0.789 to 0.933, indicating that all the factors are of good reliability. The research also analyzes the operating path of the structural equation model. The results indicate that the path significance of natural environment on mental health is 0.153, which is not significant. The estimated effect of artificial environment on mental health is 0.229. The estimated effect of natural environment on social interaction is –0.285. The estimated effect of artificial environment on social interaction is 0.436. And the estimated effect of social interaction on mental health is 0.755. The mediating effect of social interaction in the natural environment on the mental health of the elderly is –0.190; the mediating effect of social interaction in the artificial environment on the mental health of the elderly is 0.412, which is significant at the 95% confidence interval.

Conclusion  Based on the results of the above empirical study, the research tests the previously proposed hypothesis, and the findings are as follows. 1) For urban parks in cold regions, the natural environment may have a negative influence on the mental health of the elderly. Although this is inconsistent with the findings of some previous studies, it can still be inferred that the natural environment of urban parks in cold regions is not a major contributor to social interaction or mental well-being of the elderly. 2) The artificial environment of urban parks in cold regions may directly promote the mental health and indirectly promote the social interaction of the elderly. The adequacy of activity space plays the most important role in influencing both the mental health and social interaction of the elderly, followed by the adequacy of rest facilities, with the convenience facilities being the smallest influence factor. 3) Social interaction among the elderly has a great contribution to their mental health and plays a significant mediating role in the influence of urban park environment on mental health. Among the factors of “social interaction among the elderly”, the factor loadings of “frequency of social activities” and “contact with friends” are relatively large, indicating that the aforesaid two factors are the main influence factors of social interaction among the elderly, followed by “number of activity partners” and “days of activity per week”, with “hours of activity per day” being the smallest influence factor. So it is evident that the quality of social interaction activities plays a greater role in the influence of social interaction on the mental health of the elderly relative to the frequency of park visits. The effect value of the artificial environment of urban parks indirectly influencing the mental health of the elderly through interaction is greater than that of the artificial environment of urban parks directly influencing the mental health of the elderly, with social interaction playing a significant mediating role therein.