Socio-economic factors, climate, and people’s behaviours determine urban tree health

Urban trees provide numerous benefits, including improved air quality, reduced urban heat, and enhanced well-being for city dwellers. However, the distribution of these benefits is often uneven, with wealthy urban areas typically receiving greater advantages than poorer urban areas, highlighting a trend of green inequality in urban environments. The health of urban trees, which is crucial for maintaining environmental and social benefits, is likely affected by the interactive effects of socio-economic factors and climatic conditions. Yet, empirical research demonstrating these complex interactions is lacking, leaving a significant gap in our understanding of urban forest dynamics. In this study, we assessed the relationships between socio-economic factors, climate variables and people's behaviours with urban tree health across 11 suburbs along a climate gradient in Sydney, Australia. Additionally, we evaluated people's perceptions towards urban trees. Our analysis revealed that suburbs with high economic resources, precipitation and temperature were associated with healthier urban tree communities. Additionally, we found that suburbs where residents reported that they were actively engaged in tree care practices, such as providing water and fertiliser or mulch, also exhibited healthier trees. Our research uncovered significant differences in public perception and tree care practices across the studied suburbs. These variations appeared to be influenced by both socio-economic factors and local climate conditions, suggesting a complex interplay among socio-economic resources, climatic conditions and human behaviour in shaping and determining urban tree health. Our research underscores the need for targeted urban forestry strategies that address green inequalities and promote equitable distribution of urban forest benefits across diverse city landscapes.