Factors Influencing the Health Status of Trees in Parks and Forests of Urbanized Areas

This research concerns the impact of air and soil pollution on the health status of selected tree species in parks and urban forests. The analysis was carried out over a decade, which allowed for creating the best models illustrating the impact of selective factors related to air and soil pollution on the health status of small-leaved limes, maples, oaks, and chestnut trees in the city. (1) Background and Objectives: The research aimed to identify the environmental factors that have the greatest impact on the health condition of trees in urban conditions and show which species are the most resistant to pollution in urban areas. The research object was 2441 individuals of four tree species inhabiting 11 parks and urban forests in Poznań. We assessed the trees in terms of dendrometric parameters and health status. Tree-stand soils were tested for P, K, Ca, Mg, and Na content using various analytical methods. Air data were obtained from a generally accessible WIOS website. The above data were statistically analyzed using one-way ANOVA and canonical correlation analysis (CCA). Our research has shown that unfavorable environmental parameters impact the health status of trees growing in urban areas. The most significant negative impact of O3 on the health of three out of four examined tree species was demonstrated. Other pollutants that affect the trees health include Mn (in the soil) and NO, NO2, CO, and C6H6 (in the air). Oak turned out to be the most resistant species to urban pollution. The area where chestnut trees grew turned out to be the most Fe, Mn, Na, and Pb soil-polluted and air-polluted with most of the substances recorded. The permissible concentration levels were exceeded in the case of tropospheric NOx, PM10, PM2.5, and Pb.