Species-Specific Relationships Between Climatic Factors and Sanitary Felling Intensity in Urban Forests

Climate change and increasing climate extremes can jeopardise the stability of urban forest ecosystems, damage trees and cause their decline and death. The aim of this study was to analyse the intensity and causes of sanitary felling and their correlations with climate variables and age of sessile oak (Quercus petraea), common beech (Fagus sylvatica), European hornbeam (Carpinus betulus) and black locust (Robinia pseudoacacia) in urban forests in the City of Zagreb in the period 1994–2020. The intensity of sanitary felling was analysed based on the listed causes and correlated with temperature, precipitation, wind speed, drought indices and tree age. The results revealed species-specific differences in sanitary felling intensity and its associations with selected climatic variables and stand age. Statistically significant correlations were identified between sanitary felling intensity and precipitation anomalies in sessile oak and black locust and between sanitary felling intensity and mean annual air temperature in common beech. However, these associations should not be interpreted as evidence of direct climatic effects on tree mortality, as sanitary felling is also influenced by management decisions and local environmental conditions. The findings highlight the value of long-term sanitary felling records for identifying patterns of tree removal and their associations with climatic variability in urban forests.