Effect of Heavy Rain Conditions on Throughfall in Evergreens and Conifers in Urban Settings

Abstract

Recently, an increase in precipitation defined as extreme rains has been recorded in many parts of the world. These rains have become a risk factor because of their characteristic duration, intensity, and amount, and the increased hazard of runoff and flooding, especially in urban settings. This study investigated throughfall caused by heavy rains of long duration (>5 h) and in high amounts (>10 mm) under broad-leaved evergreen and coniferous species in urban settings. In the study, throughfall was determined for a total of eight samples, four individuals from two different broad-leaved evergreen tree species and four individuals from two different coniferous tree species. During the eight-month study period, 11 rain events distributed over 20 days were evaluated. Findings showed that 61.88% and 55.24% of the throughfall was measured under the broad-leaved evergreen and coniferous species, respectively. Heavy rains did not make a difference between the throughfall under the broad-leaved evergreen and coniferous species (p>0.05). Likewise, there was no difference in the throughfall in the broad-leaved evergreen and coniferous species after the increase in duration and amount of heavy rains (p>0.05).