EFFECTS OF HEAVY RAINFALL ON STEMFLOW GENERATION IN SOME INDIVIDUAL TREES

Abstract

This study had two main objectives: to determine the stemflow generated by heavy rainfall in individual trees belonging to different species within a limited area in the same growing environment and to reveal the relationship between some morphological tree characteristics and the stemflow after these rains. In the study, an individual was selected from each of seven different species of trees and during the eight-month study period, stemflow measurements were made under conditions of natural rainfall that measured 10 mm and lasted more than 5 h. Over a period of 21 days, a total of 669.4 mm of rainfall was recorded for 12 storm events that met these conditions. Stemflow values from the specified trees were between 4.58 mm (0.68%) and 16.45 mm (2.45%). The lowest stemflow production occurred in P. nigra, and the highest in L. nobilis. The stemflow values, which were expected to be higher due to the high amount and long duration of the rainfall, did not support this prediction. There was a correlation between the amount of rainfall and the depth of stemflow (DSF) in all individuals, while there was a correlation between rainfall duration and DSF in all individuals except one (p <0.01, p <0.05). Although there was a correlation between the ratio of the stemflow depth to the amount of rainfall (RSFD / R) and the amount of rainfall in the C. libani, P. nigra, and Q. ilex individuals (p <0.01, p<0.05), there was a correlation (p <0.05) between the RSFD / R and the rainfall duration in C. libani, F. excelcior, P. nigra, and Q. ilex individuals. Relationships between some morphological tree characteristics and stemflow in heavy rain conditions were also determined in this study. Trunk diameter, projected canopy area, bark depth, and basal area were effective on DSF and RSFD / R (p <0.05), while tree height, leaf area index, and first branch height had no effect (p >0.05) on DSF or RSFD / R.