Influence of Stem Distance on Spatial Partitioning of Throughfall

Abstract

The variation of throughfall depending on the distance from the tree stem in a region with semiarid climate characteristics was determined in this study. Data were obtained from a total of 24 sample coniferous trees, and field monitoring was carried out over a period of more than 1 year. In the study, throughfall was determined from spatial points located 0.5 and 2 meters away from the stem. The results revealed that the throughfall increased from the stems to the edge of the canopy. Throughfall occurring close to the tree trunk constitutes 36.34% of the total precipitation. However, in the sections close to the tip of the branches, 59.33% of the throughfall occurred. Throughfall also showed heterogeneous distributions with both black pine and cedar, varying depending on the distance from the stems. The throughfall ratio near the stem was 39.73% in black pine and 32.95% in cedar, whereas near the canopy edge these values were 58.07% and 60.59%, respectively. Within cedars, the variation of throughfall between their stems and branch tips was higher. It is observed that spatial differences are effective in the partitioning of throughfall within coniferous species. It is anticipated that by conducting similar studies under different stand and climate conditions, the spatial distribution of throughfall could be better understood. © 2026 Istanbul University-Cerrahpasa. All rights reserved.