Seasonal Variability of Rainfall Interception under Individual Ash Trees Afforested in a Semiarid Climate, Chitgar Forest Park, Tehran

Recently, the most important topic in water management was to determine the effects of urban forests and green space on partitioning gross rainfall (GR) into the rainfall interception (I), stemflow (SF), and throughfall (TF). The main aim of this research was to quantify the seasonal variations [Growing Season (GS), and Non-Growing Season (NGS)]) in I by individual Fraxinus rotundifolia trees in the Chitgar Forest Park located in a semiarid climate zone of Iran. From the September 2012 to September 2013, GR and TF were collected through 6 and 12 rain-gauges, respectively. I was calculated as the difference between GR and TF. Fifty rainfall events were recorded and the cumulative GR was measured 156.0 mm. Over the study period, GS, and NGS, I ranged 19.4%, 23.0%, and 16.2%, respectively. Significant positive correlations were observed between I and GR over study period (R= 0.862), GS (R= 0.862), and NGS (R= 0.950) (p