We assessed how climate change may impact the canopy hydrology of individual Pinus eldarica, Pinus brutia, and Cupressus arizonica trees planted in arid and semi-arid climates in Iran. Precipitation that reaches the forest floor as throughfall (TF) represents a significant portion of individual precipitation events (P_g ). We used a nondimensional relative sensitivity coefficient to examine the sensitivity of TF to changes in P_g . The Coupled Model Intercomparison Project phase 5 (CMIP5) HadGEM2-ES product was used under two emission scenarios (Representative Concentration Pathway (RCP) 2.6 and 8.5) to project yearly precipitation and P_g for the measurement sites from 2020–50. There was a strong linear relationship between TF and P_g at all sites [TF = 0.6 (P_g ) − 0.2; R ² = 0.9]. The arid P. eldarica trees showed the highest sensitivity coefficient (5.3) compared with semi-arid C. arizonica trees (1.6). The sensitivity coefficient approximately doubled for individual P. eldarica and C. arizonica trees in the arid climate relative to P. brutia and C. arizonica trees in the semi-arid climate. This suggests that TF under trees in the arid climate were more affected by changing P_g than in the semi-arid climate. Pinus eldarica trees planted in the dry climate exhibited the largest sensitivity coefficient differences (3.4) between small and large P_g . Changes in precipitation and increased smaller storm frequency are expected for arid and semi-arid regions. To buffer expected shifts in storm size due to climate change, it may be suitable to incorporate TF sensitivity when selecting trees for landscaping and urban greening.

我们评估了气候变化如何影响个人的树冠水文松eldarica，松brutia和绿干柏种植在干旱和半干旱气候在伊朗的树木。以穿透量（TF）的形式到达森林底层的降水代表了各个降水事件（P _g ）的很大一部分。我们使用一个无量纲的相对灵敏度系数来检查TF对P _g 变化的灵敏度。比较耦合模型比较项目第5阶段（CMIP5）的HadGEM2-ES产品用于两种排放情景（代表性浓度途径（RCP）2.6和8.5）以预测年降水量和P _g 适用于2020–50年的测量站点。在所有位点，TF和P _g 之间都存在很强的线性关系[TF  =  0.6（P _g ）-0.2; R ²＝ 0.9]。与半干旱C. arizonica树（1.6）相比，干旱的P. eldarica树显示出最高的灵敏度系数（5.3 ）。灵敏度系数近似加倍个别P. eldarica和C. arizonica树木气候相对于干旱在P. brutia和C. arizonica树木在半干旱气候。这表明干旱气候下树木下的TF受变化影响更大。P _g 比半干旱气候高。干旱气候下种植的松树在小和大P _g 之间表现出最大的灵敏度系数差异（3.4）。干旱和半干旱地区预计会有降水变化和较小的风暴频率。为了缓冲由于气候变化导致的暴风雨的预期变化，在为景观美化和城市绿化选择树木时，可能需要结合TF敏感性。