Mediterranean tree species have evolved to face seasonal water shortages, but may fail to cope with future increases in drought frequency and intensity. We investigated stem radial increment dynamics in two typical Mediterranean tree species, Aleppo pine (Pinus halepensis), a drought-avoiding species, and holm oak (Quercus ilex), a drought-tolerant species, in a mixed forest and on contrasting slope aspects (south- and north-facing). Intra- and inter-annual growth patterns were modelled using the VS-Lite2 model for each tree species and slope-aspect. Both species showed a bimodal growth pattern, with peaks coinciding with favourable conditions in spring and autumn. A bimodal growth pattern is always observed in P. halepensis, while in Q. ilex is facultative, which suggests different strategies adopted by these species to cope with summer drought. More specifically, trees on south-facing slope showed a more evident bimodal pattern and more intra-annual density fluctuations. In recent decades, the intensity of both growth peaks has diminished and drifted away due to the increased summer drought. The VS-Lite2 model reveals a niche partitioning between both species. Differences in growing season’s length and timings of growth peaks in both species are relevant for their coexistence and should be considered for estimating mixed-forest responses under climate change scenarios.

地中海树种已经面临季节性缺水的情况，但可能无法应对未来干旱频率和强度的增加。我们研究了两种典型地中海树种的茎干径向增量动态变化，这是在混合森林中和在坡度相反的情况下，两种典型的地中海树种，即抗干旱的阿勒颇松（Pinus halepensis）和一种耐干旱的霍姆橡树（Quercus ilex）。朝南和朝北）。使用VS-Lite2模型对每种树种和坡度进行了年度内和年度间生长模式的建模。两种物种都表现出双峰生长模式，在春季和秋季，峰与有利条件相吻合。在halepensis中总是观察到一种双峰型的生长模式，而在Q. ilex中总是观察到一种双峰型的生长模式。是兼收并蓄的，这表明这些物种为应对夏季干旱而采取了不同的策略。更具体地说，朝南坡上的树木表现出更明显的双峰模式和年内密度波动。在最近的几十年中，由于夏季干旱的增加，两个生长高峰的强度都减小了并逐渐消失。VS-Lite2模型揭示了两个物种之间的生态位分配。两种物种的生长季节长度和生长高峰时间的差异都与它们的共存有关，在估算气候变化情景下的混交林响应时应考虑这些差异。