The quantification of climate–growth relationships is a fundamental step in tree-ring sciences. This allows the assessment of functional responses to climate warming, particularly in biodiversity and climate-change hotspots including the Mediterranean Basin. In this region, broadleaf tree and shrub species of pre-Mediterranean, subtropical origin, have to withstand increased aridification trends. However, they have not been widely studied to assess their long-term growth responses to climate and drought. Since these species evolved under less seasonal and wetter conditions than strictly Mediterranean species, we hypothesized that their growth would mainly respond to higher precipitation and water availability from spring to early summer. Here, we quantified climate–growth relationships in five of these broadleaf species showing different leaf phenology and wood type (Pistacia terebinthus L., Pistacia lentiscus L., Arbutus unedo L., Celtis australis L., and Laurus nobilis L.) by using dendrochronology. We calculated Pearson correlations between crossdated, indexed, mean ring width series of each species (chronologies) and monthly climate variables (mean temperature, total precipitation). We also calculated correlations between the species’ chronologies and a drought index on 7-day scales. Lastly, we compared the correlation analyses with “climwin” analyses based on an information-theoretic approach and subjected to cross-validation and randomization tests. As expected, the growth of all species was enhanced in response to wet and cool conditions during spring and early summer. In some species (P. lentiscus, A. unedo, C. australis,) high prior-winter precipitation also enhanced growth. Growth of most species strongly responded to 9-month droughts and the correlations peaked from May to July, except in L. nobilis which showed moderate responses. The “climwin” analyses refined the correlation analyses by (i) showing the higher explanatory power of precipitation (30%) vs. temperature (7%) models, (ii) selecting the most influential climate windows with June as the median month, and (iii) providing significant support to the precipitation model in the case of P. terebinthus confirming that the radial growth of this species is a robust proxy of hydroclimate variability. We argue that “climwin” and similar frameworks based on information-theoretic approaches should be applied by dendroecologists to critically assess and quantify climate–growth relationships in woody plants with dendrochronological potential.

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与阔叶地中海树木和灌木树种的气候，干旱和径向生长相关：量化气候与生长关系的新方法

气候-增长关系的量化是树木年轮科学的基本步骤。这可以评估对气候变暖的功能响应，尤其是在包括地中海盆地在内的生物多样性和气候变化热点地区。在该地区，地中海前亚热带起源的阔叶树和灌木物种必须承受日益增加的干旱化趋势。但是，尚未对其进行广泛的研究以评估其对气候和干旱的长期增长响应。由于这些物种在比严格的地中海物种更少的季节性和湿润条件下进化，因此我们假设它们的生长将主要对春季至初夏期间更高的降水量和水利用量做出响应。这里，黄连木terebinthus L.，夏季黄连木L.，杨梅unedo L.，朴树芦苇L.，和月桂L.）通过使用树轮。我们计算了每个物种的交叉，索引，平均环宽系列（时间顺序）与每月气候变量（平均温度，总降水量）之间的皮尔森相关性。我们还计算了该物种的时间序列与7天尺度上的干旱指数之间的相关性。最后，我们将相关分析与“ climwin”基于信息理论方法进行分析，并经过交叉验证和随机化测试。不出所料，春季和初夏期间，由于潮湿和凉爽的条件，所有物种的生长都得到了增强。在一些物种（P. lentiscus，A. unedo，C.芦苇，）现有冬季高沉淀也增强的生长。多数物种的生长对9个月的干旱有强烈的响应，并且相关性从5月到7月达到顶峰，除了诺贝利杯中表现出中等响应。该“ climwin”的分析通过（i）显示了较高的解释力（30％）相对于温度（7％）模型来解释相关分析，（ii）选择以6月为中值月份的最具影响力的气候窗口，以及（iii）在P. terebinthus的情况下，为降水模型提供了重要的支持，证实了该物种的径向生长是水气候变化的有力替代。我们认为，树状生态学家应该采用基于信息论方法的“ climwin ”和类似框架，以严格评估和量化具有树状年代学潜力的木本植物的气候-生长关系。