An increased frequency of fire events on the Slovenian Karst is in line with future climate-change scenarios for drought-prone environments worldwide. It is therefore of the utmost importance to better understand tree-fire-climate interactions for predicting the impact of changing environment on tree functioning. To this purpose, we studied the post-fire effects on leaf development, leaf carbon isotope composition (ẟ¹³C), radial growth patterns and the xylem and phloem anatomy in undamaged (H-trees) and fire-damaged trees (F-trees) of Q. pubescens with good re-sprouting ability in spring 2017, the growing season after a rangeland fire in August 2016. We found that the fully developed canopy of F-trees reached only half of the LAI values measured in H-trees. Throughout the season, F-trees were characterised by higher water potential and stomatal conductivity and achieved higher photosynthetic rates compared to unburnt H-trees. The foliage of F-trees had more negative δ¹³C values than those of H-trees. This reflects that F-trees less frequently meet stomatal limitations due to reduced transpirational area and more favourable leaf-to-root ratio. In addition, the growth of leaves in F-trees relied more on the recent photosynthates than on reserves due to the fire disturbed starch accumulation in the previous season. Cambial production stopped 3 weeks later in F-trees, resulting in 60% and 22% wider xylem and phloem increments, respectively. A novel approach by including phloem anatomy in the analyses revealed that fire caused changes in conduit dimensions in the early phloem but not in the earlywood. However, premature formation of the tyloses in the earlywood vessels of the youngest two xylem increments in F-trees implies that xylem hydraulic integrity was also affected by heat. Analyses of secondary tissues showed that although xylem and phloem tissues are interlinked changes in their transport systems due to heat damage are not necessarily coordinated.

中文翻译：

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火后对毛栎（Quercus pubescens）的叶片和次生维管组织发育的影响。

斯洛文尼亚喀斯特地区发生火灾的频率越来越高，这与未来全球干旱多发的气候变化情景相吻合。因此，最重要的是更好地了解树木-火-气候之间的相互作用，以预测不断变化的环境对树木功能的影响。为此，我们研究了叶的发展，叶碳同位素组成后火焰效果（ẟ ¹³C），2017年春季（牧场火灾后的生长季节）具有良好重发芽能力的毛白栎的未损坏（H树）和火毁树（F树）的径向生长模式以及木质部和韧皮部解剖在2016年8月。我们发现，成熟的F树树冠仅达到了H树中LAI值的一半。在整个季节中，F树的水势和气孔电导率较高，与未燃烧的H树相比，光合速率更高。F-树的叶子有更多的负δ ¹³C值比H树大。这反映出由于减少的蒸腾面积和更有利的叶根比，F树较少遇到气孔限制。此外，由于火势干扰了前一个季节的淀粉积累，F树中叶片的生长更多地依赖于最近的光合产物而不是储备。3周后，F树停止了冈比亚的生产，木质部和韧皮部的增幅分别增加了60％和22％。在分析中包括韧皮部解剖学的一种新方法表明，火引起了韧皮部早期导管的尺寸变化，但早期木本没有。但是，在F树中最年轻的两个木质部增量中，早幼木质容器中的酪醇过早形成，这意味着木质部的水力完整性也受到热量的影响。