The effects of local and regional environmental variables as well as spatial gradients on the plant species composition of two types of alder-dominated forests (riparian forests and alder carrs) with contrasting connectivity were studied across the Western Carpathians from Hungary through Slovakia to Poland. We used large vegetation (240 sampling plots) and environmental (24 variables) datasets, which were accompanied by spatial variables represented by principal coordinates of neighbour matrices. Canonical correspondence analysis (CCA) of the two datasets revealed 13 and 29 variables with significant effects on variation in species composition of alder carrs and riparian alder forests, which jointly explained 41.2% and 36.4% of the variability, respectively. Altitude was the most important factor explaining 7.7% of the variability in the species composition of alder carrs and 8.2% in riparian alder forests. Variation partitioning in CCA revealed that local variables were crucial drivers for species composition patterns in alder carrs, while spatial processes unrelated to the measured environmental variables shaped the vegetation structure of riparian forests.

中文翻译：

---

连通性相反的al木为主森林中植物物种组成的驱动因素

研究了从匈牙利到斯洛伐克，从波兰到斯洛伐克的整个喀尔巴阡山脉，研究了局部和区域环境变量以及空间梯度对两种类型的以al木为主的森林（河岸森林和al木森林）的植物物种组成的影响。我们使用了大型植被（240个采样区）和环境（24个变量）数据集，这些数据集都包含了由相邻矩阵的主坐标表示的空间变量。两个数据集的规范对应分析（CCA）显示13个和29个变量对al木和河岸al木森林的物种组成变化具有显着影响，共同解释了这些变化的41.2％和36.4％。海拔高度是解释7的最重要因素。der鱼物种组成变异的7％，在河岸al木森林中为8.2％。CCA中的变化分区显示，局部变量是al木鱼类物种组成模式的关键驱动因素，而与测得的环境变量无关的空间过程塑造了河岸森林的植被结构。