Dataset associated with: Increasing presence of non-native plants and arbuscular mycorrhizal fungi during a 10-year survey along subarctic mountains roads

Roads in cold climate mountains are known to be important vectors in the introduction and spread of non-native plant species. In the same context, mycorrhizal fungi communities are also altered by roads with a known positive effect on arbuscular mycorrhizal (AM) fungi diversity and abundance in disturbed roadsides. However, to what degree these two effects of roads are intertwined and how they are evolving over time is not well understood. In this study we conducted repeated surveys of non-native plants and AM fungi between 2012 and 2022, in the northern Scandes mountains to investigate temporal changes and interactions between roads, mycorrhizal fungi, and non-native plants. We found that the upward spread of non-native plants and lateral spread away from the roadside into the natural vegetation were so far extremely limited, with only two out of 23 non-native species showing an increase in their upper elevational limit. However, non-native plant species cover did increase over the ten year period, especially at lower elevations, and non-native richness increased from 17 to 23 species. Likewise, we saw an increase in AM fungal abundance over the last four years along the roadsides at lower elevations. Furthermore, our results suggest that increases in non-native species are unlikely to be the driving cause of the observed increase in AM fungal abundance, as AM fungi colonization varied independently of non-native species cover dynamics. 

This is the associated datasets and R-code. Check out the ReadMe.txt-file for information on the different files.

寒冷气候山区的道路素来被视作外来植物物种引入与扩散的重要媒介。在此背景下，道路同样会改变菌根真菌群落结构，且已知其对受干扰道路旁的丛枝菌根（arbuscular mycorrhizal, AM）真菌的多样性与丰度存在正向影响。然而，道路的这两类影响究竟在多大程度上相互交织，又随时间如何演变，目前仍未得到充分阐释。本研究于2012至2022年间，在斯堪的纳维亚北部山地针对外来植物与丛枝菌根真菌开展了多次调查，以探究道路、菌根真菌与外来植物间的动态变化及相互作用关系。研究结果显示，外来植物的向上扩散以及从道路侧向周边自然植被的扩散迄今仍极为有限：23种外来植物中仅2种的最高海拔分布上限出现上升。但在十年观测期内，外来植物的盖度确实有所提升，尤其在低海拔区域；同时外来植物的物种丰富度从17种增至23种。同样，在过去四年间，低海拔区域道路旁的丛枝菌根真菌丰度也出现了上升。此外，本研究结果表明，外来植物物种的增长并非观测到的丛枝菌根真菌丰度上升的驱动因素——因为丛枝菌根真菌的定殖率变化与外来植物盖度的动态变化相互独立。本研究附带相关数据集与R语言代码，各文件的详细说明请参阅ReadMe.txt文档。