Revisiting the highways of the mountains

Posted on August 7, 2023 by lembrechtsjonas

In 2016, a significant endeavor began as we initiated the monitoring of vegetation along two cherished mountain trails in the Abisko region. Our primary objective was to assess the impact of these trails on the mountain vegetation. Specifically, we had a hunch that the trails might induce similar effects to what we had observed along roads: a notable reshuffling of mountain plants, allowing species to travel up and down the mountain, following the footsteps of hikers on the trails.

The team monitoring the vegetation on the bank of a little river, flowing noisily down from the best-studied mountain in the region: mount Nuolja

Understanding changes in species distribution becomes much smoother when tracking the same plants over an extended period. Therefore, it required persistence. With some resourceful juggling of funds and time, we succeeded in assembling the necessary crews to revisit these trails in 2018 and 2020 (though we have to admit, Covid almost thwarted our plans!).

Botanizing with a view on the slopes of Laktatjakka valley

Now, in 2023, our team has returned, fully recharged and eager to embark on another year of monitoring. To add to the excitement, we’ve welcomed new master students to our ranks, two of whom will delve into the intriguing topic of how these trails impact the vegetation.

Microclimate sensor, and one-meter survey plot with a pin-point frame. Pins are dropped 100 times in such a plot, and we write down every plant that is touched, to get an as objective as possible idea of the plant community in the plot.

Tist will focus on the temporal dynamics, paying close attention to non-native species. We already know that non-native species tend to thrive near trails worldwide, although perhaps not as fervently as they do near roadsides. In the northern Scandes, however, these non-native species seem to have been limited along the trails so far, possibly due to the extremely cold climate and the comparatively lower number of non-native species in European mountain regions. Nonetheless, such circumstances can change rapidly, which is why Tist will diligently monitor their movements: Are they reaching higher elevations in 2023 compared to 2016? Is their coverage increasing?

Microclimate sensor towards the top of the Laktatjakka trail. The nival zone is home to just a few species, such as the dwarf willow (Salix herbacea) and the glacier buttercup (Ranunculus glacialis). No home for non-native species, for sure, but never say never!

Meanwhile, Violetta will be investigating belowground, focusing on the crucial organisms known as mycorrhizae. We wonder whether our trails are affecting the mycorrhizal communities to a similar extent as roads do. The prevailing idea is that the impact on these communities will be noticeable but less intense than that observed along mountain roads due to the trails’ lower disturbance levels.

Microclimate sensor overlooking the valley in a typical alpine meadow. Most plants in this meadow are associated with the same mycorrhizal types, but the big unknown is what trail disturbance does with those assocations

Let the journey of discovery begin! Until then, our team will traverse those beautiful slopes in pursuit of botanical wonders, eager to unravel the secrets that lie beneath the canopy.