With the northern Scandinavian branch of the Mountain Invasion Research Network (MIREN, www.mountaininvasions.org), we are studying the impact of roads and hiking trails on alpine and arctic ecosystems. Our goal is to better understand what kind of changes these man-made disturbances cause to the natural vegetation and through which mechanisms these changes happen.
MIREN’s focus is to look at changes in the distribution of species in mountain ecosystems across the world to help us better understand and manage the increasingly important shifts caused by global change. For us, this means studying these changes in the sub-arctic region of the Nothern-Scandes, along a network of roads and trails ranging from Narvik, Norway to Abisko, Sweden where we work in relation with the Abisko Scientific Research Station.

Studying tundra biodiversity in the northern Scandes
Our first approach is to closely monitor vegetation as well as climatic variables and biotic interactions. Regular vegetation surveys were made since 2012 to track the changes in vegetation along roads and trails and particularly the upward movement of lowland native and non-native species along these paths. Since 2017 we have also been looking into the interactions between plants and their natural symbionts, the mycorrhizal fungi, and how they change at the interface between natural vegetation and roads. Additionally, we have been monitoring climatic variables such as temperature and moisture through the use of small loggers spread over all our research sites which you might even come across during your next arctic hike.

Anthoxanthum odoratum, a lowland grass species surviving at high elevations in our experiments
However, observations only can only bring us so many answers, which is why we are also using experimental means to test out which mechanisms are behind these movement of plants we have observed. This is done by creating artificial gaps (disturbances, like in trail- or roadsides) in natural vegetation at different altitudes, in which we sow seeds of species known to be rapidly moving uphill, under different biotic and abiotic conditions. Their success will then be compared to the success of seeds planted under similar conditions but in absence of the simulated disturbance effect.

Disturbance experiment in the Laktajakka valley, northern Sweden
This project is supervised by Jonas Lembrechts (University of Antwerp), together with PhD student Jan Clavel, master students Sam Vastmans and Nell van den Plas. The project is done in the context of the global MIREN network, together with ther Climate Impact Research Center of the Abisko Research Station.