I find it of paramount importance that students learn how to communicate their research. Summarizing their ideas and findings for a broad audience challenges them to keep the ‘why’ in mind for their research, and reminds them they are part of a bigger effort to solve the remaining mysteries of our world. In this mini series, all master students of this academic year present their work in around 300 words. Number five: Lore Hostens.
Dark diversity – what drives the absence of species in a Scandinavian tundra?
Several factors can cause the local diversity to decrease. The term “dark diversity” covers the plant species that are missing from an area but could be there based on their climatic niche. In this thesis, the dark diversity of the Scandinavian tundra will be studied. Based on extensive vegetation surveys in the northern part of the Scandes mountain range, over the years a good knowledge of the fine-scaled distribution (presence and absence) of plant species has been obtained. To find which species are part of the dark diversity, Species Distribution Models will be made for all common species in the flora, linking the presence/absence data of species distributions to high-resolution climate variables. This way, we can predict at the plot-level which species could be expected there based on their climatic niche.
Next, we will dig into the reason why these species are absent in that specific plot. We will distinguish between natural factors, such as soil characteristics (pH, available nutrients) and the functional traits of the species under study, and factors related to anthropogenic disturbances. We’ll look at the distance from linear disturbances to see whether it impacts the species composition in the plots. Some species can be very vulnerable to anthropogenic disturbances whereas others are not. Perhaps there is a link with the status of the absent species, meaning whether they naturally occur in the region (native species) or have been introduced (alien species). It could be that more native species are missing from highly disturbed plots and more alien from undisturbed plots.
Results from these analyses will be connected with conservation. What drives the absence of species most? Is it the anthropogenic factors like linear distance from roads? Or is it natural factors such as soil characteristics? Or a combination? With this, a conservation management plan can be suggested. Perhaps reducing anthropogenic disturbance impacts the local flora positively. Hopefully, this research will provide a picture of the dark diversity of the Scandinavian tundra and if the missing species can inform management decisions.