Drivers of plant community composition and species richness in Western Greenland

The Arctic experiences rapid climate change, but our ability to predict how this will influence plant communities is hampered by a lack of data on the extent to which different species are associated with particular environmental conditions, how these conditions are interlinked, and how they will change in coming years. Increasing temperatures may negatively affect plants associated with cold areas due to increased competition with warm-adapted species, but less so if local temperature variability is larger than the expected increase. Here we studied the potential drivers of vegetation composition and species richness along coast to inland and altitudinal gradients by the Nuuk fjord in western Greenland using Hierarchical Modelling of Species Communities (HMSC) and linear mixed models. Community composition was more strongly associated with random variability at intermediate spatial scales (among plot groups 500 m apart) than with large-scale variability in summer temperature, altitude ..., The study was conducted at five different sites along the Nuuk fjord (GodthÃ¥bsfjorden) in western Greenland. 
In 2011–2013, 414 permanent plots were established across the five study sites. The plots were circular, with a diameter of 2 m. Three groups of six plots were selected for every 100 m increase in altitude. The position of the first plot at each altitude was selected by walking uphill straight towards a pre-selected point until the isocline was reached (measured using a hand-held GPS). Plot centres were placed exactly 10 m apart along the isoclines, or slightly more if needed to prevent plots from being entirely in water or having an average slope >45°. Plot groups were placed exactly 500 m apart. The lowest plots were moved to 20 m a.s.l. to avoid exposure to salt. The highest altitudes used in sites 1–5 were 200, 200, 400, 500 and 500 m a.s.l., respectively, reflecting that the mountains are higher further east. The study design was the exact same as previously used in..., # Drivers of plant community composition and species richness in Western Greenland

Dataset DOI: [10.5061/dryad.8sf7m0d17](10.5061/dryad.8sf7m0d17)

**Principal Investigator Contact Information**

```
Name: Jacob Nabe-Nielsen

Institution: Aarhus University 

Email: [e-mail]
```

## Description of the data and file structure

This dataset contains the data required to replicate analyses in Nabe-Nielsen et al. (2025), studying the potential drivers of vegetation composition and species richness along coast to inland and altitudinal gradients by the Nuuk fjord in western Greenland using Hierarchical Modelling of Species Communities (HMSC) and linear mixed models. Data originate from five study sites along the Nuuk fjord in western Greenland. At each site three groups of six plots were selected for every 100 m increase in altitude. Plot centres were placed exactly 10 m apart along the isoclines, and plot groups were placed exactly 500 m apart. The permanently marked plots were circul...,