Plant diversity dynamics over space and time in a warming Arctic

Area of Science:

• Ecology
• Climate Change Biology
• Arctic Studies

Background:

• The Arctic is warming rapidly, significantly faster than the global average.
• Arctic plant communities are known to be responding to warming through changes in species distribution and abundance.
• Quantifying local changes in Arctic plant diversity remains a critical research gap.

Purpose of the Study:

• To quantify temporal changes in Arctic plant species richness and composition.
• To identify the geographical, climatic, and biotic drivers of these observed changes.
• To assess whether Arctic plant communities are undergoing biotic homogenization.

Main Methods:

• Utilized a large dataset of 42,234 records for 490 vascular plant species from 2,174 Arctic plots.
• Conducted repeat surveys between 1981 and 2022 to analyze temporal changes.
• Employed statistical analyses to identify drivers of species richness and composition shifts.

Main Results:

• No average directional change in species richness was detected across the Arctic.
• Species turnover was prevalent, with 59% of plots showing gains and/or losses of species.
• Increased temperatures correlated with higher proportions of species gains and losses, while shrub expansion was linked to decreased species richness.

Conclusions:

• Arctic plant communities exhibit significant local changes in composition and richness, driven by warming and plant-plant interactions.
• Widespread species turnover indicates dynamic ecological responses rather than overall homogenization.
• These findings highlight the complex interplay of climate and biotic factors shaping Arctic ecosystems and have implications for biodiversity, ecosystem function, and human livelihoods.