The expansion of shrubs represents one of the most widely observed responses of Arctic ecosystems to the rapid climate change. This shrubification is impacting Arctic soil carbon (C) stocks, a major terrestrial C reservoir. Shrubification is commonly assumed to enhance C uptake and C stocks through accelerated photosynthesis due to the high leaf area of shrubs. However, shrubification may also be associated with accelerated net C emissions through changes in plant and microbial community composition, soil temperature and nutrient availability. This project investigates the impact of shrubification on Arctic C balance by integrating new year-round ecosystem and soil carbon flux measurements at the site level with a synthesis database spanning the circumpolar Arctic. It produces new knowledge about Arctic C balance and potential C emissions associated with shrubification, contributing to a better understanding of climate change impacts and feedbacks.

2025

2029