Norway spruce shows stronger growth sensitivity and weaker intrinsic water-use efficiency response than Scots pine under increasing water limitation in southern Finland
Authors/Creators
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1.
Natural Resources Institute Finland
- 2. Natural Resources Institute Finland (Luke)
Description
Boreal forests are increasingly threatened by climate-induced water stress. This study examines how growing water limitation affected growth and intrinsic water-use efficiency (iWUE) in Scots pine and Norway spruce in southern Finland between 1990 and 2022. It combines tree-ring and carbon isotope data with growth indices from the Finnish National Forest Inventory. After 2016, Norway spruce showed pronounced growth declines, strongly constrained by vapour pressure deficit, and only limited physiological adjustment. Scots pine showed smaller growth reductions and a stronger increase in iWUE, indicating tighter stomatal regulation. Local moisture conditions further shaped these responses. Sustaining forest productivity and resilience will require site-adapted management that matches species selection to local soil and moisture conditions.