New paper on the consequences of climate change for alpine grasslands
Climate warming is leading to earlier and longer growing seasons worldwide. Many plants sprout earlier in spring and benefit from warmer temperatures in autumn – so, the common opinion.
Patrick Möhl, Raphael von Büren and Erika Hiltbrunner now reveal in a paper in Nature Communications that this is not the case for the most common type of alpine grassland in the European Alps: earlier sprouting causes earlier senescence and therefore leads to 'brown mats' already in summer.
The study tested whether growth dynamics in this typical alpine grassland are altered when the naturally short growing season of 2–3 months is experimentally advanced and thus, prolonged by 2–4 months. Blocks of alpine vegetation were exposed to earlier summer conditions in the Phytotron Facility (link: https://ppe.duw.unibas.ch/en/phytotron/) and subsequently moved to the alpine field once the outdoor season started. Additional summer months did not extend the growing period, as canopy browning started 34–41 days after the start of the season, even when the growing season length was more than doubled. Less than 10% of roots were produced during the added months, suggesting that root growth was as conservative as leaf growth.
Publication link: https://www.nature.com/articles/s41467-022-35194-5