Format: ORAL

Alfredo Di Filippo1,2,3, Andrea Caggegi1,2

1 DAFNE, Università della Tuscia, Viterbo, Italy 2 AgriTech - National Centre for Technology in Agriculture, Italy 3 National Geographic Society, Washington DC, USA

Primary forests, including old-growth forests, have a prominent role in biodiversity conservation. Furthermore, they represent a consistent repository of carbon in tree biomass and soil, making them critical regulators of the carbon cycle. Their ecological integrity strengthens their climate-change mitigation potential by fostering ecosystem stability as a C sink. Old trees are the most charismatic element of old-growth forests, harbouring large quantities of the overall biomass and contributing to forest biodiversity with unique arrays of microhabitats. We present the unique traits characterizing multi-century beech trees in a network of old-growth forests in the UNESCO Site 1133. We describe how traits change along environmental gradients and quantify their contribution to the forest carbon stock and sequestration, as well as the quantity and quality of biodiversity-hosting microhabitats. Tree-ring cores collected along the whole trees served to quantify tree conservation status in terms of response to climate change in the last decades. Old trees features were compared with data on exceptional tree distribution throughout managed landscapes gathered in a citizen science project promoted within the National Geographic-funded project Old But Gold: Restoring old-growth forests to build effective climate-change mitigating landscapes. Comparing natural and managed forests will help quantify the potential of human-altered landscapes to host old trees and the contribution of natural forest restoration to climate mitigation and biodiversity conservation.