By Luca da Ros, IUCN CEM Young Professional.
Myself and colleague (Anna Bortolazzi), PhD students of forest ecology at the Free University of Bolzano (Italy), and others recently worked on a comprehensive review regarding the role of forest canopy in intercepting transforming and assimilating atmospheric nitrogen deposition. This work highlights how the canopy is not only a physical barrier between the atmosphere and the forest soil, but it is a relatively highly complex and living compartment, hosting multiple organisms and processes.
Numerous authors forecast severe impacts on forest ecosystem services and functioning when increasing anthropogenic N input exceeds both biotic and abiotic ecosystem holding capacity known as the N saturation process. However, most of the studies performed so far to quantify these impacts have largely neglected the potential role of the canopy – and associated biota – in biogeochemical processes.
In this review, we shed light on the possible role of the forest canopy in the N cycle, and we suggest that this element shall be included in those simulations aiming at forecasting the ecological consequence under the future scenario of increased N deposition (up to 50 times preindustrial levels for some areas of the world). Including this compartment could refine critical load calculation, therefore identifying with more precision which forest ecosystems are under the most severe threat. Ultimately, this would help policymakers prioritize intervention and management for highly susceptible forests to mitigate and cope with climate change.
You can access the details of our work here.
Luca Da Ros is a Ph D student with Faculty of science and technology, Free University of Bolzano/Bozen, Italy.