Research Fellows Directory
Maria Rosa (Rossella) Guerrieri
Dr Maria Rosa (Rossella) Guerrieri
University of Edinburgh
My scientific interests focus on the responses of forests to global changes (i.e., nitrogen deposition, increase of drought conditions in the Mediterranean region, limitations at treeline ecotone). Current research as Newton International Fellow at the School of GeoSciences aims to understand the impact of the human-induced increase of nitrogen deposition (Ndep) on the carbon (C) and nitrogen (N) cycles in forest ecosystems.
Why should we care about nitrogen deposition? The growing demand for food and energy production, driven by the increase in global population, has led to a remarkable rise in the emission of reactive N in the atmosphere by over a factor of 10 compared to the late-19th century. The return of reactive N from the atmosphere to the biosphere through Ndep has led to a significant alteration of the N cycle and of its interaction with the C cycle in forest ecosystems.
Consequences of Ndep for forest ecosystems. Forests store about 25% of the CO2 emitted by land use change and fossil-fuels combustion, thus contributing to the mitigation of climate change. Indeed, tree growth and biomass production in many ecosystems is N-limited (i.e., temperate and boreal forests), so increased Ndep would allow increased fixation of CO2 by trees, thus enhancing the terrestrial C ‘sink’. However, the amount of enhanced C uptake by N-limited forests that can be attributed to Ndep (i.e., the indirect human-induced C-sink) has been hotly debated. One of the main unresolved issues is whether Ndep is transformed and absorbed by tree canopies, a process excluded in previous experiments.
Research during my Newton International Fellowship aims to investigate canopy N processes and the way they link C and N cycles in forests. Hence, in addition to contribute to the ongoing scientific debate, my study will provide a more comprehensive understanding of the indirect human-induced C-sink, with crucial implications for the implementation of the Kyoto protocol.
Interests and expertise (Subject groups)