Modellizzazione del ciclo del carbonio nelle praterie alpine: un caso di studio nelle Alpi Occidentali Italiane.

Understanding carbon dynamics in mountain environments is crucial to assess the effects of global climate change. Such environments are known to be net carbon sinks, they are the most a?ected by Global Warming through the mechanism of Elevation Dependent Warming, and are among the few ecosystems with low human colonization impact. Existing models representing carbon ?uxes in alpine zones still have low precision and often disagree with data. The purpose of this thesis is to build a representative model for landscape scale carbon ?uxes, the Landscape Carbon Model (LCM), concentrating on the case study of high-altitude alpine tundra of the Colle del Nivolet (2700m asl), located in the Western Alps of Italy. The LCM is spatially implicit and simulates soil humidity, pools and ?uxes of carbon from soil and vegetation. It implements the data-driven study of Magnani et al. (2020) in the structure of two validated numerical models: Williamson et al. (2006), for the dynamics of carbon pools, and Baudena et al. (2007), for the soil humidity. The model thus implemented is able to reproduce both the carbon dioxide emissions and uptake, measured in four sampling sites located at the Nivolet plain. I then explore future changes in high latitude alpine tundra in `what if' scenario projections. The net carbon uptake is observed to decrease under both temperature and precipitation rise scenarios, the two effects being almost independent.