Measured and Modeled C Flows after Land Use Change to Perennial Bioenergy Crops

In the first part of this Thesis the general concepts and state of art of the research subjects are introduced, then focusing on the impact of the land use change to perennial bioenergy crops on agricultural systems' carbon stocks. Then, the specific objectives of the research that has been carried out are stated. In the second part, the detailed methods and results of the four experiments performed are described one by one. All four papers constitute original research. The first and second papers originate from direct field measurements investigating the carbon flows subsequent to the establishment of perennial grasses for bioenergy on, respectively, a fertile agricultural land and a marginal land resembling, since it had been cultivated with poplar for the previous thirty years, the conditions of a biomass supply district. The third and fourth papers originate from model simulations investigating the potential of perennial biomass crops to produce energy and second-generation biofuels at the regional scale and their impact on soil carbon stocks and, more generally, on greenhouse gases emissions. Finally, by converging the findings of all the four experiments, general conclusions are drawn, also underlying future perspectives, current gaps and further research needed in order to fill these gaps.