Growth and nutrient uptake of perennial crops in a paludicultural approach in a drained Mediterranean peatland

Combining peatland rewetting with biomass cropping (paludiculture) is one strategy to remove nutrientsurpluses from soil/water and stimulate peat-forming vegetation. This approach was tested in the Mas-saciuccoli Lake Basin (Tuscany, Italy), a coastal floodplain artificially drained for agricultural purposessince 1930, where land reclamation and continuous cropping have contributed to considerable peatdegradation and water eutrophication due to nutrient enrichment of surface waters. An experimentaltrial was established in spring 2012 with three perennial rhizomatous grasses (PRG) (Phragmites aus-tralis, Miscanthus × giganteus, Arundo donax) and two woody species managed as short-rotation coppice(SRC) (Salix alba “Dimitrios”, Populus × canadensis “Oudenberg”), aimed to provide biomass for variousbioenergy supply chains. A conventionally cultivated annual crop (maize) was the control. The aim of thisstudy was to compare the sustainability of the proposed paludiculture systems to that of conventionalannual crops on the basis of yield and nutrient-removal capability. This two-year field study evaluatedyields, nutrient concentrations and uptake (N and P) of the crops. Over the two years, A. donax had thehighest mean biomass yield (35 Mg ha−1), N uptake (367 kg ha−1), and P uptake (54 kg ha−1). SRCs hadthe lowest nutrient uptake in both years. Among grasses, the highest N concentration was recorded inA. donax leaves in 2013 (N: 2.41%), while P concentration was greater in S. alba branches (P: 0.39%). Theaverage aboveground biomass of maize was 17.5 Mg ha−1, while the nutrient uptakes were equal to 194and 27 kg ha−1for N and P, respectively.Thus, the performances of paludiculture systems were generally encouraging and could represent animportant alternative for restoring and managing former drained peatlands in a suitable product chain.