Nitrogen Fertilization Effects on Productivity and Nitrogen Loss in Three Grass-Based Perennial Bioenergy Cropping Systems

摘要: Nitrogen (N) fertilization can greatly improve plant productivity but needs to be carefully managed avoid harmful environmental impacts. Nutrient management guidelines aimed at reducing forms of N loss such as nitrous oxide (N2O) emissions and nitrate (NO3-) leaching have been tailored for many cropping systems. The developing bioenergy industry is likely make use novel systems, polycultures perennial species, which we limited nutrient experience. We studied how a switchgrass (Panicum virgatum) monoculture, 5-species native grass mixture an 18-species restored prairie responded annual fertilizer applications 56 kg ha-1 in field-scale agronomic trial south-central Wisconsin over 2-year period. observed greater fertilizer-induced N2O sub-rooting zone NO3- concentrations the monoculture than either polyculture. Fertilization increased aboveground net primary polycultures, not monoculture. Switchgrass was generally more productive, while two did differ from each other or loss. Our results highlight differences between responding fertilization.