Effects of Plant Diversity and Management on Nitrogen Retention in Perennial Biomass Production Systems

There is increasing pressure on agroecosystems to provide fuel in addition to food. In order to sustainably meet these demands, we must improve the nitrogen use efficiency (NUE) of crops because of the high costs of producing N-fertilizers and the loss of nitrogen to water and atmospheric sinks can be a major problem. One way to achieve this is to use cropping systems that are inherently N-use efficient. Switchgrass and diverse prairie are two such cropping systems that are currently being considered for cellulosic feedstock production. While much is known about these ecosystems in unmanaged settings, it is imperative to understand how biomass can be produced, fertilized, and harvested without reducing their NUE and inherent abilities to recycle N. Biomass yields, efficient use of fertilizers, harvest efficiencies, and harvest schedules that produce adequate yields, but also retain N in the ecosystem, are some of the major constraints of sustainably producing biomass (Sanderson et al., 2006)…more

Authors: Laura Smith and Randy Jackson