Diversity, productivity and landscape-level effects in North American grasslands managed for biomass production

Expanding markets for bioenergy will increasingly shape the composition and configuration of crop production. Growing interest in second-generation biofuels (e.g., lignocellulosic ethanol) is driving a discussion about the most productive and appropriate cropping systems. Interest in perennial grasslands as a bioenergy source has many people asking about the importance of plant community diversity in bolstering productivity, resistance to pest and pathogen pressure and wildlife habitat, among other ecosystem services. We review the current understanding of diversity-productivity relationships across multiple spatial scales, but also emphasize perspectives that have received less attention in the literature.