Forecast and Assessment of Cropping sysTemS (FACTS) http://crops.extension.iastate.edu/facts/

Jason Kaye Biogeochemistry Lab: http://ecosystems.psu.edu/research/labs/kaye

David Lewis Biogoechemistry Lab: http://biology.usf.edu/ib/faculty/dlewis/

Vaclav Smil (one of the best thinkers/scientists out there): http://www.vaclavsmil.com/

Sustainable Corn: http://www.sustainablecorn.org