TY - RPRT TI - Spatially robust estimates of biological nitrogen (N) fixation imply substantial human alteration of the tropical N cycle AU - Benjamin W. Sullivan AU - William K. Smith AU - Alan R. Townsend AU - Megan K. Nasto AU - Sasha C. Reed AU - Robin L. Chazdon AU - Cory C. Cleveland PY - 2014 DO - 10.1073/pnas.1320646111 UR - https://pubs.usgs.gov/publication/70126043 ID - 70126043 ER -