Ontology highlight
ABSTRACT:
SUBMITTER: Liu J
PROVIDER: S-EPMC2867927 | biostudies-literature | 2010 Apr
REPOSITORIES: biostudies-literature
Liu Junguo J You Liangzhi L Amini Manouchehr M Obersteiner Michael M Herrero Mario M Zehnder Alexander J B AJ Yang Hong H
Proceedings of the National Academy of Sciences of the United States of America 20100412 17
Crop production is the single largest cause of human alteration of the global nitrogen cycle. We present a comprehensive assessment of global nitrogen flows in cropland for the year 2000 with a spatial resolution of 5 arc-minutes. We calculated a total nitrogen input (IN) of 136.60 trillion grams (Tg) of N per year, of which almost half is contributed by mineral nitrogen fertilizers, and a total nitrogen output (OUT) of 148.14 Tg of N per year, of which 55% is uptake by harvested crops and crop ...[more]