Human Appropriation of the Products of Photosynthesis Nearly 40 % of potential terrestrial net primary productivity is used directly , co-opted , or foregone because of human activities

@inproceedings{Vitousek2007HumanAO,
  title={Human Appropriation of the Products of Photosynthesis Nearly 40 % of potential terrestrial net primary productivity is used directly , co-opted , or foregone because of human activities},
  author={Peter M Vitousek and Paul R. Ehrlich and Anne H. Ehrlich and Pamela Ann Matson},
  year={2007}
}