Humans have been affecting their environment since the
ancestors of Homo sapiens first walked upright, but never has their impact been
more detrimental than in the 21st century. "The loss of biodiversity has
much greater and more profound ecosystem impacts than had ever been
imagined," said David Tilman, professor of ecology, biodiversity and
ecosystem functioning at UC Santa Barbara's Bren School of Environmental
Science & Management.
Human-driven environmental disturbances, such as increasing
levels of reactive nitrogen and carbon dioxide (CO2), have multiple effects,
including changes in biodiversity, species composition, and ecosystem
functioning. Pieces of this puzzle have been widely examined but this new study
puts it all together by examining multiple elements. The results were published
July 1 in the Proceedings of the National Academy of Science.