"Trace elements." . . . . . . . . . . . . . . . "Global changes in biogeochemical cycles in response to human activities : final report"@en . . . . . . . . . . . . . . . . . . . "Global changes in biogeochemical cycles in response to human activities final report"@en . . . "Biogeochemistry." . . "Atmospheric composition." . . "Ecosystems." . . "Nitrogen." . . "Biosphere." . . "Carbon." . .