World carbon problem.
D000388:Air / Q000032:analysis; D001419:Bacteria / Q000378:metabolism; D002244:Carbon; D002245:Carbon Dioxide / Q000378:metabolism; D056890:Eukaryota / Q000378:metabolism; D005523:Food Supply; D010578:Petroleum; D012722:Sewage
D010578:Petroleum; D012722:Sewage; D002245:Carbon Dioxide; D002244:Carbon