africa alberta animal-plantrelationships asia atmosphericcarbondioxide botany canada classification congresses ecologiaflorestal ecology ecophysiology effectofatmosphericcarbondioxideon effectofatmosphericdepositionon effectofgreenhousegaseson environmentalaspects ethnobotany forestanimals forestdeclines forestecology forestsandforestry forestsecology geographicaldistribution ghana greatbritain greenhousegases history identification industries minnesota mountainplants naturalhistory newengland newzealand northamerica nutrientcycles nutrition oak phytogeography plantnutrients plants rainforestecology southafrica trees unitedstates utilization vegetationdynamics woodlandgardenplants