... UnitedStates woodland landscapes. Atmospheric Environment, 28,1197–1210.Guenther A, Greenberg J, Harley P et al. (1996) Leaf, branch,stand and landscape scale measurements of volatile organic CHANGES ... Aspens(Quaking and Bigtooth) and one Oak (Northern Red).DiscussionRapid changes in BVOC emissionsOur analysis suggests that between the 1980s and 1990s, a number of different factors combined ... because of some combinationof changes in land use, harvesting, and anthropogenicCO2or other pollution. Ecological succession, althougha natural process, was and is occurring so widelyFig....