Effects of urban tree management and species selection on atmospheric carbon dioxide

The objectives of this study are 1) to determine how tree species under the same management and decomposition regime differ in net carbon benefits; 2) to illustrate for one species how maintenance activities, method of disposal/use of removed trees, and energy conservation by trees can affect the timing and overall carbon benefits derived from urban trees; and 3) to present management strategies that optimize the net impact of urban forestry on reducing atmospheric carbon dioxide. [UMN]

"Trees sequester and store carbon in their tissue at differing rates and amounts based on such factors as tree size at maturity, life span, and growth rate. Concurrently, tree care practices release carbon back to the atmosphere based on fossil-fuel emissions from maintenance equipment (e.g.,chain saws, trucks, chippers). Management choices such as tree locations for energy conservation and tree disposal methods after removal also affect the net carbon effect of the urban forest. Different species, decomposition, energy conservation, and maintenance scenarios were evaluated to determine how these factors influence the net carbon impact of urban forests and their management. If carbon (via fossil-fuel combustion) is used to maintain vegetation structure and health, urban forest ecosystems eventually will become net emitters of carbon unless secondary carbon reductions (e.g., energy conservation) or limiting decomposition via long-term carbon storage (e.g., wood products, landfills) can be accomplished to offset the maintenance carbon emissions. Management practices to maximize the net benefits of urban forests on atmospheric carbon dioxide are discussed." [Abstract]