This guide explains the potential impacts of climate change in Maryland and how they may affect woodlands. Management options are described for each of these climate change impacts to reduce or avoid loss of forest cover, declines in forest productivity, and reductions in the environmental benefits of woodlands.
The latest research on urban forests in the United States reveals that urban whole tree carbon storage densities average 7.69 kg C per m2 of tree cover and sequestration densities average 0.28 kg C per m2 of tree cover per year. Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million metric tons ($50.5 billion value; 95% CI = 597 million and 690 million metric tons) and annual sequestration is estimated at 25.6 million metric tons ($2.0 billion value; 95% CI = 23.7 million to 27.4 million metric tons). Estimates are presented by state and include the latest urban tree cover data and field data from urban areas across the United States.
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.
The i-Tree suite of models is designed to link research with local data on tree populations to assess the services and values provide by trees. The model is constantly being updated with new features and is being used globally. The model estimates numerous ecosystem services, disservices, and values, and includes estimates of tree carbon storage and annual sequestration, and their effects on building energy and consequent emissions from power plants. For more, please see the i-Tree tools page.