Carbon Capture in Urban Forests
Title: Comparison of Methods for Quantifying Carbon Sequestration in the Urban Forest of North Little Rock, Arkansas
Citation: Biological Engineering Transactions. 6(4): 221-231. 2014.
Authors: Heather N. Sandefur, Marty D. Matlock, Ryan Z. Johnston
Keywords: Carbon sequestration modeling, urban forest.
Abstract: Reducing net carbon emissions as part of a comprehensive greenhouse gas reduction strategy requires understanding and quantifying the carbon cycling within urban systems. This study estimated the annual rate of CO2 sequestration by the urban forest in the city of North Little Rock, Arkansas. The limited tree population data for this area, combined with a high level of heterogeneity in the density and distribution of the forest, posed unique challenges for estimating total annual carbon sequestration by trees within the city. For comparative purposes, two methods were used to calculate the average sequestration rate: the U.S. Forest Service Tree Carbon Calculator (CTCC) and a model based on canopy cover data obtained via remote sensing. An average sequestration rate of 18.1 MT CO2 year-1 ha-1 was calculated using the CTCC model, which was much higher than the average predicted by the satellite-based approach (8.5 MT CO2 year-1 ha-1). The overprediction of CO2 sequestration by the CTCC model can likely be attributed to the high tree density in North Little Rock. Because the CTCC model was designed for open-growth street trees, its application to trees in forest stands likely resulted in larger estimated tree volumes in these areas. The information presented is of potential use to municipal policymakers and could aid in land use valuation or other policy decisions that impact the urban forest in North Little Rock.
About the author:
Heather Sandefur is one of the founding principals of Paradigm Sustainability. You can find out more about Paradigm on our website.