Carbon Cycle Impacts of Exurban Development
in Northern New England

Adam Wienert and Steve Hamburg

 

Increasing interest in enhancing terrestrial carbon sequestration to mitigate rising atmospheric CO2 levels requires a solid understanding of the terrestrial carbon cycle and how human activities, especially land-use change, impact carbon storage.  One of the most important land-use changes in the northeastern United States is exurban expansion, with the conversion of forestlands into low-density housing lots.  In order to understand the implications of this changing land-use within one of the strongest carbon sinks in the world the eastern forest biome of North America we quantified carbon stock losses due to increasing human disturbance associated with home construction within second-growth forests of central New Hampshire. 

We studied the development impacts of 148 house lots using lot characteristics derived from on-site measurements and tax data, in addition to regional ecological data, to construct lot-level carbon budgets.  The development of a house lot results, on average, in the loss of nearly 60 Mg C per lot over 50 years, with a range of 35 to 94 Mg C.  If each of the 6,500 homes built in New Hampshire each year causes this same scale of loss, the total carbon flux from home development equals nearly 8% of the states total carbon emissions from fossil fuels each year.  Policies to reduce sprawl associated with this development should be encouraged to reduce carbon emissions and promote climate-friendly land-use policies that allow for mitigation of rising atmospheric CO₂ concentrations. 

During lot development, human disturbances to the landscape that lead to carbon emissions include biomass removal and soil disturbance.

Updated 05/22/2008
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