Estimating carbon storage in windbreak trees on U.S. agricultural lands

Abstract

Assessing carbon (C) capture and storage potential by the agroforestry practice of windbreaks has been limited. This is due, in part, to a lack of suitable data and associated models for estimating tree biomass and C for species growing under more open- grown conditions such as windbreaks in the Central PlainsregionoftheUnitedStates (U.S.).Weevaluated 15 allometric models using destructively sampled Pinus ponderosa (Lawson & C. Lawson) data from field windbreaks in Nebraska and Montana. Several goodness-of-fit metrics were used to select the optimal model. The Jenkins' et al. model was then used to estimate biomass for 16 tree species in windbreaks projected over a 50 year time horizon in nine conti- nental U.S. regions. Carbon storage potential in the windbreak scenarios ranged from 1.07 ± 0.21 to 3.84 ± 0.04 Mg C ha -1 year -1 for conifer species and from 0.99 ± 0.16 to 13.6 ± 7.72 Mg C ha -1 year -1 for broadleaved deciduous species during the 50 year period. Estimated mean C storage potentials across species and regions were 2.45 ± 0.42 and 4.39 ± 1.74 Mg C ha -1 year -1 forconifer and broad- leaved deciduous species, respectively. Such infor- mation enhances our capacity to better predict the C sequestration potential of windbreaks associated with whole farm/ranch operations in the U.S.