title: Decomposition and carbon storage of hardwood and softwood branches in laboratory-scale landfills.
abstract: Tree branches are an important component of yard waste disposed in U.S. municipal solid waste (MSW) landfills. The objective of this study was to characterize the anaerobic biodegradability of hardwood (HW) and softwood (SW) branches under simulated but optimized landfill conditions by measuring methane (CH4) yields, decay rates, the decomposition of cellulose, hemicellulose and organic carbon, as well as carbon storage factors (CSFs). Carbon conversions to CH4 and CO2 ranged from zero to 9.5% for SWs and 17.1 to 28.5% for HWs. When lipophilic or hydrophilic compounds present in some of the HW and SW samples were extracted, some samples showed increased biochemical methane potentials (BMPs). The average CH4 yield, carbon conversion, and CSF measured here, 59.4mLCH4g(-1) dry material, 13.9%, and 0.39gcarbonstoredg(-1) dry material, respectively, represent reasonable values for use in greenhouse gas inventories in the absence of detailed wood type/species data for landfilled yard waste.
authors.affiliation: Key Laboratory of Three Gorges Reservoir Region's Eco-Environment under Ministry of Education, Chongqing University, Chongqing 400044, China; Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908, United States. Electronic address: wangxiaoming@cqu.edu.cn.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Civil, Construction, and Environmental Engineering, Campus Box 7908, North Carolina State University, Raleigh, NC 27695-7908, United States.
authors.forename: Morton A
authors.initials: MA
authors.lastname: Barlaz
mesh_terms: D001673:Biodegradation, Environmental; D002244:Carbon / Q000032:analysis*; D057965:Carbon Sequestration; D002482:Cellulose; D008031:Lignin; D008697:Methane / Q000032:analysis; D012037:Refuse Disposal / Q000379:methods*; D062611:Solid Waste / Q000032:analysis; D064091:Waste Disposal Facilities; D014934:Wood / Q000737:chemistry*
chemical_list: D062611:Solid Waste; D002244:Carbon; D002482:Cellulose; D008031:Lignin; D008697:Methane
keywords: Anaerobic decomposition; Carbon storage; Hardwood and softwood branches; Landfills; Municipal solid waste