title: Greenhouse gas emissions and the interrelation of urban and forest sectors in reclaiming one hectare of land in the Pacific Northwest.
abstract: The interrelation between urban areas and land use options for greenhouse gas mitigation was evaluated by assessing the utility of urban residuals for soil reclamation. Long-term impacts on soil C storage for mine lands restored with urban organic residuals were quantified by sampling historic sites reclaimed both conventionally and with residuals-based amendments. Use of amendments resulted in greater C storage compared to conventional practices for all sites sampled, with increases ranging from 14.2 Mg C ha(-1) in a coalmine in WA to 38.4 Mg C ha(-1) for a copper mine in British Columbia. Expressed as Mg C per Mg amendment, effective C increases ranged from 0.03 to 0.31 Mg C per Mg amendment. Results were applied to three alternative land-use scenarios to model the net GHG balance for a site restored to forest or low-density development. The model included construction of 3.9 243 m(2)-homes, typical of urban sprawl. Emissions for home and road construction and use over a 30-year period resulted in net emissions of 1269 Mg CO2. In contrast, conventional reclamation to forestland or reclamation with 100 Mg of residuals resulted in net GHG reductions of -293 and -475 Mg CO2. Construction of an equivalent number of smaller homes in an urban core coupled with restoration of 1 ha with amendments was close to carbon neutral. These results indicate that targeted use of urban residuals for forest reclamation, coupled with high-density development, can increase GHG mitigation across both sectors.
authors.affiliation: SYLVIS Environmental, 427 Seventh Street, New Westminster, BC V3M 3L2, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Trlica
authors.forename: Sally
authors.initials: S
authors.lastname: Brown
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002244:Carbon / Q000032:analysis; D002245:Carbon Dioxide / Q000032:analysis*; D057965:Carbon Sequestration; D002947:Cities; D060389:Construction Industry; D052918:Environmental Restoration and Remediation; D017752:Greenhouse Effect; D006798:Housing; D008962:Models, Theoretical; D015205:Northwestern United States; D012987:Soil / Q000737:chemistry; D014197:Trees
chemical_list: D000393:Air Pollutants; D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon