title: Carbon fluxes from an urban tropical grassland.
abstract: Turfgrass covers a large fraction of the urbanized landscape, but the carbon exchange of urban lawns is poorly understood. We used eddy covariance and flux chambers in a grassland field manipulative experiment to quantify the carbon mass balance in a Singapore tropical turfgrass. We also assessed how management and variations in environmental factors influenced CO2 respiration. Standing aboveground turfgrass biomass was 80 gC m(-2), with a mean ecosystem respiration of 7.9 ± 1.1 μmol m(-2) s(-1). The contribution of autotrophic respiration was 49-76% of total ecosystem respiration. Both chamber and eddy covariance measurements suggest the system was in approximate carbon balance. While we did not observe a significant relationship between the respiration rates and soil temperature or moisture, daytime fluxes increased during the rainy interval, indicating strong overall moisture sensitivity. Turfgrass biomass is small, but given its abundance across the urban landscape, it significantly influences diurnal CO2 concentrations.
authors.affiliation: Department of Geography, National University of Singapore, Singapore.
authors.forename: B J L
authors.initials: BJL
authors.lastname: Ng
authors.affiliation: Boston University, Department of Earth and Environment, Boston, MA, USA. Electronic address: lrhutyra@bu.edu.
authors.forename: L R
authors.initials: LR
authors.lastname: Hutyra
authors.affiliation: Boston University, Department of Earth and Environment, Boston, MA, USA.
authors.forename: H
authors.initials: H
authors.lastname: Nguyen
authors.affiliation: Singapore-MIT Alliance for Research and Technology, Center for Environmental Sensing and Modeling, 1 CREATE Way, Singapore.
authors.forename: A R
authors.initials: AR
authors.lastname: Cobb
authors.affiliation: Singapore-MIT Alliance for Research and Technology, Center for Environmental Sensing and Modeling, 1 CREATE Way, Singapore.
authors.forename: F M
authors.initials: FM
authors.lastname: Kai
authors.affiliation: Singapore-MIT Alliance for Research and Technology, Center for Environmental Sensing and Modeling, 1 CREATE Way, Singapore; Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, Cambridge, MA, USA.
authors.forename: C
authors.initials: C
authors.lastname: Harvey
authors.affiliation: Singapore-MIT Alliance for Research and Technology, Center for Environmental Sensing and Modeling, 1 CREATE Way, Singapore; Université de Toulouse: UPS, INP, EcoLab (Laboratoire Ecologie fonctionnelle et Environnement), ENSAT, Avenue de l'Agrobiopôle, F-31326 Castanet-Tolosan, France; CNRS, EcoLab, F-31326 Castanet-Tolosan, France.
authors.forename: L
authors.initials: L
authors.lastname: Gandois
mesh_terms: D002244:Carbon / Q000032:analysis* / Q000737:chemistry; D057486:Carbon Cycle; D002245:Carbon Dioxide / Q000032:analysis / Q000378:metabolism; D017753:Ecosystem; D006109:Poaceae / Q000378:metabolism*; D011891:Rain; D012846:Singapore; D012987:Soil / Q000737:chemistry; D013696:Temperature
chemical_list: D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon
keywords: CO(2) flux; Lawn; Respiration; Soil; Turf; Urban