title: Carbon emission and sequestration of urban turfgrass systems in Hong Kong.
abstract: Climate change is more than just a global issue. Locally released carbon dioxide may lead to a rise in global ambient temperature and influence the surrounding climate. Urban greenery may mitigate this as they can remove carbon dioxide by storing carbon in substrates and vegetation. On the other hand, urban greenery systems which are under intense management and maintenance may contribute to the emission of carbon dioxide or other greenhouse gases. The impact of urban greenery on carbon balance in major metropolitan areas thus remains controversial. We investigated the carbon footprints of urban turf operation and maintenance by conducting a research questionnaire on different Hong Kong turfs in 2012, and showed that turf maintenance contributed 0.17 to 0.63 kg Ce m(-2)y(-1) to carbon emissions. We also determined the carbon storage of turfs at 0.05 to 0.21 kg C m(-2) for aboveground grass biomass and 1.26 to 4.89 kg C m(-2) for soils (to 15 cm depth). We estimated that the carbon sink capacity of turfs could be offset by carbon emissions in 5-24 years under current management patterns, shifting from carbon sink to carbon source. Our study suggested that maintenance management played a key role in the carbon budget and footprint of urban greeneries. The environmental impact of turfgrass systems can be optimized by shifting away from empirically designed maintenance schedules towards rational ones based on carbon sink and emission principles.
authors.affiliation: School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Kong
authors.affiliation: Shenzhen Key Laboratory of Southern Subtropical Plant Diversity, Fairy Lake Botanical Garden, Shenzhen & Chinese Academy of Science, Shenzhen, China.
authors.forename: Zhengjun
authors.initials: Z
authors.lastname: Shi
authors.affiliation: School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China. Electronic address: leemanchu@cuhk.edu.hk.
authors.forename: L M
authors.initials: LM
authors.lastname: Chu
mesh_terms: D000397:Air Pollution / Q000032:analysis / Q000517:prevention & control* / Q000706:statistics & numerical data; D002244:Carbon / Q000032:analysis; D002245:Carbon Dioxide / Q000032:analysis; D058572:Carbon Footprint; D057965:Carbon Sequestration; D003247:Conservation of Natural Resources / Q000379:methods*; D004784:Environmental Monitoring; D017752:Greenhouse Effect; D006723:Hong Kong; D006109:Poaceae; D012987:Soil
chemical_list: D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon
keywords: Carbon balance; Maintenance management; Soil; Turfgrass; Urban greenery