title: [Short-term effects of fire disturbance on greenhouse gases emission from Betula platyphylla-forested wetland in Xiaoxing'an Mountains, Northeast China].
abstract: By the methods of static chamber and gas chromatography, this paper studied the effects of fire disturbance on the seasonal dynamics and source/sink functions of CH4, CO2 and N2O emissions from Betula platyphylla-forested wetland as well as their relations with environmental factors in Xiaoxing' an Mountains of China. In growth season, slight fire disturbance on the wetland induced an increase of air temperature and ground surface temperature by 1.8-3.9 degrees C and a decrease of water table by 6.3 cm; while heavy fire disturbance led to an increase of air temperature and 0-40 cm soil temperature by 1.4-3.8 degrees C and a decrease of water table by 33.9 cm. Under slight or no fire disturbance, the CH4 was absorbed by the wetland soil in spring but emitted in summer and autumn; under heavy fire disturbance, the CH4 was absorbed in spring and summer but emitted in autumn. The CO2 flux had a seasonal variation of summer > spring = autumn under no fire disturbance, but of summer > autumn > spring under fire disturbance; and the N2O flux varied in the order of spring > summer > autumn under no fire disturbance, but of autumn > spring > summer under slight fire disturbance, and of summer > spring = autumn under heavy fire disturbance. At unburned site, the CO2 flux was significantly positively correlated with air temperature and ground surface temperature; at slightly burned site, the CO2 flux had significant positive correlations with air temperature, 5-10 cm soil temperature, and water table; at heavily burned sites, there was a significant positive correlation between CO2 flux and 5-40 cm soil temperature. Fire disturbance made the CH4 emission increased by 169.5% at lightly burned site or turned into weak CH4 sink at heavily burned site, and made the CO2 and N2O emissions and the global warming potential (GWP) at burned sites decreased by 21.2% -34.7%, 65.6% -95.8%, and 22.9% -36.6% respectively, compared with those at unburned site. Therefore, fire disturbance could decrease the greenhouse gases emission from Betula platyphylla-forested wetland, and planned firing could be properly implemented in wetland management.
authors.affiliation: College of Forestry, Northeast Forestry University, Harbin 150040, China. mccnefu@yahoo.com
authors.forename: Chang-cheng
authors.initials: CC
authors.lastname: Mu
authors.forename: Bo-wen
authors.initials: BW
authors.lastname: Zhang
authors.forename: Li-dong
authors.initials: LD
authors.lastname: Han
authors.forename: Li-li
authors.initials: LL
authors.lastname: Yu
authors.forename: Han
authors.initials: H
authors.lastname: Gu
mesh_terms: D029662:Betula / Q000254:growth & development*; D002245:Carbon Dioxide / Q000032:analysis*; D002681:China; D017753:Ecosystem; D004784:Environmental Monitoring; D005390:Fires; D017752:Greenhouse Effect; D008697:Methane / Q000032:analysis*; D009609:Nitrous Oxide / Q000032:analysis; D012621:Seasons; D053833:Wetlands
chemical_list: D002245:Carbon Dioxide; D009609:Nitrous Oxide; D008697:Methane