火干扰对小兴安岭毛赤杨沼泽温室气体排放动态影响及其影响因素  

Dynamics of greenhouse gases emission and its impact factors by fire disturbance from Alnus sibirica forested wetland in Xiaoxing′an Mountains,Northeast China

作　　者：顾韩[1,2] 牟长城[1] 张博文 

机构地区：[1]东北林业大学林学院,哈尔滨150040 [2]黑龙江科技学院,哈尔滨150027 [3]佳木斯市环境科学院,佳木斯150042

出　　处：《生态学报》2012年第24期7808-7817,共10页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(30670349)

摘　　要：利用静态箱-气相色谱法,对小兴安岭轻度火烧毛赤杨沼泽CH4、CO2、N2O生长季排放通量进行研究。结果表明:火烧使毛赤杨沼泽生长季CH4排放通量提高485.2%,CO2和N2O排放通量分别下降45.5%、24.8%。火烧未改变CH4季节性排放规律,但改变了CO2、N2O季节性变化规律。火烧样地CH4排放通量与土壤15cm温度间存在显著正相关性关系而与水位相关性不显著,火烧样地CO2排放与土壤0—30 cm温度呈显著或极显著正相关,与水位极显著负相关。对照样地CO2排放通量与土壤0—15 cm温度呈显著或极显著正相关,与水位极显著负相关,火烧使毛赤杨沼泽CH4排放源的强度增强,CO2、N2O的排放消弱,全球温室潜势下降约为43.34%。Wetlands are important sources and sinks of greenhouse gases. Fire disturbance plays an important role in wetland ecosystems, it commonly is a important carbon sink of the land ecosystems, the Lesser xing＇an Mountains of China＇ s northeast is the frequent area of the fire disturbance as well as a major distribution area of China＇s wetlands. Fire-related disturbance in forests are more frequent in mid-to high latitudes than elsewhere. In the present study, Alnus sibirica wetland, were studied to reveal the emission variation of CH4, CO2, and N2O under fire disturbance during the growing season. The study area is located in the Lesser Xing＇ an Mountains. We used a static opaque chamber and gas chromatography methods, and we monitored related environmental factors. The results were as follows： disturbance by fire increased air and soil temperature by 2.5--5.0℃, and lowered the water table by an average of 0.24--6.36 cm. Burning increased CH4 emissions from Alnus sibirica wetlands by 485.2. Burning decreased the CO2 and N2O emissions by 45.5% and 24.8% respectively from Alnus sibirica wetland. Burning also changed the Alnus sibirica wetland CO2 and N2O flux patterns in the growing season, but no marked variations were detected in the Alnus sibirica wetland CH4. Burning changed the Alnus sibirica wetland green-house gas flux patterns in the growing season. The CH4 emissions and the seasonal change pattern were affected by fire disturbance. Before and after the fire disturbance, CH4 emission flux remained unchanged during the growing season. The CH4 was absorbed weakly by the wetland soil（ M0 ,M1 ） in spring and emitted in summer and autumn. The CH4 emission flux in summer was less than that in autumn, the CO2 and N2O emission fluxes had changed. At the unburned site, the CO2 flux had a seasonal variation where summer flux 〉 spring 〉 autumn; under fire disturbance, the CO2 flux in summer 〉 autumn〉 spring. The N2O flux varied in the order of spring 〉 autumn 〉 summer under no fire disturbance,

关 键 词：小兴安岭 毛赤杨沼泽 温室气体排放 火干扰 

分 类 号：X502[环境科学与工程—环境工程]