三江平原湿地CH_4、N_2O的地-气交换特征  

Characteristics of CH_4,N_2O exchange between wetland and atmosphere in the Sanjiang Plain

作　　者：王毅勇[1] 郑循华[2] 宋长春 赵志春[1] 

机构地区：[1]中国科学院东北地理与农业生态研究所,长春130012 [2]中国科学院大气物理研究所LAPC开放实验室,北京100029

出　　处：《地理研究》2006年第3期457-467,共11页Geographical Research

基　　金：国家自然科学基金重点项目(编号40331014);中国科学院资源环境领域野外台站研究基金;中国科学院东北地理与农业生态研究所湿地生态与环境重点实验室基金项目(WELF-2004-B-004)资助

摘　　要：利用暗箱-气相色谱法对三江平原3种具有代表性的湿地类型（常年积水的毛果苔草沼泽、季节性积水的小叶章湿草甸和灌丛湿地）进行了为期两年的CH4和N2O现场同步观测.结果表明,湿地全年CH4和N2O通量有明显的季节和年际变化,与温度和土壤水分条件密切相关.在发生季节性干旱的年份,生长季（5月～10月）CH4排放通量峰值出现在6月和8月,呈双峰型;而在降水充沛的年份,CH4排放通量峰值出现在6、7月份,呈单峰型.冰冻期（11月到次年4月）CH4排放通量十分的微弱,其中灌丛湿地表现为负排放.3种类型湿地N2O通量一般在非冰冻期表现为排放,呈双峰型,5月份融化期为第一个高峰期,7、8月为第二个高峰期,冰雪覆盖期表现为吸收.湿地CH4和N2O通量在春季的融冻期,存在此消彼长的现象.Methane and nitrous oxide are the very important greenhouse gases. Although CH4 and N2O concentrations are considerably lower than that of CO2 in the atmosphere, however they are more effective on a molar basis than CO2 in resulting in radiative heating.Increasing CH4 and N2O concentrations in the atmosphere have stimulated studies on CH4 and N2O emissions from terrestrial and aquatic environments. Wetlands are regarded as one of the major sources of CH4, about 21% of global methane emission come from natural wetlands. The Sanjiang plain, the largest and most concentrated marsh-wetland region in China, is located in the northeast of Heilongjiang province. Its total marsh-wetland area is about 83.5× 10^4 hm^2with rich carbon resources. There are many rivers and lakes in this region and wide flood plain were formed along the river. The study was carried out at the Ecological Experimental Station of Mire-Wetland in the Sanjiang Plain, Chinese Academy of Sciences （47°35′ N, 133°31′ E; 56 m above sea level）, center of the Sanjiang plain. The mean annual precipitation is 550-600 mm and the mean annual temperature 1.9 ℃. The vegetation types are marshes and wet meadows. The main soil types are marsh soil, meadow soil and lessive soil. Three typical types of wetlands of perennial waterlogged Carex lasiocarpa marsh, seasonal waterlogged Deyeuxia angustifolia wet meadow and perennial non waterlogged brushy wetland are selected as samples of study. The methane and nitrous oxide fluxes were measured by sealed stainless steel chamber and gas chromatography（Agilentilent 4890） system. The experiment lasted from June 2002 to August 2004, measurement was done twice a week in growth season, once a month in winter, and daily change observation was performed several times at the clear day during growth season and three repeats were practised at each sample site. Meanwhile, the inside and outside chamber air temperature, surface and 5 cm deep soil temperature were measured at the same time. The two year＇s experi

关 键 词：三江平原 典型湿地 CH4、N2O通量 

分 类 号：X37[环境科学与工程—环境工程]