乌梁素海湖泊湿地植物区甲烷排放规律

运用静态箱法,对内蒙古乌梁素海不同水位的芦苇群落（Phragmites australis）和龙须眼子菜群落（Potamogeton pectinatus）的甲烷排放通量进行2 a（2003～2004）野外观测.发现龙须眼子菜群落（沉水植物）甲烷平均排放速率为(3.44±1.60) mg·(m²·h)^-1, 仅为芦苇群落（挺水植物）的平均排放速率的21.94%.高水位芦苇的排放速率要大于低水位芦苇群落.芦苇群落的甲烷排放具有明显的季节性和日变化规律,并且5 cm土壤温度和光合有效辐射分别是影响季节性和日变化的主要环境因子.根据观测数据和植物的分布面积,计算得出乌梁素海2003和2004年的甲烷排放量为1 024.6　t和1 156.7　t.

Methane Emission from Aquatic Vegetation Zones of Wuliangsu Lake, Inner Mongolia

To quantify the variations of methane fluxes from different aquatic vegetation zones, two-year measurements were measured at different aquatic vegetation zones and water depths using static chamber technique during two growing season from April to October in 2003 and 2004. Results showed that the average emission flux of CH4 from Potamogeton pectinatus (submerged macrophyte) growing zones was (3.44 +/- 1.60) mg x (m2 x h)(-1), 78.06% lower than that from Phragmites australis (emergent macrophyte). Significant seasonal and diurnal variations of CH4 emission were observed for Phragmites community; however, the variations were minor for P. pectinatus. Sediment temperature at 5 cm and photosynthesis active radiation were important factors influencing seasonal and diurnal variations of CH4 fluxes from Phragmites zone. Annual methane flux from the lake was 1 024.6 t and 1 156.7 t in 2003 and 2004, respectively.