杭州西溪湿地CH_4、CO_2通量及其主要影响因子

Fluxes and Influencing Factors of CO_2 and CH_4 in Hangzhou Xixi Wetland,China

本研究采用便携式温室气体分析仪连接通量箱在线监测杭州西溪湿地CH_4、CO_2通量日变化及季节变化,同时也对包括有机碳含量、湿度、孔隙度、比重、p H、Eh在内的潜在影响因子进行了研究。结果表明,通常情况下,CH_4、CO_2通量的变化分别为-0.001 9~0.035 3mg/(m^2·h)和-109.76~442.55mg/(m^2·h);CH_4、CO_2通量的变化存在明显正相关关系。CH_4通量的季节变化表现为夏季>秋季>春季>冬季;CO_2通量的季节变化表现为夏季>春季>冬季>秋季。土壤湿度是影响CH_4通量变化的重要因子,通常湿度越大,CH_4通量越大;在生长季维管植物有助于CH_4的氧化;西溪湿地土质差异也使CH_4、CO_2通量排放有所差异,具体表现在土壤有机碳含量相差较大,而土壤中有机碳的含量与CH_4产生潜力呈显著正相关。

The study was target on detecting seasonal dynamics of CH4 and CO2fluxes and their potential impact factors to Hangzhou Xixi Wetland,China. Content of TOC,humidity,porosity,specific gravity,p H,and Eh of soil samples were also detected. Results show that the fluxes of CH4 emissions varies from-0. 001 9 - 0. 035 3 mg/（ m^2·h）; the fluxes of CO2 emissions varies from-0. 001 9 -0. 035 3 mg/（ m^2·h）. The seasonal vibration of CH4 fluxes is according the order of summer〉autumn〉spring〉winter; and the seasonal vibration of CO2 fluxes is as the order of summer〉spring〉winter〉autumn. There is an extraordinary positively relationship between the flux of CH4 and CO2emissions. Soil moisture is an important factor affecting the CH4 flux,and CH4 fluxes increase with increasing moisture. Vascular plants play a more important role in the consumption of CH4,during the growing stage. The difference of soil in Xixi Wetland lead to the large difference of the CH4 flux,specifically in content of TOC,which has significant positive relationship with the CH4 emissions.