中文摘要：

水库近岸湿地（消落区）温室气体（CO2、CH4）产汇是水库温室气体效应问题的重要组成部分.本文以三峡水库支流澎溪河的白家溪、养鹿两处大面积消落区为研究对象,于2010年6-9月水库低水位运行期间,对近岸消落区土-气界面CO2、CH4通量进行监测.白家溪消落区土-气界面CO2通量均值为12.38±2.42 mmol/（m2·h）；CH4通量均值为0.0112±0.0064 mmol/（m2·h）.养鹿消落区CO2、CH4通量均值分别为10.54±5.17、0.14±0.16 mmol/（m2·h）.总体上,6-9月土-气界面CO2通量呈增加趋势,而CH4通量水平呈现显著的递减趋势.消落区土地出露后植被恢复,在一定程度上促进了土壤有机质含量的增加,使得6-9月CO2释放通量的总体趋势有所增加.消落区退耕后,其甲烷氧化菌的活性得到恢复,加之在土地出露曝晒过程中土壤透气性增强,使得消落区土壤对大气中CH4吸收氧化潜势增强.尽管如此,仍需进一步的研究以明晰消落区土气界面CO2、CH4产汇的主要影响因素.

英文摘要：

The CO2 and CH4 fluxes on wetland （ water level drawdown） area of reservoirs are crucial parts of the scientific research of reservoir Green House Gas emission. CO2 and CH4 fluxes at soil-water interface of Baijiaxi and Yanglu drawdown areas in the Pengxi River were studied from June to September in 2010. Baijiaxi drawdown area has a mean CO2 flux of 12.38 ±2.42 mmol/ （ m2 · h） , while its mean CH4 flux is 0.0112. ±0. 0064 mmol/（ m2 , h）. The mean fluxes of CO2 and CH4 at soil-air interface in Yanglu drawdown area are 10.54 ± 5.17 mmol/（ m2 · h） and 0.14 ± 0.16 mmoL/（ m2 · h） , respectively. A significant increase of CO2 flux and a comparable decrease of CH4 during the study period have been observed. Recovery of the vegetation and an in- crease in soil organic matter contents are generally regarded as the primary reason for the increase of CO2 flux. Loss of water in soils during the period increases the intensities of oxygen transfer from air to soils, which could help to increase the activities of metha- notrophic bacteria, and to increase the capability of CH4 sink in the drawdown zone. However, it is suggested that further study should be taken on elucidating the co-effect of COEand CH4 fluxes by the reservoir operation and land-use history in this area.