滨海湿地实验室知识库

中国科学院烟台海岸带研究所海岸带环境过程重点实验室山东省海岸带环境过程重点实验室; 中国科学院研究生院; 中国科学院东北地理与农业生态研究所;  

2009年秋季(9、10月),运用静态暗箱-气相色谱法对黄河口滨岸潮滩湿地系统的CH4排放通量进行了观测,并对影响CH4通量特征的关键因子进行了识别.结果表明,在空间上,秋季高潮滩、中潮滩、低潮滩和光滩的CH4通量范围分别为-0.206～1.264、-0.197～0.431、-0.125～0.659、-0.742～1.767 mg.(m2.h)-1,均值为0.089、0.038、0.197和0.169mg.(m2.h)-1,均表现为CH4排放源,但源功能整体表现为低潮滩>光滩>高潮滩>中潮滩; 在时间上,9、10月的CH4排放通量范围分别为-0.444～1.767、-0.742～1.264 mg.(m2.h)-1,均值为0.218、0.028 mg.(m2.h)-1,除9月高潮滩表现为CH4弱汇外,其它潮滩的CH4通量均明显高于10月.研究发现,黄河口滨岸潮滩湿地环境因素变化比较复杂,CH4排放通量受多重因素控制.不同潮滩湿地在9、10月CH4排放通量的差异可能主要与温度(特别是气温)以及植被生长状况的差异有关,而水盐条件和潮汐状况对潮滩湿地系统CH4通量特征的影响也不容忽视.  

The characteristics of methane (CH4) fluxes from tidal wetlands of the Yellow River estuary were observed in situ with static-chamber and GC methods in September and October 2009，and the key factors affecting CH4 fluxes were discussed．From the aspect of space，the CH4 flux ranges in high tidal wetland，middle tidal wetland，low tidal wetland，bare flat are -0. 206-1. 264，-0.197-0.431，-0.125-0. 659 and-0.742-1.767mg·( m2·h)-1，the day average fluxes are 0.089，0.038，0.197 and 0.169 mg·(m2·h)-1，respectively，indicating that the tidal wetlands are the sources of CH4 and the source function of CH4 differed among the four study sites，in the order of low tidal wetland＞bare flat ＞ high tidal wetland＞middle tidal wetland．From the aspect of time，the ranges of CH4 fluxes from the tidal wetland ecosystems are-0. 444-1.767 and -0. 742-1. 264 mg·( m2·h)-1 ，and the day average fluxes are 0.218 and 0. 028mg·(m2·h)-1 in September and October，respectively．The CH4 fluxes in each tidal wetland in September are higher than those in October except that the high tidal wetland acts as weak sink in September．Further studies indicate that the changes of environmental factors in the Yellow River estuary are complicated，and the CH4 fluxes are affected by multiple factors．The differences of CH4 fluxes characteristics among different tidal wetlands in autumn are probably related to temperature (especially atmospheric temperature) and vegetation growth status，while the effects of water or salinity condition and tide status on the CH4 flux characteristics might not be ignored．