胶州湾潮滩湿地CHBr_3通量特征及影响因素研究

CHBr_3 fluxes and controlling factors in tidal flat wetland of Jiaozhou Bay

在2016年7月~2017年5月期间,运用静态箱法对胶州湾潮滩湿地系统的CHBr_3排放通量进行了观测,并对影响CHBr_3通量的主要影响因子进行了探究.结果表明,胶州湾潮滩湿地是CHBr_3的排放源,互花米草湿地和光滩释放CHBr_3的通量均值分别为10.92nmol/(m^2?d)和8.96nmol/(m^2?d),说明互花米草湿地在一定程度上能够促进CHBr_3的排放.不同潮滩湿地之间CHBr_3的排放通量有明显区别.互花米草湿地在夏秋季节较高的CHBr_3通量可能主要是受温度和植被生物量的影响,光滩在冬春季节较高的CHBr_3通量可能与冻融循环过程有关.胶州湾潮滩湿地环境因素变化比较复杂,CHBr_3的排放通量受多种因素的影响.温度对CHBr_3排放通量的影响显著,而植被生长状况、水盐条件和营养元素等对CHBr_3排放通量的影响也不容忽视.

Characteristics of methenyl bromide(CHBr3)fluxes from tidal wetlands of the Jiaozhou Bay were observed using static flux chambers methods during 2016/2017,and the key factors affecting CHBr3 fluxes were discussed.The results showed that CHBr3 average fluxes from S.alterniflora marsh and bare flat marsh were 10.92nmol/(m^2.d)and 8.96nmol/(m^2.d),respectively,indicating that the tidal marsh ecosystems in the Jiaozhou Bay acted as CHBr3 source.It indicates that S.alterniflora marshes could promote CHBr3 emissions to some extent.The emission fluxes of CHBr3 between different tidal marshes was distinctly different.The higher CHBr3 emissions from the S.alterniflora marshes were occurred in summer and autumn were probably related to the effects of temperature and vegetation biomass.The higher fluxes of CHBr3 in bare flat during early spring and winter may be related to the freeze-thaw cycle.The change of environmental factors in the tidal flat marsh of Jiaozhou Bay was complex,and the emission fluxes of CHBr3 were affected by many factors.The dominant factor affected the CHBr3 emission in S.alterniflora marsh of Jiaozhou Bay was temperature,while the influences of vegetation growth status and water and salinity condition and nutrient elements on the CHBr3 fluxes characteristics might not be ignored.