An undisturbed sediment column sample covered by Shichito matgrass (Cyperus malaccensis) in the Shanyutan and Daoqingzhou wetland of the Min River estuary was selected to research the effects of salinity on the denitrification process of the wetland sediment in July 2015.Using the sealed anaerobic culture method,the denitrification rates,which varied with the culture time in different salinity conditions,were calculated.At the initial stage,from low salinity to high salinity culture conditions,the denitrification rates of the sediments in the Shanyutan wetland were (15.5±1.38),(4.28± 8.46),and (12.94±0.24) mg kg-1 d-1,respectively.The values in the Daoqingzhou wetland,however,were (31.93± 4.89),(30.66±5.375) and (36.69±3.44) mg kg-1 d 1,respectively.The decreased amplitudes of the denitrification rates after 10 days in 0 and 10 salinity conditions were 36.97％,and 53.01％,respectively,of the amplitudes after 5 days.The values were higher compared with 22.64％ and 28.84％ in the Daoqingzhou wetland.In the late culture stage,the denitrification rates showed decreasing trends down to zero.The denitrification activities in the Shanyutan and Daoqingzhou wetlands both showed trends of increasing.The variation ranges in the Shanyutan and and Daoqingzhou wetland were 95.6％-99.8％ and 90.0％-96.7％,respectively.During the entire training period,the denitrifying activity in the Shanyutan wetland was higher than that in the Daoqingzhou wetland.The results reflected that the salinity had an inhibition effect on the denitrification rate of the sediment in the Min River estuary wetland.%为了探讨河口区湿地沉积物反硝化强度对盐度的响应,2015年7月选择闽江河口覆盖短叶茳芏的鳝鱼滩和道庆洲湿地沉积物为研究对象,采用密封厌氧培养,计算不同培养时期在不同盐度下的反硝化速率.结果表明,在反硝化培养的初期,鳝鱼滩的反硝化速率从低盐度到高盐度分别为(15.5±1.38)、(4.28±8.46)、(12.94±0.24) mg kg-1 d-1,道庆洲分别为(31.93±4.89)、(30.66±5.375)、(36.69±3.44) mg kg-1d-1,鳝鱼滩的10天反硝化速率在0和10盐度下降幅度分别是5天的36.97％ 、53.01％,高于道庆洲22.64％、28.84％,后期随着时间的变化整体上呈现减小的趋势并趋于0.另外,鳝鱼滩和道庆洲反硝化活性随着时间呈现逐渐增加的趋势,其鳝鱼滩变化幅度在95.6％-99.8％,道庆洲为90.0％-96.7％,整个培养期间,鳝鱼滩的反硝化活性均高于道庆洲的反硝化活性.以上结果反映出盐度对闽江河口湿地沉积物的反硝化速率起到一定的抑制作用.
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