闽江口不同沼泽植被带土壤甲烷产生潜力的温度敏感性

Temperature sensitivity of soil methane production potential in different marsh vegetation zones in the Min River estuary

2012年2月采集闽江河口鳝鱼滩短叶茳芏（Cyperus malaccensis）,芦苇（Phragmites australis）和互花米草（Scirpus alterniflora）3个典型潮汐沼泽植被带0∽30cm（间隔5cm）土壤样品,在不同温度（10,20和30℃）进行15d室内厌氧培养实验,探讨河口区不同沼泽植被带土壤甲烷产生潜力及其温度敏感性（Q10值）的特征.结果表明,指数模型较好地拟合不同沼泽植被带土壤甲烷产生与温度的相关关系;温度由10℃升至20℃时,3个沼泽植被带土壤甲烷产生潜力Q10值的均值分别为5.04,14.92和14.81,最大值均在培养期间的第13∽15d分别出现于10∽15cm,15∽20cm和20∽25cm三个土层;温度由20℃升至30℃时,3个沼泽植被带土壤甲烷产生潜力Q10值的均值分别为3.56,4.99和3.43,最大值分别在培养期间的第4∽6d,第4∽6d和第7∽9d出现于0∽5cm,0∽5cm和15∽20cm三个土层;植被类型和土壤深度对甲烷产生潜力及Q10值均具有显著的影响（P〈0.05）.

Quantifying response of soil methane production potential to temperature change in different wetland vegetation are vital to accurately evaluate effect of climate change on wetland ecosystem carbon balance. Soil samples at a depth of 0∽30cm（5cm interval） from three typical tidal marsh ecosystems dominated by Cyperus malaccensis, Phragmites australis and Spartina alterniflora, respectively, in the Min River estuary were collected in February 2012, and soil methane production potentials were determined using anaerobic incubation method. The results showed that there is an exponential correlation between methane production potential and soil temperature. The averaged Q10 value of three marsh vegetation zones were 5.04, 14.92, 14.81, and 3.56, 4.99, 3.43, respectively, with temperature rasing from 10 to 20℃ and from 20 to 30℃. Vegetation type, incubation temperature and soil depth had significant effects on the methane production potential and Q10 value（P0.05）.