水位对巴音布鲁克天鹅湖高寒湿地土壤呼吸的影响

Effect of water level on the soil respiration in a Swan Lake Wetland at Bayanbulak

以新疆维吾尔自治区天山中部巴音布鲁克天鹅湖高寒湿地为研究区域,结合室内水位控制试验,初探土壤水位对土壤呼吸的影响,结果表明:1)土壤呼吸与土壤水位呈现显著的负相关性(r=-0.997;p=0.003),5cm、0cm、-10cm、-20cm水位梯度下土壤呼吸速率平均值分别为1.27、2.49、4.60、6.21μmol·m^(-2)·s^(-1)。2)不同水位处理下土壤碳排放量差异性达到极显著水平(p<0.01),5cm、0cm、-10cm、-20cm水位条件下土壤碳排放量分别为0.11、0.22、0.40、0.54mol·m^(-2)·d^(-1)。3)不同水位条件下土壤呼吸速率与5cm土壤温度均表现为显著正相关关系,淹水条件下水温与土壤呼吸速率表现为显著正相关性,且随着土壤水位的下降水温与土壤呼吸的相关性系数减弱。各水位梯度土壤呼吸速率与5cm土壤温度均呈显著的指数函数关系,水位降低显著提高了土壤呼吸温度敏感性系数(Q10)(p<0.05)。

Taking the Bayanbulak Swan lake alpine wetland which was located in the center of Tianshan Mountain in Xinjiang Uygur Autonomous Region as the study area, combined with the indoor water level control experiment, we preliminary studied the effect of soil water level on soil respiration. The results showed that： （ 1 ） There was a significant positive correlation between the soil respiration and soil water level （ r = - 0.997 ; p = 0. 003）, 5cm, 0cm, -10cm, -20cm water level gradient in soil respiration rate were respectively 1. 27, 2.49, 4.60, 6.21 μmol · m^-2 · s^- 1 （2） The soil carbon emissions had a significant difference （P 〈 0.01 ） compared with the soil carbon emissions in different water level. Soil carbon emissions at 5cm, 0cm, - 10cm and - 20cm were 0.11,0.22, 0.40 and 0.54mol · m^-2· d^-1 respectively. （3） Under different water level conditions, soil respiration rate and 5cm soil temperature showed significant positive correlation. Under the condition of waterlogged, water temperature and soil respiration rate showed significant positive correlation, and with the dropping of soil water level, the correlation coefficient of water temperature and soil respiration decreased. The soil respiration rate in the water level gradients and the 5cm soil temperature showed a significant exponential function. The temperature sensitivity （Q10） （p 〈0.05 ） of soil respiration increased by reduced water table.