Abstract: Temperature is one of the most important environmental factors that affect the activity of microorganisms in the soil, and it is the main regulatory factor for the nitrification process of wetland soil. Taking Gannan Gahai Wetlands as the research object, 98 days indoor aerobic cultivation experiment was performed to determine the characteristics of soil nitrification process in four degrees of degradation wetland soils (non-degraded UD, slightly degraded LD, moderately degraded MD, and severely degraded HD) under different soil layers (0~10 cm, 10~20 cm and 20~40 cm) and different temperature(15℃, 25℃, 35℃). The results showed that:Under various temperature conditions, the soil nitrate nitrogen content increased first and then decreased with the extension of the cultivation time;increased with the increase of the wetland degradation gradient;The net nitrification rates increased with the increase of soil temperature in the 0~10 cm soil layer, but increased first and then decreased with the increase of soil temperature in the 10~20 cm and 20~40 cm soil layers. The Q₁₀ value(Multiple of increase in net nitrification rate per 10℃ increase in temperature) of the soils of the four degraded soil layers from 15℃ to 25℃ was higher than that of 25℃ to 35℃, indicating that the net nitrification of the soil was the most sensitive at 15℃ to 25℃. It can be seen that wetland degradation increases soil nitrification;while the increase of temperature promotes the process of soil nitrogen nitrification process.

Key words: Nitrification, Temperature, Gahai wetland

摘要： 温度是影响土壤中微生物活性最重要环境因素之一，是湿地土壤硝化过程的主要调控因子。以甘南尕海湿地为研究对象，通过室内98 d的好气培养，研究4种退化程度（未退化UD、轻度退化LD、中度退化MD及重度退化HD）湿地土壤在不同土层（0~10 cm，10~20 cm和20~40 cm）、温度（15℃，25℃，35℃）条件下的土壤硝化过程特征。结果表明：各温度条件下，土壤硝态氮含量随培养时间的延长先增加后减小，而随湿地退化程度的增加而增加；土壤净硝化速率在0～10 cm土层随温度的升高而增加，而在10～20 cm和20～40 cm土层随温度的升高呈先增加后减小趋势；4种退化程度各土层土壤15℃升高到25℃的Q₁₀值（温度每升高10℃土壤净硝化速率增加的倍数）高于25℃升高到35℃，说明土壤净硝化在15℃～25℃最敏感。综上所述，湿地退化增加了土壤硝化作用，同时温度升高促进了土壤氮硝化过程。

关键词: 硝化作用, 温度, 尕海湿地