“黑土型”退化高寒草地CH_4排放特征研究

Research of CH_4 Emission Characteristics of 'Black Soil Patch' Degraded Alpine Meadow

[目的]研究"黑土型"退化高寒草地CH4的排放特征。[方法]采用静态箱-气相色谱法研究了青海省果洛州"黑土型"退化高寒草地植被-土壤系统CH4释放特征。[结果]"黑土型"退化高寒草地不同处理(植被-土壤、土壤和土壤微生物)CH4释放速率的日变化动态不明显,绝大部分时间处于吸收CH4状态。"黑土型"退化高寒草地不同处理CH4释放速率的季节动态也不明显,且绝大部分时间处于吸收状态;在观测期间,释放速率为:植物-土壤>土壤>土壤微生物,平均值为-(28±26)、-(38±21)和-(43±25)μg/(m2.h)。"黑土型"退化高寒草地植物及地上、地下部分CH4释放速率的季节动态变化不显著;在观测期间,除个别观测日外,三者均表现为正排放,释放速率为:植物体>地上部分>地下部分。[结论]明确了青藏高原地区"黑土型"退化高寒草地CH4释放速率的特征,为将来退化高寒草地的治理、恢复、重建提供了科学依据。

[ Objective ] The research aimed to study the CH4 emission characteristics of ＇ Black soil patch＇ degraded alpine meadow. [ Method] The static chamber-gas chromatographic techniques was used to study the CH4 emission characteristics of vegetation-soil system of Black soil patch＇ degraded alpine meadow in Guoluo Zhou, Qinghai Province. [ Result] The results showed that the diurnal variation ofCH4 emission rates of different treatments（ vegetationsoil, soil and soil microorganism） in ＇ Black soil patch＇ degraded alpine meadow was not obvious, and the most time were being in the state of absorbing CH4. The seasonal variation of CH4 emission rates of different treatments（ vegetation- soil, soil and soil microorganism） in ＇ Black soil patch＇ degraded alpine meadow were also not obvious, the most time were being in the state of absorbing CH4, and during observation the emission rates were in the order： Vegetationsoil 〉 soil 〉 soil microorganism, the average value was - （28 ±26）, - （38 ± 21 ）, - （43 ±25 ）μg/（ m2 · h） respectively. The seasonal variation of CH4 emission rates from plants, overground part of plants and underground part of plants in ＇ Black soil patch＇ degraded alpine meadow was not obvious, and during observation the emission rate was all positive. The size order was： Plants 〉 overground part of plants 〉 underground part of plants. [ Conclusion] The study confirmed the CH4 emission characteristics of ＇ Black soil patch＇ degraded alpine meadow in Tibet plateau area, and provided the scientific basis for controlling, restoring and reconstructing degraded alpine meadow in future.