Li Jun, Ma Liang, Zhang Boxin, Zou Yuncan, Wang Hanxi, Zang Shuying
Heilongjiang Province Key Laboratory of Geographical Environment Monitoring and Spatial Information Service in Cold Regions / School of Geographical Sciences, Harbin Normal University, Harbin, 150025, China.
Heilongjiang Province Key Laboratory of Geographical Environment Monitoring and Spatial Information Service in Cold Regions / School of Geographical Sciences, Harbin Normal University, Harbin, 150025, China; Heilongjiang Province Collaborative Innovation Center of Cold Region Ecological Safety, Harbin, 150025, China.
J Environ Manage. 2025 Apr;380:125178. doi: 10.1016/j.jenvman.2025.125178. Epub 2025 Mar 31.
The alterations in climatic conditions have led to soil drying-rewetting (DRW) events in permafrost regions, which result in heightened emissions of greenhouse gas (GHG). However, there is currently a lack of comprehensive research on GHG emissions from permafrost under the DRW conditions. To reveal the changes of GHG emissions in permafrost, laboratory simulation experiments were conducted on 0-60 cm active layer soil in four soil ecosystems (Larix gmelinii, Betula platyphylla, mix of L. gmelinii and B. platyphylla, peatland) of the Daxing'an Mountains, northeast China. A 210-day soil cultivation experiment was conducted to investigate the effects of DRW on soil physicochemical properties and GHG emissions. The research showed that all soils exhibited emission sources of carbon dioxide (CO) and nitrous oxide (NO). The mean fluxes of CO, NO, and CH in peatlands with DRW were 520.33 ± 374.24 mg m h, 167.96 ± 112.24 μg m h, and 1.02 ± 2.84 μg m h, respectively. Mean CO flux from peat soil increased by 2.10 times with DRW, and mean NO flux increased by 1.74 times for the soil of B. platyphylla. CO and NO emissions exhibited variability during DRW. CH emissions were lower under the soil DRW compared to constant moisture treatment. The influence of these alternating conditions on soil GHG fluxes was substantial at 25 °C. The DRW conditions had no significant effect on CH in three types of forest soils. This study offers valuable insights for accurately predicting the impact of climate warming on changes in permafrost soil.
气候条件的变化导致了多年冻土区土壤的干湿交替事件，这导致温室气体（GHG）排放增加。然而，目前对于干湿交替条件下多年冻土温室气体排放缺乏全面研究。为了揭示多年冻土中温室气体排放的变化，在中国东北大兴安岭的四个土壤生态系统（兴安落叶松林、白桦林、兴安落叶松与白桦混交林、泥炭地）的0-60厘米活动层土壤上进行了实验室模拟实验。进行了为期210天的土壤培养实验，以研究干湿交替对土壤理化性质和温室气体排放的影响。研究表明，所有土壤均表现出二氧化碳（CO）和一氧化二氮（NO）的排放源。干湿交替条件下泥炭地的CO、NO和CH的平均通量分别为520.33±374.24毫克·米-2·小时-1、167.96±112.24微克·米-2·小时-1和1.02±2.84微克·米-2·小时-1。泥炭土的平均CO通量在干湿交替时增加了2.10倍，白桦林土壤的平均NO通量增加了1.74倍。在干湿交替期间，CO和NO排放表现出变异性。与恒定湿度处理相比，土壤干湿交替条件下CH排放较低。在25℃时，这些交替条件对土壤温室气体通量的影响很大。干湿交替条件对三种森林土壤中的CH没有显著影响。本研究为准确预测气候变暖对多年冻土土壤变化的影响提供了有价值的见解。
