为探索湿地水位变化与土壤气体排放之间的关系,对黄河中游芦苇湿地进行了半注水和满注水样地处理后的动态监测,对比了7 d水位变化过程中土壤气体排放差异。结果表明：注水造成了土壤CO₂排放速率的显著差异;随土壤温度上升,H₂O、CO₂、H₂S排放速率都有上升趋势（满注水样地的H₂O除外）;半注水和满注水造成的影响,H₂O排放速率表现为趋同-异步-消失的特征,在注水前期（63.73 h）半注水和满注水差异基本一致,后期差异较大,直至125.64 h后注水的影响才消失,总体分别造成H₂O排放总量76.3%和31.3%的增加;CO₂排放速率表现为异步-趋同的特征,注水初期环境的改变造成CO₂排放的一致减少,37.69~68.66 h二者出现明显差异,68.66~125.64 h水位虽然恢复,但差异仍然存在,注水分别造成CO₂排放总量50.1%和43.2%的减少;H₂S排放速率表现为无变化-异步-无变化的特征,总体造成H₂S排放总量42.3%和32.3%的增加。研究追踪了水位上升后土壤H₂O、CO₂和H₂S排放速率变化的动态过程,其影响具有异步性和持续性的特点,CO₂排放速率表现出较长的响应周期。研究结果对于河流湿地生态功能研究具有重要意义,湿地土壤气体排放对水位变化的响应滞后意味着对湿地生态功能的重要影响,其波动过程需要更长时段的精准研究。

Wetlands have an ecological purpose that is correlated with global climate change. On the background of climate change, the spatial and temporal variations of global precipitation amplify the effect on the water environment of river wetlands via catchment confluence, affecting the ecological function of wetlands significantly. To examine the relationship between wetland water level changes and soil gas emission, half water injection and full water injection treatments were considered in reed wetlands in the middle reaches of the Yellow River in China, and the differences in soil gas emission during the 7-day monitored were compared. Compared with natural sites, water injection created a significant difference in soil CO₂ emission rate. Except for the H₂O emission rate of full water injection, H₂O, CO₂, and H₂S emission rates all considered upward trend with soil temperature rising. In the monitoring process, for the effect of half and full water injection, H₂O emissions rate half and full water injection were basically the same, while the difference was higher in the later stage, the effect of did not disappear until 125.64 h, totally water injection resulted in an increase of 76.3% and 31.3% respectively; CO₂ emissions rate appeared asynchronous-converging characteristics, the changes of environment in the initial stage resulted in the consistent reduction of CO₂ emission, and considered a significant difference between 37.69 h and 68.66 h, although the water level recovered from 68.66 h to 125.64 h, the differences still existed, water injection resulted in a reduction of CO₂ total emissions by 50.1% and 43.2% respectively. H₂S emissions rate experienced changeless-asynchronous-changeless process, and totally, resulted in 42.3% and 32.3% increase. The study tracked the dynamic process of soil H₂O, CO₂, and H₂S emission rates after water level rise and found that the effect of a rise of water level on the soil gas emission rate was asynchronous and persistent, demonstrating a long response cycle to CO₂ emissions rate. The results consider high significance to the ecological function of river wetlands, the delayed response of wetland soil gas emission to water level change means that it has a significant effect on wetland ecological function, its fluctuation process needs a longer period of accurate study.