Study On The Characteristics Of CO₂ And CH₄ Release And Its Influencing Factors In The Middle Section Of The Three Gorges Reservoir Area

Greenhouse gas emissions in the three Gorges Reservoir area have received much attention this year.In order to reveal the influencing factors of greenhouse gas emission in the middle section of the three Gorges Reservoir area,the main object of this study is the main stream of the Yangtze River in the middle part of the three Gorges Reservoir area,and the sampling sites are Fuling?Nantuo Town?,Zhong County?Shibaozhai?and Wanzhou?Xiaozhou Town?in the middle part of the three Gorges Reservoir area.The CO₂,CH₄ concentration and other environmental indexes in the middle section of the three Gorges Reservoir area were measured every 1 to 2 months,and the flux of CO₂,CH₄ was estimated.The characteristics of CO₂,CH₄ and other environmental indexes are analyzed,and the effects of different regions and three Gorges Reservoir area on the regulation and storage operation are expounded.The influence of CO₂,CH₄in the middle section of the three Gorges Reservoir area.The following main conclusions are obtained in this study:?1?Fuling,Zhongxian and Wanzhou water bodies all show the source of CO₂,Fuling,The water body of Zhongxian county is the source of CH₄,while the water body of Wanzhou is the sink of CH₄.?2?There was a significant positive correlation between TOC and TN in the middle part of the three Gorges Reservoir area.The increase of TOC represented the increase of organic matter and the increase of organic nitrogen in organic matter,so TN also increased,and the concentration of TOC and CO₂,CH₄ were significantly positively correlated.The DO in the water is affected by the regulation and storage operation of the three Gorges Reservoir area,and the velocity of flow has a great influence on the DO.Ammonia-nitrogen had no significant correlation with CO₂,CH₄ concentration,but nitrate-nitrogen was positively correlated with CO₂,CH₄,because nitrate-nitrogen was more easily bioavailable than ammonia-nitrogen,and the velocity of velocity was higher in the middle reaches of the Yangtze River in the middle of the three Gorges Reservoir area.Ammonia nitrogen is easily released from the water.?3?In space,there was no significant difference in the concentration of CO₂,CH₄ in different water depths,but there was no significant difference in the concentration of CO₂ in different areas,but there was significant difference in the concentration of CH4,and the effect of different regions on CH₄ was greater.?4?In terms of time,the regulation and storage operation of the three Gorges Reservoir has greatly affected the water CO₂,CH₄ and environmental indexes in the middle part of the three Gorges Reservoir area.During the whole sampling period,only CH₄ and pH in Fuling,Zhongxian and Wanzhou were significantly different.The CO₂,CH₄,TOC,ammonia nitrogen,nitrate nitrogen and pH of Fuling,Zhongxian and Wanzhou are significantly different from those of flood season,storage period,low water period and discharge period.Although there is no significant difference in some indexes in different regions during the whole sampling period,when the influence of regulating and storing operation in the three Gorges Reservoir area is added,the regional influence will also follow.Show it.