在春季洪水期间,来自下奥布河泛滥平原的碳排放
Sergey N Vorobyev1, Yuri Kolesnichenko1, Jan Karlsson2
1BIO-GEO-CLIM Laboratory, Tomsk State University, Tomsk, Russia.
The Science of the total environment
|September 16, 2024
概括
北极河流,特别是它们的洪水平原,是重要的碳来源. 泛滥平原湖泊和二次通道的二氧化碳排放量超过主要河流干,突出需要将高水位纳入全球碳排放评估.
科学领域:
- 环境科学 环境科学
- 气候科学 气候科学
- 地质化学 地质化学
背景情况:
- 北极河流在全球碳循环中发挥着至关重要的作用,作为气候变暖的积极反机制.
- 广泛的泛滥平原,临时水体和二次通道对北极河流中二氧化碳 (CO2) 交换的贡献与主干和支流相比仍未得到充分研究.
研究的目的:
- 量化北极奥布河流域内的各种水体对碳循环的相对贡献.
- 评估洪水平原特征,如二次通道和湖泊在春季洪水期间对碳排放的影响.
主要方法:
- 实地测量了水化变量和温室气体 (GHG) 度和流量,在春季洪水高峰期间,在奥布河下游泛滥平原的900公里横段.
- 使用室内方法分析二氧化碳和甲 (CH4) 流量.
- 多参数数据的统计分析.
- 使用Landsat-8卫星图像来确定洪水平原的水覆盖面.
主要成果:
- 泛滥平原湖泊和二次通道是碳排放的重要贡献者,超过了主干和支流的流量.
- 陆地有机物丰富的淹水湿地 (fens) 增加二氧化碳排放,而二次通道中的地下水排放场所减少了二氧化碳排放.
- 在春季洪水期间,下奥布河泛滥平原水面的二氧化碳排放量为0.73 ± 0.25 Tg C,泛滥平原湖泊贡献了59%,主要茎34%.
- 分散的CH4流量不到总碳流量的1%.
- 洪水平原的水覆盖率在春季洪水期间达到30%,明显高于基流条件 (18%).
结论:
- 如果测量仅基于夏季低流量条件,那么北极河流的碳排放量可能会被低估至少三倍.
- 准确评估全球河流碳排放需要考虑水面延伸和高水位期间的相关排放,特别是在北极河流泛滥平原.
- 该研究强调了洪水平原动态在北极碳循环中的关键作用及其对气候反机制的影响.
更多相关视频
12:50Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds
Published on: September 26, 2017
11.2K
09:03Assessment of Methane and Nitrous Oxide Fluxes from Paddy Field by Means of Static Closed Chambers Maintaining Plants Within Headspace
Published on: September 6, 2018
12.2K
相关概念视频
Design Example: Analyzing Capacity Contours for Flood Risk Assessment
41
Flood risk assessment involves careful planning and analysis to ensure the safety of communities near water retention structures. Capacity contours are a vital tool in this process, as they illustrate the potential spread of water at specific levels in a given area. In the context of building a bund across a small valley, these contours play a critical role in evaluating the safety of nearby residential areas.In this example, the bund is intended to store stormwater in the valley. The engineers...
41
The Calvin Benson Cycle
4.5K
Ribulose 1,5- bisphosphate carboxylase/oxygenase (RuBisCo) is a critical enzyme that catalyzes carbon dioxide assimilation during photosynthesis. However, it is an inefficient enzyme, having an extremely slow catalytic rate. A typical enzyme can process about a thousand molecules per second; however, RuBisCo fixes only around three-carbon dioxides per second. Photosynthetic cells compensate for this slow rate by synthesizing very high amounts of RuBisCo, making it the most abundant single...
4.5K
Responses to Drought and Flooding
10.6K
Water plays a significant role in the life cycle of plants. However, insufficient or excess of water can be detrimental and pose a serious threat to plants.
10.6K
Global Climate Change
24.3K
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
24.3K
Adaptations that Reduce Water Loss
25.2K
Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and other cellular processes, evolutionary pressures on plants in different environments have driven the acquisition of adaptations that reduce water loss.
25.2K
The Carbon Cycle
37.1K
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
37.1K
