岸面侵蚀可以抵消跨越性屏障岛系统中蓝色碳的积累
Mary Bryan Barksdale1, Christopher J Hein2, Matthew L Kirwan2
1Virginia Institute of Marine Science, William & Mary, P.O. Box 1346, Gloucester Point, VA, 23062, USA. mbarksdale@vims.edu.
Nature communications
|December 19, 2023
概括
由于海平面上升造成的海岸侵蚀释放出大量的有机碳. 这种侵蚀超过了碳积累,挑战了海岸作为永久碳汇的观点.
科学领域:
- 沿海地质的地质学
- 地质化学 地质化学
- 气候变化科学 气候变化科学
背景情况:
- 海平面上升推动了沿海生态系统的迁移,影响了碳储存.
- 屏障岛屿的迁移可能导致碳丰富沉积物的埋葬或暴露.
- 了解跨越性沿海系统中的碳动态至关重要.
研究的目的:
- 为了量化来自弗吉尼亚大西洋海岸的海边侵蚀后壁沉积物的碳流.
- 为了比较最近的侵蚀率与相邻的土壤碳积累率.
- 评估不同类型的沉积物对整体碳损失的贡献.
主要方法:
- 使用侵蚀速率和碳密度量化碳流量.
- 对最近侵蚀时期的分析 (1994-2017年CE) ) 的情况.
- 与邻近的土壤碳积累率 (1984-2020) 的比较.
主要成果:
- 跨越屏障每年释放大约26.1千克有机碳.
- 侵蚀速度超过邻近的土壤碳积累率约30%.
- 湖沉积物的海岸表面侵蚀导致超过80%的总碳损失.
结论:
- 由于侵蚀,沿海的碳储存是暂时的.
- 现有的碳预算可能会高估沿海的碳沉积能力.
- 海平面上升需要重新评估沿海碳捕获.
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