沿海碳循环的过去变化和现状
1Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany, Institute for Geology, Universität of Hamburg, Hamburg, Germany.
Cambridge prisms. Coastal futures
|August 29, 2025
概括
海洋沿海生态系统大量储存碳,有助于减轻人类的二氧化碳排放. 然而,如果不减少排放,生态系统的恢复就无法抵消大气中二氧化碳水平的上升.
科学领域:
- * 环境科学
- * 海洋生物学
- * 气候科学
背景情况:
- 海洋沿海生态系统在全球碳循环中起着至关重要的作用,影响气候活性和地质储存之间的碳运输.
- 人类活动,特别是自1860年以来,已经破坏了以前的近乎稳定状态,导致大气二氧化碳度增加.
- 有关农业的土壤退化被假设通过增加石化物质供应来增强沿海生态系统的二氧化碳储存.
研究的目的:
- 分析沿海碳循环的历史和当前数据.
- * 评估海洋沿海生态系统在碳捕获中的作用及其对人类造成的变化的反应.
- * 评估生态系统恢复缓解大气二氧化碳增加的潜力.
主要方法:
- * 关于沿海碳循环的文献审查和数据综合.
- *从气候活性到地质碳循环的碳转移分析.
- * 评估海洋沿海生态系统中的二氧化碳储存.
主要成果:
- 海洋沿海生态系统覆盖了地球表面的5.8%,占地质循环中碳转移的55.2%.
- 人类活动已经从通过储存平衡二氧化碳 (在1860年之前) 转向增加大气中的二氧化碳.
- 生态系统的恢复提供了有限的碳吸收能力 (在底层系统中约为6%),不足以取代减排.
结论:
- 海洋沿海生态系统是重要的碳汇,但由于人为二氧化碳排放的增加,它们的容量正在被压倒.
- 虽然生态系统恢复可以为碳预算做出贡献,但它不能取代减少二氧化碳排放以应对全球变暖.
- 需要进一步的研究来量化沿海生态系统变化的气候影响,包括温室气体排放 (CH4,N2O) 和海上生态系统的碳吸收.
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