概括
蓝藻和地环境的海洋固是显著的,但不足以支持浮游生物的生长. 这表明其他因素,而不是限制,控制了海洋中的浮游生物的生产力.
科学领域:
- 海洋生物学 海洋生物学
- 海洋学 海洋学 海洋学
- 生物地质化学生物地质化学
背景情况:
- 固化对海洋生态系统至关重要,其中蓝藻细菌 (例如,Trichodesmium) 和谷底环境是关键贡献者.
- 估计表明海洋固是陆地固和工业氨合成的一小部分.
- 当输入与脱损失相平衡时,海洋循环被认为处于稳定状态.
研究的目的:
- 量化海洋固对全球预算的贡献.
- 评估海洋固的适度,以满足海洋浮游植物的需求.
- 调查固速率对理解植物浮游生物生长限制的影响.
主要方法:
- 从振荡体 (Trichodesmium) 和谷底环境中输入的定量分析.
- 海洋固速率与陆地固和工业氨生产的比较.
- 评估固定对植物浮游植物需求的贡献.
- 通过比较输入和脱损失来评估海洋循环的平稳状态.
主要成果:
- 振荡虫 (Trichodesmium) 每年为海洋贡献大约4.8 x 10^12克的.
- 地环境每年贡献大约15 x 10^12克的.
- 海洋固提供了海洋浮游植物所需的的不到0.3%.
- 海洋循环接近稳定状态,平衡输入和脱.
结论:
- 固化虽然很大,但对整个海洋经济的贡献很小.
- 固化的有限贡献挑战了是植物浮游生物的主要限制营养素的概念.
- 除了的可用性之外,其他因素可能会限制海洋中的浮游植物生长率.
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