在河水中,溶解的有机物自组织为状微粒
Martin Kerner1, Heinz Hohenberg, Siegmund Ertl
1University of Hamburg, Institute for Hydrobiology and Fishery Science, D-22765 Hamburg, Zeiseweg 9, Germany. kerner@uni-hamburg.de
Nature
|March 14, 2003
概括
溶解有机碳 (DOC) 的非生物聚合形成微粒,绕过微生物循环. 这种非生物过程对水生生态系统中的碳转移作出了重大贡献,挑战了当前的模型.
科学领域:
- 环境科学环境科学
- 水生生态学 水生生态学
- 生物地质化学生物地质化学
背景情况:
- 微生物循环描述了水生系统中的细菌将溶解有机物 (DOM) 转化为有机颗粒物.
- 这一过程对于将能量转移到更高的食物层至关重要,并影响水生生物的生产力.
研究的目的:
- 研究溶解有机碳 (DOC) 在微粒子中的无生物聚合.
- 为了确定这种非生物途径是否绕过碳转移中的微生物循环.
主要方法:
- 实验室化了无菌过的河水.
- 对溶解有机碳 (DOC) 聚合成微粒 (0.4-0.8微米) 的分析.
- 稳定碳同位素分析以追踪碳路径.
主要成果:
- 高达25%的溶解有机碳 (DOC) 无生物聚合成微粒.
- 聚合是通过低至高分子量DOC的扩散发生的.
- 微粒的组成表明它适合作为浮游生物菌的食物,同位素分析证实了这一点.
结论:
- 微粒的非生物形成为DOC转移到更高的营养水平提供了直接途径,绕过了微生物循环.
- 目前对水生系统中碳循环的理解可能需要修订,以包括这种非生物聚合途径.
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