在碳和输入后,热湖中的有机物加速分解
Ziliang Li1,2,3, Weijie Xu1,2,3, Luyao Kang1,2,3
1State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
Global change biology
|September 11, 2023
概括
在西藏热湖中溶解的有机物生物降解是由可变碳和输入刺激的,从而放大了碳气候反. 这些发现凸显了永久土地区营养素供应的关键作用.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 微生物学 微生物学
背景情况:
- 在热岩湖中溶解有机物 (DOM) 的矿化对于永久土的碳 (C) 循环至关重要.
- 了解DOM生物降解是复杂的,因为与外部碳 (C) 和营养投入的相互作用,称为水生原始化和营养效应.
研究的目的:
- 调查30个西藏高原热岩湖的DOM生物降解,水生原始化和营养效应的大规模模式和驱动因素.
- 为了确定可变碳 (C) 和营养物质 ( (N) 和 (P)) 输入对DOM生物降解的影响.
主要方法:
- 大规模的湖泊采样和实验室化.
- 13C稳定同位素标记,光学光谱和高通量测序.
- 对DOM质量,微生物群落结构和营养度的分析.
主要成果:
- 不稳定的C和P输入显著刺激了DOM生物降解,原始化和P效应分别增加了172%和451%.
- 微生物活动受到C和营养素的共同限制,因为联合添加产生了更强的矿化.
- 水中原始化强度与DOM复原和细菌多样性有正相关,而P效应与DOM复原和营养度下降.
结论:
- 外部C和P输入显著提高了热湖中的DOM生物降解.
- 这些过程放大了阿尔卑斯山永久土地区的C气候反.
- 在这些生态系统中,DOM质量和营养素的可用性是微生物矿物化的关键调节因素.
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