微生物社区呼吸动力学及其在沿海海水中的动态
Henry L S Cheung1, Rachel L Simister2, Christelle Not1
1Department of Earth Sciences, The University of Hong Kong, Pok Fu Lam Road, Hong Kong Special Administrative Region; The Swire Institute of Marine Sciences, The University of Hong Kong, Pok Fu Lam Road, Hong Kong Special Administrative Region.
The Science of the total environment
|September 22, 2024
概括
在香港,沿海微生物呼吸率在一年内被测量. 研究结果揭示了氧 afinities 的季节性变化,这对于预测脱氧对海洋生态系统的影响至关重要.
科学领域:
- 海洋微生物生态学
- 生物地质化学生物地质化学
- 海洋学 海洋学 海洋学
背景情况:
- 沿海海水氧气 (O2) 度正在下降,影响海洋生态系统和生物地化学循环.
- 微生物呼吸在脱氧过程中起着至关重要的作用,但其在低O2下的动力学知之甚少.
- 目前的模型通常依赖于实验室培养的有限数据,需要现场环境研究.
研究的目的:
- 在氧气条件下降的情况下,调查香港沿海微生物群落的呼吸动力学.
- 为了确定微生物呼吸速率和氧 afinities 的季节性变化.
- 为改进预测脱氧及其生态后果的模型提供经验数据.
主要方法:
- 在香港沿海水域对微生物呼吸率进行一年的现场测量.
- 量化动力参数,包括最大呼吸速率 (Vmax) 和氧气吸收的表面半和常数 (Km).
- 分析微生物群落组成的季节性变化及其与营养素,温度和生产力等环境因素的相关性.
主要成果:
- 平均Vmax在560±280至5930±800nmol O2 L-1 h-1之间.
- O2吸收的明显Km在50 ± 40和310 ± 260nmol O2 L-1之间变化.
- 运动参数的季节性变化与微生物群体的组成,营养素的可用性,温度和生产力有关.
- 沿海社区通常表现出低氧 afinities,在干旱季节观察到更高的 afinities.
结论:
- 这项研究为沿海脱氧水中的微生物呼吸提供了关键的现场动力参数.
- 微生物群落结构的季节性变化显著影响氧气消耗率.
- 这些发现可以增强脱氧程度及其对沿海生态系统和生物地球化学的影响的预测模型.
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