非生产性水生生态系统的二氧化碳平衡
1Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Cientificas, Cami de Santa Barbara s/n, 17300 Blanes, Girona, Spain.
概括
水生生态系统的呼吸量与生产力相变,影响它们是否释放或消耗二氧化碳. 不富有生产力的生态系统是碳的来源,而富有生产力的生态系统可以是碳的沉.
科学领域:
- 生态生态学 生态生态学
- 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:
- 水生生态系统在全球碳循环中发挥着至关重要的作用.
- 了解初级生产和呼吸之间的平衡是确定生态系统作为碳来源或碳汇的功能的关键.
- 之前的研究已经探索了这些动态,但在各种水生环境中扩大关系需要进一步调查.
研究的目的:
- 在水生生态系统中,研究社区呼吸 (R) 和总初级产量 (P) 之间的缩放关系.
- 确定这种关系如何影响水生生物群作为二氧化碳来源或沉积点的作用.
- 为了比较不同水生生态系统类型 (如沼泽和公海) 中的自养的生产率值.
主要方法:
- 对社区呼吸率和总初级生产率的现有数据的分析.
- 应用权力法缩放模型来关联R和P.
- 对生态系统特征和生产率水平进行比较分析.
主要成果:
- 社区呼吸率 (R) 尺度,总初级产量 (P) 在三分之二的功率 (R ~ P^2/3).
- 非生产性的水生生态系统具有不成比例的更高的呼吸率,通常是异质的 (R > P),并作为二氧化碳净来源.
- 水生生态系统实现自身养所需的总初级产量 (P > R) 在沼泽地区明显高于公海地区.
结论:
- 水生生态系统的生产率水平决定了其作为二氧化碳来源或沉降器的作用.
- 上层海洋的很大一部分是净异质的,但这种碳需求可以通过高生产率的地区来抵消.
- 生态系统类型显著影响平衡呼吸和实现自身养所需的生产力.
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