水生生态系统的碳循环及对大气CO_2的汇

Aquatic ecosystems: carbon cycle and as atmospheric CO_2 sink

水生生态系统 ,特别是海洋无疑是大气 CO2 的一个巨大的汇。海洋对大气 CO2 的汇以及大气圈和海洋之间碳的变换量在很大程度上取决于混合层碳酸盐化学、水中溶解碳的平流传输、CO2 通过空气——海水界面的扩散、海洋生物生产和所产生的有机碳化合物的沉降等 ,现在已建立和发展了多种海洋碳子模型以对 CO2 的汇进行估测。根据国内外研究资料 ,综述了水生生态系统碳循环过程及“生物泵”作用机制等方面的研究进展 ;介绍了两大类主要的海洋碳子模型 :厢式模型和普通环流模型 ,采用这些模型对海洋碳汇的估算约为 1 .2～ 2 .4 Gt C/a;分析了湖泊、河流等对大气 CO2 汇的特点及向海洋的转移 ,并对影响水体生态系统碳循环和大气 CO2

Aquatic ecosystem, especially ocean, is a huge sink of atmospheric CO 2. The ocean's role in regulating the uptake capacity of CO 2 and the carbon exchange between atmosphere and ocean involve a combination of inorganic carbon chemistry in mixing layer, advection transfer of carbon dissolved in ocean water, CO 2 diffusion through the interface of air and water, and various biotic processes, biological interactions in the upper ocean. Many models have been estabolished and developed in oredr to evaluate sink of CO 2 in the ocean. In this paper, it is summarized that the research progresses on carbon cycle in aquatic ecosystem and action mechanism of 'biological pump', as well as two kinds of models: box model (BM) and general circulation model (GCM). Based on the model mentioned above estimates of the net ocean sink for CO 2 range from 1.2 to 2.4 GtC/a. The transport and storage of atmospheric carbon in lake, river and reservoir are analysed. The factors that affect the carbon cycle and the sink capacity of atmospheric CO 2 in aquatic ecosystem were discussed as well.