海洋酸化对碳、氮和硫循环的影响

Effects of Ocean Acidification on Cycles of Carbon,Nitrogen and Sulfur

工业革命以来,大气CO_2浓度呈现快速增加的趋势,随之而来的问题是海洋酸化的程度越来越明显。与工业革命前相比,目前海洋表层海水pH降低了0.1个单位,到本世纪末估计会降低0.4个pH单位。本文综述了海洋酸化对碳、氮和硫循环的影响,包括碳循环中的溶解度泵、碳酸盐泵、软组织泵和微型生物碳泵,海洋酸化对氮循环中氮的固定、硝化作用、反硝化作用、N_2O的产生的影响,海洋酸化与硫循环中二甲基硫(DMS)的产生及其与食物网结构之间的关系。海洋酸化无论是以直接或间接方式均会在一定程度上对碳、氮和硫的生物地球化学循环产生影响,最终改变海洋系统的结构与功能。在自然界中,海洋酸化不是一个独立的过程,而是与其他物理、化学、生物变化因素相偶联共同作用于碳、氮和硫的生物地球化学循环。

The rapid increasing trend of concentration of carbon dioxide (CO2)compounded with the ocean acidification has been obvious since the industrial revolution.The current pH value in ocean surface waters is 0.1unit lower than in pre-industrial revolution and pH is predicted to decrease by 0.4 units by the end of this century.This review discussed the effects of ocean acidification on cycles of carbon,nitrogen and sulfur,including the roles of solubility pump,the carbonate pump,the soft-tissue carbon pump and the microbial carbon pump in the carbon cycle.The variations of nitrogen fixation,nitrification,denitrification and N2O production in nitrogen cycle and the relationships between DMS production and food web structure are also discussed.Ocean acidification changed,directly or indirectly, the biogeochemical cycles of carbon,nitrogen and sulfur in some degree,and then changed the structure and function of the whole ocean system.In natural environments,ocean acidification acted on biogeochemical cycles of carbon,nitrogen and sulfur with other physical,chemical and biological factors.