溪流二氧化碳排放研究进展

陆源碳经内陆水体生态系统输出是全球碳循环的关键一环,其中溪流碳排放超过内陆水体平均碳排放,影响区域乃至全球碳收支.本文通过对前人的研究结果进行总结,归纳了当前溪流二氧化碳分压(pCO2)、二氧化碳排放通量(FCO2)的动态变化特征,二者均表现出明显的昼夜变化和季节变化特征,且随溪流分级的增大而减小;梳理了影响溪流pCO...

A review of carbon dioxide emissions from streams

The export of terrestrial carbon via inland aquatic ecosystems is a key process in global carbon cycle.Carbon emission from streams is greater than average carbon emission from inland water bodies,affecting the regional and global carbon budget.We summarized the temporal change of partial pressure of carbon dioxide(pCO₂) and carbon dioxide flux(FCO₂) across water bodies and atmosphere.Both pCO₂ and FCO₂ showed significant diurnal and seasonal variations,and decreased with increasing stream order.We discussed the physical,hydrochemical,and biological factors affecting stream pCO₂ and FCO₂,such as flow velocity,pH,and aquatic biomass.The contribution of autochthonous organic carbon to FCO₂ increased with stream order,which was usually lower than 50%.We outlined the challenges in future research on stream carbon cycling,such as measurement technical problems and the lack of continuous monitoring over time.We hope this review could provide new ideas and future research directions to enhance our understanding on the role of streams in the global carbon cycle.