陆地氧循环过程研究进展

Advances in Researches of Terrestrial Oxygen Cycle Processes

氧循环是地球系统重要的生物化学循环之一,其变化对地球的宜居性有着重要影响。工业革命以来,由于人类活动的影响,现代氧循环相比地质年代的氧循环发生了巨大的变化。陆地氧循环过程在现代氧循环中具有举足轻重的作用。从陆地植被生态系统产氧、陆地燃料燃烧耗氧等方面对已有陆地氧循环过程研究进行了回顾,表明:①陆地过程的变化会直接造成大气氧气浓度的波动,对大气氧气浓度有预测作用;②陆地氧循环过程反映了生态系统对人类活动与气候变化的响应,对评估生态安全具有指示作用。通过探究陆地氧循环过程对气候变化与人类活动的反馈,有助于预测未来大气氧气浓度的变化,为未来区域发展政策制定提供参考。

Oxygen cycle is one of the essential global biogeochemical cycles on Earth,and the change of oxygen cycle is of great importance to the Earth habitability.Since the industrialization,due to anthropogenic disturbance,such as land use change and fossil fuel combustion,modern oxygen cycle has undergone drastic changes compared with the cycle in geologic time scale.As a consequence,modern oxygen cycle provides an innovate view on studying the response of Earth system to climate change and human activities,which has aroused the concern of the academic community.Terrestrial oxygen cycle processes,such as terrestrial ecosystem oxygen production and fuels combustion consumption,are important components of modern oxygen cycle.In the recent years,as the improvement of observing methods and biogeochemical models simulation,the key terrestrial oxygen cycle processes are better understood and estimated.By reviewing the previous studies on key terrestrial processes oxygen fluxes,the methods to estimate or observe the terrestrial oxygen fluxes are summarized,and the main terrestrial oxygen fluxes distribution patterns are presented.The change of terrestrial oxygen budget can directly influence the atmospheric oxygen concentration level through the change in consuming or producing oxygen,therefore playing essential roles in predicting future atmospheric oxygen concentration change.Also the indexes based on terrestrial oxygen cycle processes,such as oxygen footprint index and ecosystem security index,can reflect interactions among different Earth system components and exhibit the responses of ecosystem to climate change and anthropogenic activities,which help to evaluate the security of terrestrial ecosystem.Reviewing the advances in research of terrestrial oxygen processes can improve the understanding of modern oxygen cycle and explore the responses of terrestrial oxygen cycle processes to climate change and human beings activities.This can be helpful to predict the future variation in atmospheric oxygen concentrations and make developmental policies.