气候变化、火干扰与生态系统碳循环

Interaction among climate change,fire disturbance and ecosystem carbon cycle

随着全球变暖的日益显著,气候变化及其影响越来越受到广泛关注。火干扰作为森林生态系统碳循环的一个重要组成部分,其干扰过程是对碳的再分配过程,因而对区域乃至全球的碳循环产生重要影响。气候变化、火干扰与生态系统碳循环三者之间存在因果循环关系,正确认识气候变化与火干扰的复杂关系及双向反馈作用,以及火干扰在生态系统碳循环中的作用,这对制定科学合理的火干扰管理策略,提高生态系统管理水平,减少碳排放,促进碳增汇,减缓全球变化速率均有重要意义。从两个方面阐述了气候变化、火干扰与生态系统碳循环之间的交互作用关系:气候变化与火干扰相互影响关系及双向反馈作用,分别从气候变化对火干扰的影响及火干扰对气候变化的影响两个方面阐述了两者之间的相互影响关系;火干扰与森林生态系统碳循环的交互作用,分别从火干扰对森林生态系统碳循环的影响及模型方法在模拟火干扰对森林生态系统碳循环影响中的应用两个方面论述火干扰对森林生态系统碳循环的影响及其定量评价模型方法。目前火干扰直接碳排放的模型方法比较完善,而间接影响碳循环的模型方法并不成熟,许多方法局限于定性描述,因此,应进一步探讨集成实地测量、遥感观测和模型模拟的跨尺度火干扰对碳循环的影响研究,注重尺度的转换问题。最后,提出了气候变暖背景下火干扰管理的路径选择,以及对今后的研究方向进行了展望。

Climate change have been drawn wide attention by the government,academic field and the public.Meanwhile,those issues have a significant effect on fire disturbance and forest ecosystem carbon cycle.Climate warming is one key issue of global change and plays an important role on carbon cycling in terrestrial ecosystems.Carbon storage of forest ecosystem is a basic parameter of studying carbon exchange between forest ecosystem and atmosphere,and an essential factor of estimating the absorption and discharge of forest ecosystem.Biomass burning is the burning of living and dead vegetation.Biomass burning is a significant global source of gaseous and particulate matter emissions to the atmosphere.Biomass burning has long been recognized as a significant source of a number of important trace gas species and particulate matter to the atmosphere.Forest fires are a major contributor of atmospheric gaseous and particulate pollutants.In forest fires are emitted significant amounts of gaseous and particulate matter pollutants into the atmosphere.Forest fires can play a significant role in atmospheric chemistry and contribute to climate change.Forest fire emissions can be important for local air pollution levels.The potential climate change mitigation benefits of carbon sequestration by forested ecosystems have garnered both national and international attention.Biomass burning due to anthropogenic activities has significant impact on the atmospheric chemistry,climate and on the global biogeochemical cycles.In many regions of the world,fires are an important and highly variable source of air pollutant emissions,and they thus constitute a significant if not dominant factor controlling the interannual variability of the atmospheric composition.This paper reviews the recent advance in our understanding of interaction among climate change,fire disturbance and ecosystem carbon cycle and underlying mechanisms.It also discusses the state-of-the-art in quantifying fire disturbance and ecosystem carbon cycle in modeling and its applications to carbon cycle assessment.The paper has described systematically mutual interaction among climate change,fire disturbance and ecosystem carbon cycle from the two aspects of the system.The focus of the paper is climate warming on the impact of fire disturbance and two-way feedback.The paper has described from the impact of climate change on fire disturbance and fire disturbance to climate change affects two aspects of the interaction relationship between the two aspects,fire disturbance and forest ecosystem carbon cycle interaction,respectively,from the impact of fire disturbance on forest ecosystem carbon cycle model in the simulation of fire disturbance on forest ecosystems in the carbon cycle affect two aspects of discourse fire disturbance on forest ecosystem carbon cycle and its quantitative evaluation model approach.The has elaborated fire disturbance in the context of climate warming on the carbon cycle of forest ecosystems.Fire disturbance on the atmospheric carbon cycle and fire disturbance on biomass carbon pool,atmospheric carbon pool,soil carbon pool and its turnover,forest litter carbon pool and its turnover were expounded,respectively.The paper has examined the model of fire disturbance on forest ecosystem carbon cycle.It found that the fire disturbance with the direct carbon emissions more perfect model approach,while the indirect effects of the carbon cycle model is not mature,and many methods are limited to qualitative description.The problem of cross-scale fire disturbance on carbon cycling should be further explored,focusing on integration of field measurements,remote sensing observations and model simulation scale conversion.Finally,under the background of climate warming and the fire disturbance to the forest ecosystem and the effect to carbon cycle,the paper has proposed the effective forest fire management the measures as well as the present need to strengthen in some research area and research direction.