火干扰对森林生态系统土壤呼吸组分的影响研究进展

Research progress on effects of fire disturbance on soil respiration components in forest ecosystems

土壤呼吸是陆地生态系统与大气碳交换的主要方式,主要分为自养呼吸和异养呼吸。土壤呼吸不仅是森林生态系统碳循环过程的关键环节,也是森林生态系统能量流动和物质循环的重要生态过程。火作为森林生态系统中一个重要的生态因子,可以在短时间内对土壤呼吸组分造成巨大的影响。火干扰对土壤呼吸组分的影响与火烧强度、火烧频率、火烧持续时间以及火后恢复等因子有关,通过影响植被的根系与组成、微生物群落数量与结构,凋落物的数量以及生态系统的环境和小气候等,进而对土壤呼吸产生影响。火干扰对土壤呼吸影响整体表现为火烧后土壤呼吸速率下降,在几个月至几年内恢复到火烧前水平,之后火继续对土壤呼吸产生影响长达数年至数十年。通过描述火烧强度、火烧频率以及火后恢复时间,阐述火干扰对土壤呼吸组分的直接影响,以及通过火后环境对土壤呼吸组分产生的间接影响,来揭示火干扰对森林生态系统土壤呼吸组分的影响。同时针对火干扰对土壤呼吸组分的影响进行以下3个方面的研究展望:(1)火后产生的黑碳对土壤呼吸组分的影响;(2)火后植被恢复对土壤呼吸组分产生的影响;(3)火后土壤呼吸组分的长期变化规律。

Soil respiration is the main way of carbon exchange between terrestrial ecosystems and the atmosphere,which is mainly divided into autotrophic respiration and heterotrophic respiration.Soil respiration is not only a key link in the carbon cycle of forest ecosystems,but also an important ecological process of energy flow and material cycling in forest ecosystems.Fire,as an important ecological factor in the forest ecosystem,can have a huge impact on soil respiration components in a short time.The influence of fire disturbance on soil respiration components is related to factors such as fire intensity,fire frequency,fire duration,and post-fire recovery.By affecting the root system and composition of vegetation,the number and structure of microbial communities,the number of litters,and the environment and microclimate of the ecosystem,it then has an impact on soil respiration.The overall effect of fire disturbance on soil respiration is that the soil respiration rate decreases after a fire,and returns to the level before the fire within a few months to a few years.After that,the fire continued to affect soil respiration for several years to decades.This article mainly describes the intensity of fire,the frequency of fire,and the recovery time after fire,expounds the direct impact of fire disturbance on soil respiration components,and reveals the impact of fire disturbance on soil respiration components of forest ecosystem through the indirect impact of post fire environment on soil respiration components.At the same time,the following three research prospects are made regarding the influence of fire disturbance on soil respiration components:(1)the effects of black carbon produced after fire on soil respiration components;(2)the effects of vegetation restoration after fire on soil respiration components;and(3)the long-term change pattern of soil respiration components after fire.