增温对林木细根寿命影响的研究进展

Effects of warming on fine root lifespan of forests:A review

细根寿命作为林木生长的重要参数,不仅对林木吸收水分和养分能力具有重要作用,而且影响林木对光合产物的地下分配以及森林生态系统碳循环过程。气候变暖对细根寿命的影响已成为全球变化背景下关注的热点问题,细根寿命对全球变暖的响应将影响到生态系统的碳平衡。本文就林木细根寿命对增温的响应特征及其响应机制的研究进展进行综述,以期揭示增温对林木细根寿命的影响。目前已开展的大部分研究认为,增温会通过改变根际土壤环境、细根形态以及林木物候等指标来影响细根寿命。但细根生长和死亡受诸多因素的影响,导致增温对细根寿命影响的研究结果因研究区域自然环境、增温方式和研究对象等因素存在分歧。因此,综合分析气候变暖背景下林木细根寿命的变化对研究地下生态学过程至关重要。今后还应加强以下研究:1)结合多种方式进行地下、地上同时增温,并探索更准确和有效的无损观测方法;2)结合多种观测手段研究增温对细根寿命的影响;3)开展增温对不同树种细根寿命的研究,深入理解不同林木细根寿命对增温的响应机理;4)多角度综合分析增温对细根寿命的影响特征,探究多种因素综合作用对细根寿命的影响机理;5)增温与其他环境因子对细根寿命交互作用;6)增温后根系层级结构对细根寿命影响;7)增温后根际微生物(细菌、真菌)的改变对细根寿命影响。

As an important parameter of forests growth,fine root lifespan plays an important role in plant water and nutrient absorption,and affects underground distribution of photosynthetic products and forest ecosystem carbon cycling.The impact of climate warming on fine root lifespan has become a hot issue under the context of global change.The responses of fine root lifespan to global warming will affect ecosystem carbon balance.We reviewed the research progress of the response characteristics and mechanism of fine root lifespan of trees to warming.Most studies proposed that warming would affect fine root lifespan by changing rhizosphere soil environment,fine root morphology,and tree phenology.However,the growth and death of fine roots were affected by lots of factors,leading to differences in the research results on fine root lifespan due to natural environment of the study area,the way of warming,and the research objects.Therefore,it is of importance to comprehensively analyze the responses of fine root lifespan in forests under the background of climate warming to study the underground ecological process.In the future,the following research should be strengthened:1)Combining multiple methods to warming underground and aboveground simutaneously,and explore more accurate and effective non-destructive observation methods.2)Combining multiple observations to study the effects of warming on fine root lifespan.3)Carrying out research on the effect of warming on fine root lifespan of different tree species,and deeply understand the response mechanism of fine root lifespan of different trees to warming.4)A comprehensive analysis of the effects of warming on fine root lifespan from various perspectives,and an investigation into the mechanism of the combined effects of various factors on fine root lifespan.5)The interaction between warming and other environmental factors fine root lifespan.6)The effect of root architecture on the fine root lifespan after warming.7)The effects of rhizosphere microorganisms(bacteria and fungi)on fine root lifespan after warming.