Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (11): 1471-1482.DOI: 10.17521/cjpe.2022.0326

• Review •     Next Articles

Effects of warming on fine root phenology of forests: a review

CHEN Xin-Yi1,2,3, WU Chen1,2,3, HUANG Jin-Xue2, XIONG De-Cheng1,2,3,*()   

  1. 1Fujian Provincial Key Laboratory for Plant Eco-physiology, Fujian Normal University, Fuzhou 350007, China
    2School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China
    3Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, Fujian 365002, China
  • Received:2022-08-11 Accepted:2023-03-13 Online:2023-11-20 Published:2023-03-16
  • Contact: XIONG De-Cheng(xdc104@163.com)
  • Supported by:
    National Natural Science Foundation of China(32071743);National Natural Science Foundation of China(32192433);Public Welfare Projects of Science and Technology Department of Fujian Province(2022R1002004)

Abstract:

The fine root phenology of forests is an important indicator to observe the impact of global warming. It can reflect not only the growth status of forests under the background of global change but also the dynamics of the carbon cycle and below-ground carbon distribution of terrestrial ecosystems. Meanwhile, the response of forest fine root phenology to climate change is considered a hotspot and challenge in the field of global change effects, and thus has been studied extensively. Recent studies claim that soil warming will prolong the growing season of fine roots in forests as the spring phenology and growth peak will begin earlier in some areas of the northern hemisphere, however, atmospheric warming may inhibit the growth of fine roots and delay the phenological events. In addition, some studies found that the root phenology in the surface soil may be more affected by warming than that in the deep layer. Concurrently, some researchers associated fine root phenology with rhizosphere soil environment, microorganisms and above-ground phenology to reveal the response mechanism. However, the response of fine root phenology to climate warming and its underlying mechanisms have not been fully explained. This paper systematically reviewed changes in fine root phenology in forests under global warming, and aimed to provide references for the research on below-ground phenology, and the response and adaptation mechanism of forests to global changes. Future studies should enhance the research on the following aspects: 1) improving and exploring more accurate simulation warming devices and carrying out long-term quantitative research; 2) exploring the relationship between different functional modules of roots (such as absorbing root/transporting root, fibrous root/pioneering root) and their phenology under changing environments, i.e. “environment-traits- phenology”; 3) considering variations of the control factors of root phenology under different below-ground phenological phases (the beginning, peak and end of root growth), species and soil layers; 4) focusing on the relationship between below- and above-ground phenology, and its impacts on plant productivity; 5) focus on the changes of forest below-ground phenology and ecosystem functions (such as carbon sinks, nutrient cycling, etc.) under the combined effect of warming and other environmental factors (CO2 concentration, nitrogen deposition, etc.).

Key words: global warming, fine root dynamics, phenology, below-ground carbon allocation, vertical distribution