Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (5): 660-671.DOI: 10.17521/cjpe.2021.0321

• Research Articles • Previous Articles     Next Articles

Effects of forest gap on losses of total phenols and condensed tannins of foliar litter in a subalpine forest of western Sichuan, China

DU Ting1, CHEN Yu-Lian1, BI Jing-Hui2, YANG Yu-Ting1, ZHANG Li1, YOU Cheng-Ming1, TAN Bo1, XU Zhen-Feng1, WANG Li-Xia1, LIU Si-Ning1, LI Han1,*()   

  1. 1. Institute of Ecology and Forest of Sichuan Agricultural University, Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province, National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River, Long-term Research Station of Alpine Forest Ecosystems, Chengdu 611130, China
    2. Chongqing University of Arts and Sciences, Chongqing 402160, China
  • Received:2021-09-09 Accepted:2022-04-22 Online:2023-05-20 Published:2022-04-22
  • Supported by:
    National Natural Science Foundation of China(31901295);National Natural Science Foundation of China(32071745);National Natural Science Foundation of China(31870602);Program of Sichuan Excellent Youth Sci-Tech Foundation(2020JDJQ0052);Program of Sichuan Applied Basic Research Foundation(2021YJ0340)

Abstract:

Aims As key components in plant litters, the total phenols and condensed tannins greatly regulate decomposition process of forest litter, which can be directly or indirectly affected by forest gaps. The aim of this study was to determine how the forest gaps would affect the losses of total phenols and condensed tannins of foliar litter during decomposition in subalpine forest.
Methods We conducted a three-year in situ litter decomposition experiment on different forest gaps (i.e. gap center, canopy gap, expanded gap, closed canopy) in a subalpine forest of western Sichuan, and six foliar litters including Juniperus saltuaria, Abies fargesii var. faxoniana, Larix mastersiana, Betula albosinensis, Salix paraplesia and Rhododendron lapponicum were selected. The measurements were conducted to examine the losses of litter total phenols and condensed tannins during winter and growing season.
Important findings Litter total phenols and condensed tannins showed higher loss rates in the first decomposition year, with the levels of 10.76 mg·d-1 and 8.5 mg·d-1, respectively. The effects of forest gaps on the degradation of phenolic components gradually were getting weak with the litter decomposition proceeding, and exhibited obvious seasonal differences. The total phenols content of six litters all decreased rapidly in the growing seasons, while litters with higher initial condensed tannins with faster loss rate were found in the first winter, suggesting that both litter quality and seasons would significantly alter litter phenolic components losses during long-term decomposition under forest gaps. These results are helpful for deeper understanding of the litter decomposition process and nutrients cycling in forest ecosystems, which provide scientific data to improve the development of management policies in subalpine forests.

Key words: forest gap, decomposition, total phenols, condensed tannins, seasonal dynamic, subalpine