Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (5): 672-686.DOI: 10.17521/cjpe.2022.0111

Special Issue: 凋落物

• Research Articles • Previous Articles     Next Articles

Reduced release of labile carbon from Abies fargesii var. faxoniana needle litter after snow removal in an alpine forest

LAI Shuo-Tian1, WU Fu-Zhong1,2,3, WU Qiu-Xia1, ZHU Jing-Jing1, NI Xiang-Yin1,2,3,*()   

  1. 1. School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China
    2. Key Laboratory for Humid Subtropical Eco-Geographical Processes of the Ministry of Education, Fuzhou 350007, China
    3. Fujian Sanming Forest Ecosystem National Observation and Research Station, Sanming, Fujian 365002, China
  • Received:2022-04-01 Accepted:2022-09-04 Online:2023-05-20 Published:2022-09-06
  • Supported by:
    National Natural Science Foundation of China(32022056);National Natural Science Foundation of China(31800521);National Natural Science Foundation of China(32101509);National Natural Science Foundation of China(32171641)


Aims Changes in the depth and duration of seasonal snowpack induced by climate change may affect litter decomposition, particularly the release of labile carbon during the early decomposition periods in alpine forests. Our objective of this study was to assess the effect of snow removal on labile carbon fractions in litter (i.e., dissolved organic carbon (DOC), hot-water extractable carbon (HWEC) and non-structural carbon (NSC)) during early stage of litter decomposition in an alpine forest on the eastern Qingzang Plateau.
Methods An in situ litter input microcosm experiment was conducted in an alpine forest dominated by 120 to 150-year-old fir (Abies fargesii var. faxoniana) from October 2018 to October 2019. Air-dried fir needle litter was incubated at control and snow removal plots and the concentrations of total organic carbon (TOC), DOC, HWEC, NSC, soluble sugars and starch in decomposing fir litter were determined during winter (snow formation period, snow coverage period and snow melt period) and growing season (early, middle and late growing season).
Important findings Results showed that litter mass remained by 76.4% and 86.2% at control and snow removal plots, respectively, over one year of decomposition. After decomposition for one year, 60.5% and 74.8% of organic carbon remained in decomposing litter at control and snow removal plots, respectively. After decomposition for a winter, the release of HWEC and soluble sugars from decomposing litter were lower, while TOC, DOC, NSC and starch in fir needle litter were higher in snow removal plots than that in control plot. After decomposition for a growing season, the release of TOC, HWEC, DOC, NSC, soluble sugars and starch were reduced by 36.3%, 0.8%, 43.7%, 28.3%, 21.7% and 33.7%, respectively, in the snow removal plots compared to those in the control plots. The results from partial least square model indicated that labile carbon release was strongly controlled by soil freezing-thawing cycle, urease activity, soil temperature and DOC concentration. These results suggest that the presence of snow cover accelerated the release of labile carbon from decomposing litter during winter and growing seasons, highlighting the importance of seasonal snow cover in controlling litter decomposition in high-latitude and high-altitude ecosystems. Moreover, the significant influence of snow cover on labile carbon release during winter could have a legacy effect on litter decomposition during the subsequent growing season, suggesting that snow cover is of great significance for soil biogeochemical cycles in this alpine forest.

Key words: snow removal, needle litter decomposition, labile carbon, non-structural carbon, alpine forest