Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (5): 644-659.DOI: 10.17521/cjpe.2022.0160

• Research Articles • Previous Articles     Next Articles

Effects of simulated nitrogen deposition on growth and decomposition of two bryophytes in ombrotrophic peatland, southwestern Hubei, China

LI Xiao-Ling1,2, ZHU Dao-Ming3, YU Yu-Rong1, WU Hao1, MOU Li1, HONG Liu1, LIU Xue- Fei1, BU Gui-Jun1, XUE Dan4, WU Lin1,*()   

  1. 1. School of Forestry and Horticulture, Hubei Minzu University, Enshi, Hubei 445000, China
    2. Institute of Chinese Herbal Medicines, Hubei Academy of Agricultural Sciences, Enshi, Hubei 445000, China
    3. The Central Hospital of Enshi Tujia and Miao Autonomous Prefecture, Enshi, Hubei 445000, China
    4. Chinese Academy of Sciences Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
  • Accepted:2022-09-28 Online:2023-05-20 Published:2023-02-28
  • Supported by:
    National Natural Science Foundation of China(41867042)


Aims Ombrotrophic peatlands, dominated by Sphagnum, are important carbon sinks in terrestrial ecosystems. The dynamics of growth and decomposition of dominant plants usually determine the carbon sink potential of ombrotrophic peatland. However, it is still controversial how nitrogen deposition impact on the growth and decomposition of mosses in ombrotrophic peatland. Moreover, the effects of nitrogen deposition on the growth and decomposition of dominant mosses are rarely reported in subtropical ombrotrophic peatlands.
Methods We selected an ombrotrophic peatland in southwestern Hubei Province as the study area. Different concentrations of NH4Cl solution were sprayed in situ. Here biomass harvesting and decomposition bag methods were adopted to estimate growth and litter decomposition of S. palustre and Polytrichum commune.
Important findings
(1) Nitrogen deposition had obvious effects on the height and biomass of the two mosses. Moreover, there was a threshold value of nitrogen deposition at the level of about 3 g·m-2·a-1. (2) The effects of nitrogen deposition on the growth of the two mosses were different, and the response sensitivity of S. palustre to nitrogen deposition was greater than that of P. commune. (3) High nitrogen deposition levels (i.e., 6 and 12 g·m-2·a-1) inhibited the decomposition of S. palustre, while the effect of low nitrogen deposition (i.e., 3 g·m-2·a-1) on the decomposition of S. palustre depends on time. All the concentrations of nitrogen deposition inhibited the decomposition of P. commune litter. (4) After one year of decomposition, the average final mass residual percentage of S. palustre was 105.99%, and 70.79% for P. commune. The decomposition rate of P. commune was much higher than that of S. palustre. (5) Nitrogen deposition significantly affected the chemical element content and stoichiometric ratio of the two moss litters, and was closely related to decomposition time.

Key words: Sphagnum bog, decomposition, moss, nitrogen input, production