Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (11): 1493-1506.DOI: 10.17521/cjpe.2022.0426

• Research Articles • Previous Articles     Next Articles

Effects of simulated nitrogen deposition on physiological and morphological characteristics of Sphagnum in wetland, southwestern Hubei Province, China

YU Yu-Rong1,2, WU Hao1,2, GAO Ya-Fei1,2, ZHAO Yuan-Bo1,2, LI Xiao-Ling2,3, BU Gui-Jun1,2, XUE Dan4, LIU Zheng-Xiang5, WU Hai-Wen5, WU Lin1,2,*()   

  1. 1Biological Resources Protection and Utilization of the Key Laboratory of Hubei Province, Enshi, Hubei 445000, China
    2Forestry and Horticulture College, Hubei Minzu University, Enshi, Hubei 445000, China
    3Institute of Chinese Herbal Medicines, Hubei Academy of Agricultural Sciences, Enshi, Hubei 445000, China
    4Key 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
    5Institute of Ecological Conservation and Restoration, Chinese Academy of Forestry, Beijing 100091, China
  • Received:2022-10-28 Accepted:2023-02-15 Online:2023-11-20 Published:2023-12-22
  • Contact: WU Lin (
  • Supported by:
    National Natural Science Foundation of China(41867042);Basic Research Funds for Public Welfare Research Institutes of the Central Government(CAFYBB2020ZC005)


Aims Sphagnum, as the dominant species in Sphagnum wetland, is the most important carbon (C) sequestration plant. The physiological and morphological characteristics of Sphagnum determine the carbon sink potential of Sphagnum wetland. Nitrogen (N) deposition has a significant effect on the physiological and morphological characteristics of Sphagnum,but the effects of N deposition on such characteristics of Sphagnum in the wetland environment remain controversial. Moreover, there are few reports on the physiological and morphological characteristics of Sphagnum in subtropical wetlands.

Methods We selected a Sphagnum wetland in southwestern Hubei Province as the study area. Different concentrations of NH4Cl solution were sprayed in situto investigate the effects of simulated N deposition on physiological and morphological characteristics of Sphagnum. Four N concentrations were applied, namely 0 (N0), 3 (N3), 6 (N6) and 12 g·m-2·a-1 (N12), with N0 representing the control (CK).

Important findings (1) Nitrogen deposition had significant effects on the contents of total C and total N in Sphagnum. Among the treatments, the contents of total C and total N in Sphagnumunder the N3 treatment were the highest, and compared with those of the CK, increased by 3.78% and 88.52%, respectively. (2) Nitrogen deposition had no obvious effect on chlorophyll content and fluorescence activities of Sphagnum. However, N deposition significantly promoted the antioxidant enzyme activities and the contents of osmotic substances in Sphagnum,especially the contents of soluble sugars and peroxidase activity. (3) With the increase in N deposition, the height, branch number, mass per plant, and leaf cell area of Sphagnum tended to initially increase and thereafter decrease. The maximum values were observed in response to N deposition of 3 g·m-2·a-1. (4) Sphagnum was sensitive to N deposition, and there was a certain load value of the effect of N deposition on physiological and morphological characteristics of Sphagnumafter 2 years treatment, which was approximately 3 g·m-2·a-1. When the amount of N deposition is greater than 3 g·m-2·a-1, the effects on morphological indicators of Sphagnum are detrimental and the stress to Sphagnumwill increase significantly. The results of this study indicated that the current natural atmospheric N deposition is beneficial to the growth of Sphagnum in the wetland in southwestern Hubei Province. However, continual or doubled N deposition might be harmful to the growth of Sphagnum.

Key words: Sphagnum, nitrogen input, chlorophyll, antioxidant enzymes, morphology