Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (7): 922-931.DOI: 10.17521/cjpe.2022.0105

Special Issue: 生态化学计量

• Research Articles • Previous Articles     Next Articles

Stoichiometric responses in topsoil and leaf of dominant species to precipitation change and nitrogen addition in an alpine meadow

LI Hong-Qin1,2,3, ZHANG Fa-Wei2,3,4,*(), YI Lü-Bei5   

  1. 1College of Life Sciences, Luoyang Normal University, Luoyang, Henan 471934, China
    2Institute of Sanjiangyuan National Park, Chinese Academy of Sciences, Xining 810008, China
    3National Ecosystem Science Data Center, Beijing 100101, China
    4Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China
    5Forestry Carbon Sink Service Center, Qinghai Forestry and Grassland Administration, Xining 810008, China
  • Received:2022-03-25 Accepted:2022-07-15 Online:2023-07-20 Published:2023-07-21
  • Contact: *ZHANG Fa-Wei(
  • Supported by:
    The National Key R&D Program of China(2017YFA0604802);The National Ecosystem Science Data Center(NESDC20210203);The Chinese Academy of Sciences-People’s Government of Qinghai Province Joint Grant on Sanjiangyuan National Park Research(LHZX-2020-07);The Project of Transformation of Scientific and Technological Achievements of Qinghai Province(2020-SF-145)


Aims Precipitation regime alteration and increasing nitrogen deposition have substantially altered the structure and function of grassland ecosystems. However, the responses of stoichiometry in soil and vegetation remain elusive, which limits the accuracy in predicting functional changes of alpine meadow.

Methods Based on a manipulation experiment platform of nitrogen addition (10 g·m-2·a-1) and precipitation change (precipitation reduction by 50% and increase by 50%) in an alpine meadow on the southern foot of Qilian Mountains, organic carbon (SOC), total nitrogen (SN), total phosphorus (SP) contents in topsoil (0-10 cm), and foliar carbon (LC), nitrogen (LN), phosphorus (LP) and potassium (LK) contents of dominant plant species, including Gentiana straminea, Elymus nutans, Oxytropis ochrocephalaand Kobresia humilis,were continuously surveyed from 2017 to 2020.

Important findings The soil stoichiometry varied significantly among different years, but was not affected by experimental treatments. The aboveground plant biomass showed inter-annual variations and was significantly affected by nitrogen addition. The responses of leaf stoichiometry were species-specific. Foliar stoichiometry of a resource-conservative species, E. nutans, showed limited variations, while that of the sensitive species, K. humilis, fluctuated significantly. To exclude the impacts of temporal variations, we conducted the analysis based on the relative changes (Δ) between treatment plots and the control plots from the same year and the results showed that nitrogen addition significantly increased ΔPB by 15.6%. Precipitation reduction significantly decreased ΔLC of O. ochrocephala by 6.8% while increased ΔLP of K. humilis by 19.8%. Our findings suggest that only nitrogen addition increased aboveground biomass and precipitation reduction altered LC and LP contents in some plant species. The temporal or species-specific effect, rather than experiment treatments effect, dominated the stoichiometric variations of soil and vegetation, highlighting the complex responses of alpine meadow to precipitation regime alteration and nitrogen addition.

Key words: alpine meadow, precipitation change, nitrogen addition, stoichiometry, dominant plant species