Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (4): 461-472.DOI: 10.17521/cjpe.2021.0339

Special Issue: 生态化学计量 青藏高原植物生态学:群落生态学

• Research Articles • Previous Articles     Next Articles

Effects of land degradation on soil and microbial stoichiometry in Qingzang Plateau alpine grasslands

WU Zan1,2, PENG Yun-Feng2,*(), YANG Gui-Biao2, LI Qin-Lu2,4, LIU Yang2,3, MA Li-Hua1, YANG Yuan-He2,4, JIANG Xian-Jun1,*()   

  1. 1College of Resources and Environment, Southwest University, Chongqing 400715, China
    2State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    3College of Resources and Environmental Science/Hebei Province Key Laboratory for Farmland Eco-Environment, Agricultural University of Hebei, Baoding, Hebei 071000, China
    4University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2021-09-22 Accepted:2022-01-08 Online:2022-04-20 Published:2022-02-16
  • Contact: PENG Yun-Feng,JIANG Xian-Jun
  • About author:(Jiang XJ,
    *(Peng YF,;


Aims Grassland is an important component of the terrestrial ecosystems in China, and plays a vital role in ecosystem productivity and functioning. During the past decades, 90% of natural grasslands have been degraded as a result of climate change and anthropogenic activities. Grassland degradation altered soil nutrient balance, exerting substantial impacts on ecosystem structure and functions. Our objective was to explore the responses of soil and microbial carbon (C), nitrogen (N) and phosphorus (P) stoichiometry to grassland degradation across the Qingzang Plateau alpine grasslands.

Methods We collected soil samples (0-10 cm) along the degradation sequence (i.e., non-degradation, moderate degradation and heavy degradation) from five sites across the “Three-River Source” region. By determination of soil and microbial C, N and P, we examined the changes in their contents and stoichiometric ratios with grassland degradation. We further synthesized data from the whole Qingzang Plateau alpine grasslands to validate the measured results using a meta-analytical approach.

Important findings Grassland degradation significantly reduced soil organic C, total N and total P contents and their stoichiometric ratios. Although microbial C and N content declined with degradation, change in microbial P content was limited along the degradation gradient. The microbial C:N:P ratios showed minimal responses to degradation. No obvious relationships were observed among soil and microbial C:N:P ratios. The above results indicate that soil microbes have the ability to maintain a given elemental composition despite variation in soil elemental composition following grassland degradation. From a long-term perspective, the nutrient-balance based soil quality promotion technology is able to effectively enhance grassland restoration and improve ecosystem service.

Key words: grassland degradation, nutrient limitation, stoichiometric homoeostasis, soil microorganisms, Qingzang Plateau