Journal of Resources and Ecology ›› 2020, Vol. 11 ›› Issue (3): 272-282.DOI: 10.5814/j.issn.1674-764X.2020.03.004

• Rangeland Ecosystem Function and Management • Previous Articles     Next Articles

Comparison of Methods for Evaluating the Forage-livestock Balance of Alpine Grasslands on the Northern Tibetan Plateau

CAO Yanan1, ZHANG Xianzhou3,4,*(), NIU Ben3, HE Yongtao3,4   

  1. 1. School of Earth Science and Engineering, Hebei University of Engineering, Handan 056038, Hebei, China
    2. Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China
    3. Lhasa Plateau Ecosystem Research Station, Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
    4. College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2020-02-08 Accepted:2020-03-20 Online:2020-05-30 Published:2020-06-16
  • Contact: ZHANG Xianzhou
  • About author:CAO Yanan, E-mail: caoyanan@hebeu.edu.cn
  • Supported by:
    The National Key Research and Development Program of China(2016YFC0502001);The Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20010201);The Strategic Priority Research Program of the Chinese Academy of Sciences(XDA19050502)

Abstract:

Livestock grazing is one of primary way to use grasslands throughout the world, and the forage-livestock balance of grasslands is a core issue determining animal husbandry sustainability. However, there are few methods for assessing the forage-livestock balance and none of those consider the dynamics of external abiotic factors that influence forage yields. In this study, we combine long-term field observations with remote sensing data and meteorological records of temperature and precipitation to quantify the impacts of climate change and human activities on the forage-livestock balance of alpine grasslands on the northern Tibetan Plateau for the years 2000 to 2016. We developed two methods: one is statical method based on equilibrium theory and the other is dynamic method based on non-equilibrium theory. We also examined the uncertainties and shortcomings of using these two methods as a basis for formulating policies for sustainable grassland management. Our results from the statical method showed severe overgrazing in the grasslands of all counties observed except Nyima (including Shuanghu) for the entire period from 2000 to 2016. In contrast, the results from the dynamic method showed overgrazing in only eight years of the study period 2000-2016, while in the other nine years alpine grasslands throughout the northern Tibetan Plateau were less grazed and had forage surpluses. Additionally, the dynamic method found that the alpine grasslands of counties in the northeastern and southwestern areas of the northern Tibetan Plateau were overgrazed, and that alpine grasslands in the central area of the plateau were less grazed with forage surpluses. The latter finding is consistent with field surveys. Therefore, we suggest that the dynamic method is more appropriate for assessment of forage-livestock management efforts in alpine grasslands on the northern Tibetan Plateau. However, the statical method is still recommended for assessments of alpine grasslands profoundly disturbed by irrational human activities.

Key words: aboveground biomass, alpine grasslands, carrying capacity, forage-livestock balance, Northern Tibetan Plateau