5 Conclusions
In desert steppe, the introduction of sheep grazing will not lead to shrub encroachment. Without grazing, the desert steppe would be encroached by shrubs, while perennial grasses would have an absolute dominance under chronic high stocking rates. The mixture of shrubby and herbaceous plants was dynamic across the stocking rate gradient and desert steppe plant communities would have multidirectional succession pathways under different long-term stocking rates.
ACKNOWLEDGMENTS
We thank Liu Bai, Yuanyuan Cui and many students for collecting data in field, and long-term support from Inner Mongolia Academy of Agriculture and Animal Husbandry. This study was supported by the National Science Foundation of China (31760143, 31660679, 31770500), National Key Research and Development Program of China (2016YFC0500504), Inner Mongolia Key Project (zdzx2018020), and the Innovative Team of Grassland Resources from the Ministry of Education of China (IRT_17R59).
CONFLICT OF INTEREST
The authors declare no conflicts of interest.
AUTHOR CONTRIBUTIONS
Guodong Han and Zhongwu Wang conceived and designed the experiments. Baolong Yan performed the experiments and wrote the main manuscript text. Shijie Lv analyzed the data and contributed to manuscript editing. Zhanwen Wang and Xiaohui Song performed the experiments.
DATA ACCESSIBILITY
All data (standing crop, cover, density and height) from this manuscript are publiaaly available in the FigShare datebase.
ORCID
Baolong Yan https://orcid.org/0000-0002-1873-3726
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