Ecosystem service multifunctionality in typical and desert steppes under different grazing management strategies

Grasslands play a critical role in delivering diverse ecosystem services (ESs), yet they face growing threats from unsustainable grazing practices. This study investigates the impacts of three grazing management strategies-no grazing (NG), deferred grazing (DG), and continuous grazing (CG)-on multiple ESs and ecosystem service multifunctionality (ES-multifunctionality) in the typical and desert steppes of Inner Mongolia. We quantified ten ESs across provisioning, regulating, and supporting categories and assessed their trade-offs and synergies using a trade-off index and correlation analysis. ES-multifunctionality was evaluated using a multi-threshold approach under four weighted scenarios. Results showed that grazing duration significantly affected both individual ESs and ES-multifunctionality. NG consistently promoted higher ESs and ES-multifunctionality, while CG caused substantial declines, with ES-multifunctionality over 0.34 lower than NG at all thresholds. Trade-offs among ESs intensified under CG, whereas synergies predominated under NG. DG moderated trade-offs among ESs, maintaining intermediate levels of ES-multifunctionality, which were 0.01-0.37 lower than those under NG across all thresholds. In the typical steppe, both synergies and trade-offs occurred, while in the desert steppe, synergies predominated with only one weak trade-off. ES-multifunctionality values under NG were similar between steppe types with differences of less than 0.09, but under DG and CG those were higher in the typical steppe with differences of 0.01-0.33. These findings highlight the ecological benefits of deferred grazing practices for sustaining grassland multifunctionality and provide critical insights for adaptive grassland management policies in arid and semiarid regions.