Contrasting Effects of Plant Functional Traits, Functional Diversity and Abiotic Factors on Ecosystem Service Multifunctionality Across Inner Mongolian Steppe Types

Plant functional traits, as indicators of community responses to disturbances, are key drivers of ecosystem service multifunctionality (ESMF). However, the relative contribution of these traits to ESMF across different steppe types remains unclear. Using data from 101 sampling sites across Inner Mongolia’s meadow steppe (MS), typical steppe (TS), and desert steppe (DS), we examine the contributions and driving mechanisms of abiotic (climate and soil) and biotic factors (23 community-weighted mean functional traits and diversity indices) to ESMF across different steppe types. Our results show significant differences in ESMF across steppe types, with a decreasing trend from MS to TS to DS. Crucially, the driving factors of ESMF shift fundamentally across steppe types. In MS, ESMF is primarily driven by biotic factors (e.g., stem N:P ratio), whereas as aridity increases, abiotic factors (e.g., aridity and soil clay content) become more influential, ultimately dominating ESMF in DS. This shift from niche differentiation to environmental filtering as the dominant mechanism provides a crucial framework for predicting ecosystem service responses to global change. It highlights the importance of context-dependent grassland conservation strategies, advocating for location-specific management based on environmental gradients.