Linking species and functional diversity to leaf traits during sand-dune stabilization in the Mu Us Desert

Abstract Background Understanding the dynamics of species and functional diversity and their interrelationships during vegetation restoration is essential for assessing the effectiveness of ecosystem restoration. Yet, the mechanistic links between species diversity and functional diversity during vegetation restoration remain uncertain, with community-level functional traits likely mediating this relationship. Methods We studied a chronosequence of Artemisia ordosica -dominated dryland communities, including semi-fixed (D1), fixed (D2), soil-biocrusted fixed (D3), and shrub-herbaceous-fixed sand-dunes (D4). Thirteen leaf functional traits were measured, including leaf tissue density (LTD), and leaf dry matter content (LDMC). Community-weighted mean leaf functional traits (CWM-LFTs) were calculated using importance value-weighted averages. Results Species and functional diversity increased progressively from stages D1 to D4, with the coefficient of variation for CWM-LFTs ranging from 7.71% to 57.27%. Changes in species diversity during sand dune stabilization were linked to a strategy of slow growth and cumulative increases in LTD, LDMC, and leaf carbon content (LCC), improving the community’s physical defense and nutrient retention. Leaf structural traits mirrored diversity patterns, with LDMC most strongly linked to functional evenness, functional divergence and Rao’s quadratic entropy. Conclusions Our results show that both species and functional diversity increased progressively with sand-dune stabilization. The plant community followed a trajectory of increasingly complex strategies, shifting from stress-tolerant traits toward competition-adapted traits in later stages. The LDMC was strongly correlated with both species and functional diversity, serving as a key trait that mediates competitiveness and defense in resource-limited ecosystems. These findings highlight the importance of trait-based assembly in vegetation restoration and offer new insights for desertification control.