The Gradient Heterogeneity of Deserts Alters the Interaction Relationships Between Xerophytic Plants and Soils

Desert ecosystems pose extreme challenges to plant survival. This study explores the adaptive strategies of two xerophytic halophytes, <i>Alhagi sparsifolia</i> and <i>Nitraria roborowskii</i>, in Xinjiang's Ebinur Lake wetland, focusing on their plant-soil-microbe (PSM) coupling systems across desert gradients. Results revealed significant interspecific and gradient-dependent differences in plant functional traits: <i>A. sparsifolia</i> showed high growth plasticity with a fast-growth strategy, while <i>N. roborowskii</i> adopted a conservative strategy. Rhizosphere soil physicochemical properties and microbial community structure exhibited strong spatial heterogeneity and host specificity, with <i>N. roborowskii</i> having a more complex microbial network and <i>A. sparsifolia</i> showing higher modularity. Multivariate factor analysis elucidated couplings among plant traits, soil properties, enzymes, and microbes. The two species form distinct interaction systems adapted to desert saline-alkali stress, advancing the understanding of ecological adaptation and informing restoration.