Potentilla anserina reshapes soil-microbe networks in alpine meadow restoration

The formation of bare patches in degraded alpine meadows represents a critical bottleneck for ecological restoration. Potentilla anserina can rapidly cover exposed soil surfaces owing to its strong capacity for asexual reproduction. However, whether its secondary ecological functions extend beyond physical coverage remains unclear. In August 2024, rhizosphere and bulk soil samples were collected from both bare patches and P. anserina-colonized patches and analyzed via 16S rRNA and ITS high-throughput sequencing. The results revealed that the ameliorative effects of plants on soil physicochemical properties and microbial biomass extended beyond the rhizosphere, achieving overall optimization of the soil environment within patches. Analysis of community assembly processes based on βNTI revealed that colonization by plant synchronously increased the relative importance of environmental selection in both rhizosphere and bulk soil bacterial communities, indicating a global regulatory effect on bacteria. |βNTI| > 2 indicated deterministic assembly (environmental filtering), whereas |βNTI| < 2 reflected stochastic processes, which were further parsed by RC_bray: < -0.95 for homogenizing dispersal and >0.95 for dispersal limitation. In contrast, dispersal limitation was significantly greater only in the rhizosphere for fungal communities, indicating strict rhizosphere specificity. This divergent assembly process led to a simplified structure in bacterial communities, whereas fungal communities, through their unique ecological strategies, retained more original characteristics while acquiring a more complex and stable network structure. Network analysis identified an unclassified bacterium and a Preussia fungus as potential keystone taxa, which may drive soil regulation and organic matter decomposition, respectively, though functional validation is still required. This study elucidates the soil improvement and microbial regulatory mechanisms driven by P. anserina roots, highlights the divergent assembly processes between rhizosphere and bulk soil microbial communities, and provides theoretical support for the restoration of degraded alpine meadows. A key limitation is that this study was conducted at a single time point; seasonal and interannual dynamics may alter the observed patterns, and future work should incorporate temporal sampling and functional assays to validate the inferred keystone roles.