Effects of Salix psammophila sand barrier decomposition on soil bacterial and fungal community composition

To explore the effects of the decomposition of Salix psammophila mechanical sand barriers on the composition of soil bacterial and fungal communities.

Salix psammophila sand barriers deployed for 1, 3, 5, and 7 years were selected as research objects, with bare sandy land as the control (CK). Field in-situ sampling, indoor indicator measurements, and Illumina MiSeq sequencing technology were employed to reveal the response relationships between bacterial and fungal diversity, soil properties, and enzyme activity during the decay process of Salix sand barriers.

1) Soil organic carbon (SOC) and soil moisture content (SMC) increased significantly with the duration of deployment (SOC increased by 71.56% after 7 years compared to 1 year, and SMC increased by 79.90%); 2) Richness (Sobs and Ace indices) of bacterial communities peaked at 3 years of deployment, while diversity (Shannon index) was highest at 7; 3) Fungal diversity and richness generally showed an increasing trend, with Talaromyces dominating at 5 years, accounting for up to 83.25%, and the Shannon index of fungal communities significantly increased by 7 years; 4) Redundancy analysis indicated that bacterial communities were driven by SOC and alkaline phosphatase (APh), while fungal communities were primarily regulated by APh, SMC, and urease (Ure).

The decomposition of Salix psammophila mechanical sand barriers significantly influenced the structural and functional succession of microbial communities by altering soil physicochemical properties and enzyme activity, providing a scientific basis for optimizing sand barrier materials and evaluating ecological functions in desertification control.