With the increase in setting years in deserts, Salix psammophila sand barriers with different degrees of lodging damage caused by decay are losing wind-prevention and sand-fixation properties. In this study, we focus on the change in chemical properties of soils, and physical and mechanical properties of plants along different setting years; meanwhile, the change in fungal communities has been analyzed using high-throughput sequencing technology. The results show that a change in physical and mechanical properties and the loss of primary chemical components led to the degradation of the protective properties of the barrier to different degrees. After five years of setting, the physical parameters of basic density and shrinkage rate decreased by 44.04% and 28.68%, respectively, and the loss of the modulus of rupture mechanical index declined by 62.72%. After seven years of setting, the mechanical indexes of the modulus of rupture decreased by 76.95%. Five and seven years represented important inflection points in the decay process. Sordariomycetes (53.75%) and Eurotiomycetes (19.78%) were the main fungal groups present during the decay of the sand barrier. The basic density, moisture content, cellulose, and lignin of the sand barrier were the main driving factors affecting the distribution of fungal communities. The mechanism on fungal community to the decay of sand barriers still needs further studies to keep the function of sand barriers in fragile desert ecosystems.

The construction of photovoltaic (PV) power stations for sand control in northwestern China has exacerbated the conflict between solar resource utilization and ecosystem fragility, creating urgent ecological challenges that demand immediate solutions. This study investigated Amorpha fruticosa growing under fixed adjustable PV panels at the CGN DaLate Photovoltaic Leading Base in the eastern hinterland of the Kubuqi Desert. Through long-term field observations, three shading time gradients were established: heavy shading (HS), light shading (LS), and no shading (CK, control). The results clearly demonstrated that: (1) Plants in the LS treatment exhibited significantly greater plant height, basal diameter, and crown width compared to those in HS and CK, indicating optimal growth status and morphological plasticity. They maintained the highest net photosynthetic rate (Pn) and water use efficiency (WUE), while their intercellular CO₂ concentration (Ci) was significantly lower than in CK, effectively mitigating photosynthetic inhibition caused by high light intensity. Total chlorophyll (Chl) content increased significantly with increasing shading intensity, whereas the Chl a/b ratio decreased. (2) The LS treatment yielded the highest nitrogen (N), phosphorus (P), and crude protein (CP) contents, along with a more balanced N:P ratio, suggesting a superior state of nutritional metabolism. Growth indicators showed significant positive correlations with WUE and Chl content, and significant negative correlations with transpiration rate (Tr) and Ci, confirming a synergistic “physiological adaptation-growth optimization” mechanism. Our results demonstrate that light shading represents the optimal condition for the growth and biomass accumulation of A. fruticosa, highlighting its potential as a key species for vegetation restoration in PV power stations within arid ecosystems. These findings not only elucidate the plant’s adaptation mechanisms but also provide a crucial physiological basis for selecting and managing understory vegetation, thereby supporting the optimization of integrative “PV-Ecology” systems for sustainable desert restoration.

To explore the regulatory mechanisms of different vegetation types on soil crust grain-size characteristics in sandy lands, this study focused on five typical plant species (Haloxylon ammodendron, Artemisia ordosica, Nitraria tangutorum, Agriophyllum squarrosum, and Phragmites australis) in an artificial vegetation restoration area on the northeastern edge of the Ulan Buh Desert. Using laser granulometry and graphical methods, we systematically determined the soil particle size composition and parameters of the crust (Layer A) and sub-crust (Layer B) layers, and analyzed their correlations with plant morphological parameters (crown width, plant height, basal diameter). The results showed that (1) different vegetation types significantly increased the content of soil fine particulate matter (silt and clay), with fine sand accounting for 42.85% and silt accounting for 23.64%; (2) there are significant differences in the impact of different vegetation types on particle size parameters. The average particle size of soil crust under Phragmites australis is the smallest (1.91), and the sorting is the worst (standard deviation 2.01). Under the vegetation type of Nitraria tangutorum, the average particle size of the soil crust layer is the largest (5.25), and the fractal dimension is the highest (2.46). (3) The crown width, plant height, and basal diameter of vegetation are negatively correlated with mean particle size, kurtosis, and fractal dimension (r= −0.62 to −0.45), and positively correlated with standard deviation and skewness (r = 0.51 to 0.68). (4) The frequency curve indicates that vegetation types broaden the distribution range of soil particles, and Phragmites australis and Artemisia ordosica exhibit bimodal characteristics. This study reveals the impact of vegetation restoration on soil grain size parameters in arid regions. These findings provide actionable strategies for optimizing vegetation configuration in actual desert restoration projects, notably proposing a “herbs first, shrubs follow” approach that can be directly applied to enhance restoration efficiency.