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In desert areas, the process of mobile sandy land changing to semi‐fixed sandy land and eventually to fixed sandy land after undergoing vegetation restoration is inevitable. The presence of shrub patches and herb patches is common in this restoration process. No relevant studies have reported the soil bacterial community characteristics of different vegetation‐type patches (shrub patches and herb patches) under different stages of restoration. Therefore, we utilized long‐established experimental plots to collect soil from 0–20 cm soil layer under shrub patches (dominated by Salix psammophila) and herb patches under different stages of restoration (i.e., mobile sand land, semi‐fixed sand land, and fixed sand land), by determining soil physicochemical properties, enzyme activities, and soil bacterial communities. Our results found that soil bacterial α‐diversity under different restoration stages showed higher shrub patches than herb patches. The dominant bacterial communities (phyla) in shrub patches and herb patches at different recovery stages were Actinobacteria, Proteobacteria, and Bacteroidota. When the mobile sandy land returned to fixed sandy land, the relative abundance of Actinobacteria and Bacteroidota gradually decreased under shrub patches and herb patches, while the relative abundance of Proteobacteria increased significantly. In addition, herb patches significantly increased the relative abundance of bacteria (genus) relative to shrub patches at different stages of recovery. Soil nutrients, soil fine particles, and soil enzyme activities were significantly higher under shrub patches than under herb patches when fixed sandy land due to differences in life form and architecture between shrub patches and herb patches. Based on this, soil bacterial community composition and diversity under shrub patches were driven by more soil properties during the restoration of sandy land. This study complements the dynamic recovery processes and driving mechanisms of soil bacterial community structure under different vegetation patches in sandy areas, especially in the context of global climate change. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the typical surface wind erosion process of the dry lake basin and the mechanism of the formation of saline-alkali dust storm. [Methods] Taking the Chagannaoer dry salt lake in Abaga Banner of Xilin Gol League as the research object, four different surface types (crust surface, broken surface, activated surface and desertification surface) were selected according to the dynamic evolution process of salt lake surface from the lake center to the lake shore. The characteristics of soil particle size distribution, wind speed profile and sediment transport law near the surface from the lake center to the lake shore were analyzed. [Results] (1) Extending from the center of the lake to the shore of the lake, the grain size of 0-2 cm sediment on the surface showed a trend of gradually thickening, and the clay and silt were the main particles. (2) The wind speed from the center of the dry salt lake to the shore of the lake showed a decreasing trend. Wind speed profiles of different surfaces generally followed the logarithmic distribution of Karman's velocity, and the fitting effect was good (R²>0.90). (3) The amount of sediment transport on the broken surface was the highest, which was about 50 times that of the crust surface, and the sediment transport rate on the crust surface showed a linear law with the change of height due to limited dust supply (R² =0.80), and the sediment transport rate on the other three surfaces showed an exponential function with he change of height (R²>0.97). (4) Near the surface at a height of 0 to 50 cm, the average particle size of and particles carried in the wind-sand flow ranges from 2 to 8 m, which falled under the category of silt, with poor sorting. Skewness was predominantly negative, while kurtosis was mainly medium and sharp. [Conclusion] On the whole, the wind erosion effect on the broken surface was the strongest, and the wind erosion effect on the crust surface was the weakest. The wind erosion effect in this area can be weakened by increasing the critical starting wind speed threshold of sand particles and the coverage of underlying surface. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of plant protection measures on the improvement of the soil in semi-arid wind-sand grassland area, the plant protection system of Chagannur Salt Lake was used as the research object, and the physical and chemical properties of the soil in different areas were measured by the method of field investigation combined with indoor experiment, and the changes of soil salinity, soil pH, soil particle size composition, soil organic matter and nitrogen, phosphorus and potassium content in 0-30 cm depth were analyzed. The results showed that,20 years after the construction of the plant protection system in Chagannur Salt Lake, the initial highly saline and alkaline soil environment had changed significantly under the synergistic effect of the protection zone to block wind erosion materials and plants to improve the soil. Compared with the dried lake center, the pH of each site in the plant protection system decreased to different degrees, and the soil salinity in the alkaline shield decreased by 75.34%; the clay and powder content of the soil in the alkaline shield increased significantly, increasing by 51.60% and 22.14% respectively compared with the dried lake center, and the coarse sand content decreased by 72.06% compared with the dried lake center.The contents of quick-acting potassium, quick-acting phosphorus and organic matter of the soil in the alkaline shield were the highest, which were 86%, 39% and 55% of the dry lake center, respectively. The quick-acting nitrogen content of white thorn bushes in the transition zone was the highest, which was 28% of the dry lake center. Overall each nutrient content showed a significant correlation (P<0.05) with clay and powder grains. After 20 years of construction, the content of quick-acting potassium, quick-acting phosphorus and organic matter of the soil in the alkali plant protection zone had increased significantly compared with that at the beginning of the construction period, indicating that the plant protection system has a significant improvement effect on the soil. The research results could provide data support for the evaluation of the protective effect of the plant protection system in the salt lake, and could provide scientific basis for the control of wind erosion and regional vegetation restoration and reconstruction of the dry salt lake in the semi-arid sandy steppe area. [ABSTRACT FROM AUTHOR]

In order to explore the effects of plant measures on soil physical and chemical properties of photovoltaic (PV) power station in desert, soil grain size, bulk density, porosity and nutrient indexes were determined with sample plots planted Leymus chinensis, Glycyrrhiza uralensis, Artemisia ordosica, Hedysarum scoparium and sand barrier in the power station, respectively. The results showed that the granularity content of fine sand, medium sand and extremely fine sand in the study area was over 90%, among them, the content of components <0.25 mm in Leymus chinensis measure was the highest. The soil bulk density of 0--30 cm layer ranged from 1.47 to 1.67 g·cm-3, and the capillary porosity was 14.53%~31.52%. The soil structure of sand barrier was the best. In 0--30 cm soil layer, the contents of alkali-hydrolyzable nitrogen and available potassium in Leymus chinensis, organic matter in Glycyrrhiza uralensis Fisch and available phosphorus in Hedysarum scoparium were the highest. The research results could provide theoretical basis for ecological protection and restoration of desert PV power stations. [ABSTRACT FROM AUTHOR]

As part of the ecological barrier and an essential element of food security, the agro-pastoral ecotone is vital in northern China. Since soil fertility in northern China is low due to frequent surface disturbances, it is necessary to improve the properties of the soil. This study aims to examine the impact of fungal residue return on soil properties based on six treatments (CK: 0 kg/40 m2; R3: 90 kg/40 m2; R5: 150 kg/40 m2; R7: 210 kg/40 m2; R9: 270 kg/40 m2; R11: 330 kg/40 m2;) of fungal residue return concentration experimental data from 0 to 30 cm soil depth. The results showed that the effect of fungal residue returning on soil habits was greater at 0–10 cm of the surface layer. The bulk density can be reduced to 25.83% of CK, and water content can be increased up to 26.26%. Adding fungal residue to the field led to a greater increase in soil parameters (SOM and AP), and this characteristic effect continued as the return concentration increased. The number of soil bacteria and actinomycetes remained stable, and the amount of fungi was at its lowest. Compared with CK, the number of bacteria, fungi, and actinomycetes increased by 1.94 times, 1.46 times, and 1.71 times, respectively. After the residue was returned to the field, AK had the strongest correlation with other factors (p < 0.01), and microorganism and enzyme activities were strongly correlated (p < 0.01). In conclusion, this study presents a new method of resource utilization of downstream wastes in the food industry while simultaneously providing natural, pollution-free improvements to the soil, which is very beneficial to increasing crop yield. [ABSTRACT FROM AUTHOR]