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The implementation of Salix psammophila sand barriers measures constitutes a crucial element in desertification control, providing a solid theoretical foundation for the future application and pretreatment of sand barriers in production practices. To address the specific damage types predominant in desert environments, we executed simulations of ultraviolet irradiation and rainfall phenomena on mechanical sand barriers in sandy areas and also inspected the variations in chemical properties during accelerated aging processes. The findings unequivocally demonstrate that: (1) The synergistic impact of ultraviolet irradiation and water accelerated the deformation and fracturing of the S.psammophila sand barriers, thereby causing a partial degradation of its chemical properties and conspicuous lignin oxidation; (2) The fissure of the sand barrier deepened, resulting in structural alterations. The existence of water expedites the degradation process of S.psammophila sand barriers under ultraviolet irradiation. (3)With respect to the binding form of C atoms, the carbon atoms at S.psammophila sand barriers were highly oxidized after 576 hours of accelerated aging. The components of C2 (C-O) and C3 (C=O) rising to 40.16% and 12.24% respectively, while the components of C1 (C-C) declined to 47.60%. The amount of hydroxyl (O-C-O), carbonyl (C=O), and carboxyl (O-C=O) groups increases in line with the expansion of the contact area between the sand barrier structure and ultraviolet irradiation as well as water. More free radical substances are generated, thereby causing the chemical binding properties to tend to be more stable. In summary, Ultraviolet irradiation and water change are the primary factors influencing the degradation of S.psammophila sand barriers material structure and properties. In future desertification control, it is imperative to focus on enhancing the longevity of sand barriers by ensuring their waterproofing capabilities and resistance to ultraviolet irradiation.

The comprehensive effect of multi-source factors has altered the landscape pattern and ecological processes within the Beijing-Tianjin Sandstorm Source Control Project (BTSSCP) area, resulting in a fragile environment. Scientific evaluation of the landscape ecological risk (LER) in the project area and identification of the drivers of landscape ecological risk are crucial for preventing and resolving ecological risks and protecting the ecosystem in northern China. This study aims to establish an ecological risk assessment framework, analyze the spatiotemporal changes in the LER in the BTSSCP area from 2000 to 2020, evaluate different factors in depth using the Geodetector model, and predict the LER in 2030 under multiple development scenarios using the patch-generating land use model. The results showed that (1) the dominant land use type in the BTSSCP area was grassland, accounting for more than 50 % of the total area, followed by cropland, unused land, and woodland. (2) The average LERI values in the BTSSCP area for 2000, 2010, and 2020 were 0.023, 0.022, and 0.021, respectively. This demonstrates that the LER in the study as a whole was low and steadily declined. (3) The LER in the project area was influenced by multiple factors. Overall, the evolution of the LER in the study area was primarily affected by natural factors, and the amount of interaction among the multiple factors increased over time. Locally, the normalized difference vegetation index and mean annual temperature were both important factors in this area.

Abstract 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.

Inner Mongolia’s grassland is one of the most complete natural grasslands for ecological diversity and biodiversity conservation in the world. However, its degradation has seriously affected the plateau’s sustainable development and grassland restoration and reconstruction. To reveal the response of soil-plant synergistic relationship to different degrees of degradation, we selected three degrees of degradation (total coverage of vegetation:20%–30%, LD), moderate degradation (total coverage of vegetation:10%–20%, MD) and severe degradation (total coverage of vegetation:

To investigate the soil improvement effects of different vegetation restoration measures during the operation and maintenance of photovoltaic power plants in the Hobq Desert. This study determined the soil grain size composition and soil nutrient content of 0–5 cm under four vegetation restoration measures and within the mechanical sand barriers by laser diffraction techniques and chemical experiments. The results showed that: (1) Soil particle size composition in the study area is predominantly sandy, with 1.02%, 6.63%, 5.34% and 2.61% less sand in Leymus chinensis (YC), Glycyrrhiza uralensis (GC), Artemisia ordosica Krasch (YH) and Hedysarum scoparium (HB), respectively, compared to mechanical sand barriers (CK). Soil particle distributions of YC, GC, and HB showed better sorting and more concentrated patterns, and all four vegetation restoration measures had higher fractal dimensions than CK. (2) AN (Alkali-hydrolyzable Nitrogen) content performance: The content of YC, GC, and HB was significantly higher than that of YH and CK, AP (Available Phosphorus) content did not differ significantly between measures, AK (Available Potassium) content was higher than that of CK in all measures, with YC content being the highest and SOM content being the highest for GC. (3) Soil total nutrient is unstable across vegetation restoration measures. Overall, the performance showed that the three vegetation restoration measures, YC, GC, and HB, were more evident in the soil total nutrient content improvement. Each particle size characteristic parameter and soil nutrient response vegetation restoration measures ameliorate sandy soil in PV power plants during operation and maintenance. YC and GC have the most apparent effect on soil amelioration.

In the fragile desert ecosystems of the world, sand-fixing measures play an irreplaceable part in ecological restoration. However, it is unclear how the long-term establishment of sand-fixing measures affects soil particle distribution and soil nutrients for the desert – Yellow River coastal ecotone. Therefore, we selected sand-fixing measures that have been established for fifteen years: Pinus sylvestris (PS), Populus alba (PA), Elaeagnus angustifolia (EA), Hedysarum scoparium (HS), Salix psammophila (SC), Salix psammophila checkerboard barriers (SCSB), and mobile sandy land (LS). We analyzed soil physical properties, chemical properties, soil fractal dimension (D), and multi-fractal parameters in the top soil layer (0–20 cm). The results showed that the establishment of sand-fixing measures significantly increased the clay and silt, and decreased the sand (p

Vegetation plays a leading role in restoring desert ecosystems and increasing productivity. In this study, we elucidate the improvement effects of different restoration areas of Populus alba on the soil particle distribution, sedimentation environment, and fractal characteristics. We selected the restoration areas of P. alba × Caragana korshinskii (YN), P. alba × Hedysarum leave (YY), and P. alba × Hedysarum scoparium (YH), which have a history of twenty-one years. We analyzed the soil nutrients, soil particle size, soil particle size parameters, soil fractal dimension (D) values, and soil multifractal parameters at soil depths of 0–80 cm. We found that the YN, YY, and YH significantly increased the soil nutrients and soil fine particles (p < 0.05) and changed the deposition pattern of the soil particles in the sandy area. The YN, YY, and YH promote soil particle refinement and reduce the sorting performance of the soil particles. The vegetation promotes extremely positive-skewed and very leptokurtic soil particle distributions. The D values in the YN, YY, and YH restoration areas increased by 7.62%–27.94%, 7.36%–26.28%, and 7.10%–17.92%, respectively, relative to those of the LS. The construction of the different restoration areas of P. alba has made the distribution of the soil particles nonuniform. Compared with the YY and YH plantations, the distribution range of the soil particles in the YN plantation is wider, and the distribution heterogeneity is greater. In addition, we found that the fractal parameters are influenced by the soil physicochemical properties, the depositional environment, and vegetation factors. Therefore, we believe that D values and multifractal parameters are necessary as additional information for desert soil texture improvement. The results of this study provide a scientific and theoretical basis for the future revegetation of deserts.

Better understanding the wind regimes and dune activity criteria are pre-requisites for the successful planning of any sand dune fixation project and hence have a high priority. To fully understand wind energy conditions and the intensity of aeolian activity, we investigated the wind conditions, sand-transporting potential, and sand-transporting capacity of the basins of mid-course ten tributaries of the Yellow River through field observations and indoor analyses. 1) The analysis of wind energy, which is based on sand transport potential, demonstrates that there is substantial spatial variation within the study area. The western part, which is located near the Kubuqi Desert, qualifies as a high wind energy zone. In contrast, the central part belongs to the medium wind energy zone, whereas the eastern part is categorized as a low wind energy zone. Even though there are notable differences in the sand transport potential characteristics across different time scales, the direction of the synthesized sand transport potential tends to be consistent, predominantly leaning towards the southeast. This orientation provides the requisite energy for the sand material to be transported into the river. 2) The prevailing sand-producing wind direction at various timescales in the research area was dominated by westward (W, WNW, NW) and northward (NNW, N) winds, with distinct seasonality. This seasonal variability was especially prominent in spring, which saw the highest frequency of aeolian activity and the largest volume of sand transport. Autumn and winter exhibited similar patterns, and, in the summer, it was the lowest 3) The relationship between sand-transporting potential and sand-transporting capacity, which is a crucial aspect of aeolian geomorphology, could be adequately depicted using a fitting function based on the temporal patterns of wind speed. During periods of high wind, the sand-transporting potential and sand-transporting capacity of the basins of the ten tributaries followed a power function relationship. Conversely, during periods of low wind, they followed an exponential function relationship. These results imply that spring should be deemed as the crucial period for wind-sand prevention and control. Additionally, emphasis should be placed on the western part, which is situated close to the sand source area, as the primary prevention and control zone.

To explore how to lay the same specifications to maximize the protection benefits of mechanical sand barriers is an essential issue in the actual production process. We used the Reynolds-Averaged Navier-Stokes (RANS) method and the shear stress transport (SST) K-ε turbulence model to study the windbreak efficiency of sand barriers with different structures. Among them, the structure of the sand barriers includes rhombus 60° (cTnI = 60°, R60°), rhombus 90° (cTnI = 90°, R90°), rhombus 120° (cTnI = 120°, R120°) and parallel straight line (belt). The sand barrier was set to a porous jump model, where the surface permeability a was 2.6 × 108, and the inertial resistance coefficient c2 was 9,400. The wind velocity field results showed that the sand barrier’s blocking effect on wind velocity decreases with the increase in height. The leading edge of the 120° obstacle has the strongest weakening effect on the inlet wind speed. The minimum wind speed (0.97 m/s to 1.41 m/s) occurs near the sand barrier, and the vortex appears on both sides of the node, and the wind speed increases. The order of the blocking effect of different angles on airflow is as follows: 120° > 90°> brand >60°. Under R120° conditions, the wind speed is reduced by more than 60% at 0.05 m and 0.1 m height behind the barrier compared to the initial wind speed. This will be conducive to the design and control engineering planning of the laying angle of the gauze sand barrier in the main wind direction.

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.

Semi-arid playas are important to grassland ecosystem species as an important source of global dust emissions. However, there is a lack of data on dust emissions during the different drying stages of grassland playas. In this study, we initially conducted the field experiments on two types of surfaces (intermittently dried and permanently dried) in playas located in semi-arid regions in northern China, and we measured dust emissions at five wind speeds in spring when wind erosion was frequent. The results showed that the intermittently dried surface was more prone to wind erosion, which was primarily due to the formation of a loose and fragile salt crust on the surface. In addition, the proportion of salt in the dust was higher than that for the permanently dried surfaces. Nevertheless, the total horizontal dust flux (1.13–2.3 g/cm2·min) from the intermittently dried surface was only 5%–15% that of the permanently dried surface (7.47–42.86 g/cm2·min). The dust content varied linearly with the height of the intermittently dried surface, and varied exponentially with the height of the permanently dried surface. The particles collected on the intermittently dried surface were larger (

Soils that contain rock fragments (particles > 2 mm in diameter) are distributed all over the world. The presence of these small rock fragments can have a great impact on soil water retention properties, as well as on the soil-water infiltration and vegetation restoration in semi-arid regions. To quantitatively describe the transport of water in stony soils, repacked soil cores were used to determine the infiltration rates for different rock fragment contents (0%, 10%, 20%, 30%, and 40%) and rock fragment sizes (2-5, 5-8, 8-11, and 2-11 mm). The results showed that both the content and size of the rock fragments and their interaction significantly affected the infiltration process. The infiltration rates over time and the saturated hydraulic conductivity (Ks) decreased with an increasing rock fragment content to an observed minimum value for a 40% rock fragment content. The soil-water infiltration processes were accurately described by the Kostiakov model. The measured and calculated Ks values decreased with an increasing rock fragment content, which was in accordance with the published data and in accordance with the Ks obtained by five empirical methods. The variations in the measured Ks were likely due to the variations in the soil properties caused by the soil sample repacking. The results of this study may improve the understanding of the effects of the rock fragment content and size on the infiltration processes in arid and semi-arid desert steppes.

Boundaries may have important effects on landscape patterns, landscape change mechanisms, and dynamic processes. However, little is known about the dynamic mechanism of patch boundary changes at a fine scale. To elucidate the characteristics of grassland patches at fine scales and to provide a reference for the mechanism of change and development direction of patchy landscapes. In this paper, the patch of different grassland types in Xilingol League was studied by NMDS, RDA, and SEM methods, to analyze the vegetation community and soil characteristics of surface soil and the relationship between them: The changes in soil vegetation community and soil characteristics were completely different among the three grassland types, and the abrupt changes of vegetation index and soil properties were different. Vegetation index mostly ranged from −1 m to 0 m, and soil index mostly ranged from −0.5 m to 1 m. Fine-scale vegetation and soil boundaries are well defined, vegetation boundaries are mostly between −1 and 0 m and soil boundaries are mostly between −0.5–1 m, and soil properties have a clear influence on plant characteristics. The difference in organic matter, nitrogen, and phosphorus content is an important factor affecting the change of patch boundary, the distribution of the RDA results showed that the organic matter, nitrogen and phosphorus contents in all three grasslands explained >70% of the environmental factors. The emergence of annual vegetation involves a process of succession, specifically, the nature of the underlying soil determines the type of plants at the boundary. The dynamic characteristics of the soil-plant mutual-feed mechanism determine the location and variation of patch boundaries to adapt to disturbance states. The results of this study provide insight into how boundaries respond to changes in environmental conditions and drive dynamic changes at the landscape level.

The adventitious roots of desert shrubs respond to a nabkhas soil environment by adjusting their configuration characteristics, but the mechanism of this response and the main influencing factors are still unclear. To illustrate this response pattern, Nitraria tangutorum Bobrov, Sovetsk. in West Ordos National Nature Reserve was studied, and the shrub was divided into three growth stages: the rudimental stage, developing stage, and stabilizing stage. A combination of total root excavation and root tracing was used to investigate their adventitious root morphology. The results show the following: (1) As the shrub grows, the ability to accumulate sand into nabkhas increases. (2) The soil nutrient accumulation capacity increased with shrub growth. The “fertilizer island effect” was formed in the nutrient developing stage and stabilizing stage of nabkhas soil, but the rudimental stage was not formed. (3) The adventitious root architecture of N. tangutorum at different growth stages was all herringbone with a simple branch structure. With the growth in N. tangutorum, the root diameter of each level gradually increased, the branches of the shrub grew gradually complicated, and the range of resource utilization gradually expanded. (4) Redundancy analysis (RDA) results show that soil organic carbon (SOC) was the main factor affecting the adventitious root architecture. The results of this study reveal the adjustments the adventitious root architecture of N. tangutorum make in order to adapt to the stress environment and provide data support for the protection of natural vegetation in West Ordos.

A process of infiltration from the soil surface to form soil water is known as soil infiltration; this is the only way for plants to absorb and use soil water. This process is closely related to nutrient migration, surface runoff, and soil erosion. The objectives of this study were to quantify the effect of typical plant communities on soil infiltration performance, reveal the interaction between soil infiltration rate and soil characteristics and plant roots, and determine the primary influencing elements on the Xilamuren grassland. The ring knife method was used to determine the soil infiltration rate at the 0–30 cm soil layer of six typical vegetation communities. The results indicated that the infiltration rate of the Koeleria macrantha community was highest at the soil depth of 0–5 cm, while that of the Convolvulus ammannii community was lowest, reaching 4.25 mm·min−1 and 0.53 mm·min−1, respectively. The soil infiltration rate of different plant communities gradually declined with the increment of soil depth. The strongest correlations were found between bulk density, total porosity, organic matter, root characteristics, and soil infiltration rate. The bulk density, initial water content, capillary porosity, and clay content were the primary influencing factors acting on soil infiltration in the region. Other factors indirectly impacted the infiltration rate by modifying bulk density, which was a crucial limiting factor determining the infiltration rate in the research region. The study’s findings will give theoretical and practical assistance for the prevention and management of soil deterioration and grassland restoration in this area.

Soil hydrology is an inter-discipline of soil science and hydrology that mainly focuses on interactive pedologic and hydrologic processes and properties [...]

Mixed forests play a key role in the environmental restoration of desert ecosystems and in order to address the improvement of soil properties by different mixed vegetation types. We selected four typical mixed vegetation types (including: Populus alba var. pyramidalis × Caragana korshinskii, P. pyramidalis × Hedysarum mongdicum, P. pyramidalis × Hedysarum scoparium and Hedysarum scoparium × Salix cheilophila) that have been restored for 22 years and the moving sandy land in the transition zone between the desert and the Yellow River in northern China. We compared the differences in soil properties using a total of 45 soil samples from the 0–30 cm soil layer (10 cm units). We found that revegetation had a significant positive effect on fine particles, soil nutrients, soil bulk density (SBD), and soil fractal dimension (D) values. Soil D values under different types of vegetation range from 2.16 to 2.37. Soil nutrients and fractal dimension showed highly significant or stronger negative correlations with SBD and sand and highly significant or stronger positive correlations with clay and silt. The construction of P. pyramidalis × C. korshinskii improved the soil texture better than other vegetation restoration types. Compared to the mobile sandy land, organic carbon (SOC), available phosphorus (AP), available potassium (AK), alkaline hydrolysis nitrogen (AN), total nitrogen (TN), total potassium (TK), clay, and silt increased by 161%, 238%, 139%, 30%, 125%, 69%, 208%, and 441% respectively. As mentioned above, P. pyramidalis × C. korshinskii is a suitable type of mixed vegetation restoration for the area. In addition, establishing vegetation with high nitrogen fixation rates in desert ecosystems tolerant to drought and aeolian conditions is beneficial in reversing the trend of desertification. This research will suggest vegetation building strategies for controlling desertification.

Dry salt lakes are widely distributed in semi-arid regions. Dry lake beds have been found to have a greater capacity to release dust. However, the particle size characteristics of dry lakebed soils have rarely been studied. To reveal the soil grain size characteristics, we used surface and subsurface soil from dry lake beds in semi-arid regions with different soil crusts as the object of study. We used particle size parameters and class-standard deviation methods to study the particle size variation patterns and the degree of variability. The results show that the dry lake was mainly composed of clay (1.36%-43.96%) and silt (5.5%-67.94%) particles. Soil particle characteristics show the Mean size (Mz) of (0.65-8.89 f), poorly sorted (0.79-3.38 f) and a clear linear relationship between dry lake bed skewness and sorting. There is a high variability between soil particle size fractions across the lake bed, with soil crusts and soil moisture protecting the loss of subsurface soil particles, hence the differences between surface and subsurface soil particles. However, the destruction of the soil crust and the evaporation of soil moisture accelerates the wind erosion of the subsurface soil particles. In the dry lake area, vegetation construction has promoted the accumulation of sand content (73.28% -93.08%). We found that the fractions 0.19-9.15 µm, 9.15-36.99 µm, 36.99-366.93 µm, and 366.93-1214.72 µm are susceptible to respond to environmental changes and contribute to dust storms. Therefore, local governments should treat and manage dried-up lakes to reduce the impact of salt dust on the ecosystem. [ABSTRACT FROM AUTHOR]

Playas are one of the major sources of saline and alkaline dust in northern China, which release a large amount of sand and dust material every year, severely impacting the quality of the atmosphere, production and life on the Inner Mongolian Plateau in northern China. The surface characteristics of playa activation processes influence the horizontal salt migration flux, but the salt transmission volume of playas is almost unknown in dry salt lakes in a typical steppe. The functional relationship between horizontal salt dust transmission volume and the grain size content was ascertained for four different surfaces at situ sites in the Chagan Nur playa in northern China. After collecting salt dust from four surfaces (crust, broken crust, activated and sandy saline surface) formed during different stages of the desiccation process, the salt dust transmission was assessed based on the wind velocity profile, grain size, and total wind erosion particulate matter (TWEP) profiles above the playa surfaces. The particle size gradually increased from the center of the lake to the shore, while the water content decreased. The wind speed, friction velocity, and roughness of the four surfaces were as follows: sandy saline surface