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The identification and prediction of potential suitable areas for forest resources in Inner Mongolia based on the maximum entropy (MaxEnt) model are of great significance for the protection and utilization of forest resources and the promotion of sustainable development in the region. This study collected geographical distribution data of 14 dominant tree species, selected 32 environmental variables combined with climatic, topographic, and soil indicators, and used the MaxEnt model to predict potential suitable areas for each tree species under the current and future Shared Socioeconomic Pathway 245 (SSP245) climate scenario. We identified the environmental factors that make the greatest contribution to the distribution of various tree species, and by taking cities as units, we delineated Inner Mongolia, investigating the suitable tree species for different areas. The results are as follows: (1) The accuracy of MaxEnt model was good, and the Area Under the Curve (AUC) > 0.8, Kappa > 0.8, True Skill Statistic (TSS) > 0.7 of each dominant tree species proved that it could effectively simulate the potential suitable area of each tree species. (2) The influence of environmental factors on suitable areas varies with tree species, and compared with terrain and soil indicators, climate indicators exhibit a greater influence. (3) The main suitable tree species in the Western Desert Region are drought-tolerant shrubs. The Central Prairie Region is dominated by arbor-shrub mixed forest. The Eastern Forest Region is mainly suitable for Betula platyphylla, Betula dahurica and so on. (4) In the future climate under the SSP245 scenario, the suitable area for Pinus sylvestris, Populus simonii, Larix gmelinii, and Betula platyphylla would show a decreasing trend, whereas the other 10 tree species would exhibit an increasing trend. Furthermore, the distribution center of the suitable areas for most tree species would move to the west.

IntroductionCreating an ecological space network is essential for safeguarding the core structure of ecological space.MethodsMorphological spatial pattern analysis was used to locate ecological sources in the Kuye River Basin. Using the least cumulative resistance model and gravity model, the resistance surface, ecological corridor, and ecological space management network are determined.Results and discussionThe study revealed that in 2022, the predominant land use types in the Kuye River Basin were wood land and grassland, cultivated land, and construction land. MSPA model software identifies a substantial portion of the landscape pattern as consisting of core and marginal areas, which encompass 30324.05 hm2 and 15088.24 hm2. High ecological resistance surface factors dominate the socioeconomically vibrant zone and northern regions. Resistance values ranging from 0.02 to 0.87, and high and law resistance zones alternate. The minimal cumulative resistance approach found 171 ecological corridors. And gravity model using the interaction matrix of 19 primary ecological sources discovered 8 first-level ecological corridors with the highest interaction force. There are 137 core and 23 subsidiary ecological corridors with significant affects. Overlying the road factors and ecological corridors of national highways, provincial roads, railways, and high-speed roads creates a total of 38 ecological breakpoints, each characterized by specific barrier effects and legal ecological stability.

Larix gmelinii is an important ecological construction tree species in northern China, and its carbon storage and distribution characteristics are of great significance for evaluating the carbon balance and climate effect of forest ecosystems. However, at present, there is a lack of systematic research on the carbon storage of L. gmelinii forests and its change with forest age. In this paper, the biomass and carbon density of L. gmelinii forests at different ages and the distribution of carbon storage in vegetation and soil were analyzed by means of sample plot investigation and model simulation in the northern forest area of Daxing’anling, Inner Mongolia. The influence of forest age on the carbon storage and carbon pool distribution characteristics of L. gmelinii forests and the mechanism of influencing factors were also discussed. Results show that: (1) As forest age increased, the total amount of carbon pools initially increased and then decreased, and the distribution structure of carbon pools showed a trend of transferring from soil to trees. The proportion of soil carbon pools gradually decreased (72.72–51.87%), while the proportion of tree carbon pools gradually increased (23.98–39.33%). The proportion of shrub and grass carbon pools was also relatively stable (0.51–0.53%). (2) Soil carbon pool was affected by the input and output of soil organic matter, soil depth, soil carbon content, and soil bulk density, shrub–grass carbon pool was affected by undergrowth light conditions and soil moisture, litter carbon pool was affected by litter input and output, and the carbon pool of trees was affected by the growth rate and carbon balance of trees. This study provides scientific basis and management suggestions for the carbon storage capacity of L. gmelinii forests and the mitigation of climate change.

The Pisha Sandstone is widely exposed in the northeastern margin of the Ordos basin. Since the Mesozoic the basin was subjected to uneven uplift several times, strong weathering and erosion have been occurring and a large amount of sediments derived from these erosional strata are input into the lower Yellow River, posing a fragile ecological environment along the river. However, the geochemical characteristics of the Pisha Sandstone have remained poorly understood. In this study, we focus on the Pisha Sandstone from Early–Middle Triassic Liujiagou, Heshanggou and Ermaying Formation, present a very first petrographic and geochemical data together with detailed field geological characteristics, aiming to place geochemical indicators on weathering, provenance and tectonic setting of the Pisha Sandstone. The results show that sandstones in Pisha Sandstone are classified as arkose, litharenite and wacke. The geochemical proxies including Chemical Index of Alteration (CIA = 67.2), Chemical Index of Weathering (CIW = 80.1), Plagioclase Index of Alteration (PIA = 75.6) and Index of Compositional Variability (ICV = 1.6) indicate Pisha Sandstone experienced first–cycle deposit and moderate to strong chemical weathering. Trace element and rare earth element concentrations together with their ratios (La/Sc, La/Co, Th/Sc, Th/Co, Cr/Th) reveal a felsic provenance, and source rock compositions are predominantly granodiorite and granite from the north margin of the Inner Mongolia Paleo–Uplift (IMPU), with a small amount of mafic or intermediate components. The geochemical signatures and tectonic discrimination diagrams display a collision setting for the Pisha Sandstone and further reveal the sediments had been deposited in a continental island arc setting. The results of this work may provide new theoretical basis for environmental protection in the Pisha Sandstone area.

Land cover change influences the provision of regional ecosystem services, posing a threat to regional ecological security and sustainable development. The Kuye River Basin, a vital tributary of the Yellow River Basin, has experienced significant land cover changes due to intense human activity. Building on analysing the spatiotemporal evolution of land use cover and ecosystem service values from 1990 to 2022, this study predicted the land cover structure and ecosystem service value with two future scenarios, the NDC and the EPC, to provide insights into guiding sustainable policy interventions. We found the predominant land cover types were greensward and forest land, accounting for 67.22% of the total area. Forest land, greensward, and farmland have increased, while desert, water area, and other land types have decreased from 1990 to 2022. Forest land, greensward, farmland, and water areas are the main contributors to ecosystem service value in the Kuye River Basin. However, water area services have significantly decreased from 1990 to 2022. Under the NDC scenario, land development primarily relies on greensward and farmland, reducing forest and water areas and weakening the ecosystem’s regulatory and supporting functions. In contrast, the EPC scenario enhances ecosystem services by protecting critical ecological regions. Ecological protection measures significantly increase the ecosystem service values of the Kuye River Basin, and well-planned land use can effectively balance economic development with ecological preservation. This study provides scientific evidence to inform policies integrating ecological protection and economic growth, contributing to the sustainable development of the Kuye River Basin.

As global ecological degradation intensifies, the long-term impacts of afforestation on productivity and soil fertility in barren lands have become critical in improving global ecological security and productivity. Through meta-analysis, this study integrates data from 109 barren land afforestation sites across China, aiming to comprehensively analyze the effects on plant productivity and soil fertility while identifying the key environmental drivers of these changes. We found that afforestation consistently enhances plant productivity across 60 years. However, soil fertility and moisture initially surged significantly after afforestation but gradually declined after the first decade, indicating the limited long-term benefits. Climatic factors, namely precipitation and humidity index, are crucial in enhancing plant productivity, while geographic factors, specifically lower elevations and gentler slopes, are associated with greater increases in soil fertility. Elevation and slope are two key factors that influence soil moisture after afforestation. These findings highlight the need for ongoing soil management and ecological maintenance in afforestation projects to sustain the soil fertility benefits. Our study provides a robust scientific foundation for afforestation strategies aimed at barren land restoration and offers valuable insights for policy formulation in barren land afforestation.

The Genhe River Basin is an ecological barrier and water conservation area in northern China, but its hydrological process has undergone significant changes due to climate change and human activities, endangering ecosystem functions and water resource security. Systematic research on the influencing mechanisms and laws of hydrological processes in different ecosystems in this region remains lacking. Therefore, this study analyzed the effects of different anthropogenic factors on the hydrological processes of typical ecosystems in the Genhe River Basin. The Soil and Water Assessment Tool distributed hydrological model was used to simulate the surface runoff, evapotranspiration, and soil water content of the three ecosystems of forest, grassland, and farmland in four different periods of 1980, 1990, 2000, and 2010. The spatial and temporal changes in water resources in typical ecosystems under the influence of historical climate change were demonstrated. Results showed that under different land use scenarios, the surface runoff of the farmland ecosystem increased, the evapotranspiration remained unchanged, and the soil water content decreased. The surface runoff of forest and grassland ecosystems did not change significantly, the evapotranspiration increased, and the soil water content decreased. This study reveals the influence of different human factors on the hydrological processes of typical ecosystems in the Genhe River Basin and provides a scientific basis for water resources management and ecological protection in the region.

[Objective] The relationship between land use change and ecological process in the ten tributaries area in Inner Mongolia was studied to reveal the relationship between human activities, land use, and ecological environment in order to provide a basis for the optimization of land use structure and regional ecological environment protection. [Methods] Landsat images from 2000 to 2020 were selected. Land use data and transfer matrices in different periods were obtained by using the method of supervised classification combined with a land statistical module. The dynamic change of land use and the comprehensive index of land use degree were analyzed. On this basis, the NDVI value, ecological environment quality index, and other indicators were selected by using mathematical statistics and other methods to comprehensively evaluate the ecological environment quality of the ten tributaries. [Results] ① During the 20 years of the study period, the proportion of forest land and grassland area changed the most, and the proportion of water area was the smallest, with frequent transitions between land use types, An obvious "upward trend" for forest land and an obvious "downward trend" for grassland and unused land were observed; ② The ecological environment quality indexes of the transformation of land use types in 2000, 2010, and 2020 in the ten tributaries were 0.526 1, 0.537 3 and 0.543 3, showing an overall upward trend. In terms of spatial distribution, the ecological environment quality was high in the east and low in the west, and high in the south and low in the north; ③ The annual average precipitation and annual average wind speed had significant positive impacts on the ecological environment quality. The annual average temperature had a significant negative impact on the ecological environment quality. [Conclusion] With the rapid development of urbanization occurring from 2000 to 2020, the ecological environment quality of the ten tributaries has also developed in a good direction. The ecological environment quality in the study area has improved overall and deteriorated locally. The transformation between construction land, forest land, grassland, and unused land is the main reason for changes in ecological environment quality. Environmental protection policies such as returning farmland to forest have continuously improved the environmental quality of the study area.

Monitoring the dynamics of bacteria in porous media is of great significance to understand the bacterial transport and the interplay between bacteria and environmental factors. In this study, we reported a non-invasive, real-time, and efficient method to quantify bioluminescent bacterial concentration in water and sand media during flow-through experiments. First, 27 column experiments were conducted, and the bacterial transport was monitored using a real-time bioluminescent imaging system. Next, we quantified the bacterial concentration in water and sand media using two methods—viable count and bioluminescent count. The principle of the bioluminescent count in sand media was, for a given bioluminescence image, the total number of bacteria was proportionally allocated to each segment according to its bioluminescence intensity. We then compared the bacterial concentration for the two methods and found a good linear correlation between the bioluminescent count and viable count. Finally, the effects of porous media surface coating, pore water velocity, and ionic strength on the bioluminescent count in sand media were investigated, and the results showed that the bioluminescence counting accuracy was most affected by surface coating, followed by ionic strength, and was hardly affected by pore water velocity. Overall, the study proved that the bioluminescent count was a reliable method to quantify bacterial concentration in water (106 to 2 × 108 cell mL−1) or sand media (5 × 106-5 × 108 cell cm−3). This approach also offers a new way of thinking for in situ bacterial enumeration in two-dimensional devices such as 2D flow cells, microfluidic devices, and rhizoboxes.

Since 2000, the Chinese government has implemented a series of ecological restoration policies to combat ecological degradation and land desertification in drylands. However, it remains unclear whether ecosystem services (ES) in drylands have improved since then. To this end, we analyzed the long-term trends (2000–2020) of four ES (NPP, sandstorm prevention, soil retention, and water retention) and the associated drivers in the Hunshandak sandy land of Inner Mongolia by using multi-scale trend analysis. We found that: (1) all the four ES types, including NPP, soil retention, sand prevention, and water retention showed increasing trends, with Zhenglan banner and Kashiketeng banner showing the most significant growth. (2) The changes in ES showed significant spatial heterogeneity, with 54%, 18%, and 53% of the total area still being degraded for NPP, sandstorm prevention, soil retention, and water retention, respectively. The degradation hotspots of ES are mainly located in Sunit Left Banner, Sunit Right Banner, Zhengxiangbai Banner, and Duolun County. (3) Both the conversion of sandy land into grassland due to ecological policies and the improvement of climatic conditions contributed to the enhancement of ES in this region. Our results indicate that ecological restoration policies have improved ES in the Hunshandak Sandy Land, but the effects of the policies show regional unevenness. Future ecological restoration policies should pay more attention to areas with a decreasing trend of ES and to the problem of overgrazing in fragile pastoral areas.

Background This study was aimed to explore the compensatory growth ability and influence mechanism of Hippophae rhamnoides at the decaying phase in feldspathic sandstone areas of Ordos, and clarify the stubble height when the compensatory growth ability of H. rhamnoides was the strongest. Methods The H. rhamnoides forests in the decaying phase from an exposed feldspathic sandstone zone of Ordos were chosen. The compensatory growth ability of H. rhamnoides at stubble height of 0 cm (S1), 10 cm (S2), 15 cm (S3), 20 cm (S4) and control (CK) was investigated with H. rhamnoides forests at the decaying stage in the exposed feldspathic sandstone areas of Ordos. Relationships of compensatory growth ability of H. rhamnoides and understory soil properties with understory soil stoichiometric features as well as the response mechanism to stubble height were explored. Results (1) Overcompensatory growth of H. rhamnoides in feldspathic sandstone areas occurred at all stubble heights. Especially, the plant height compensation index (1.45) and biomass compensation index (1.25) at the stubble height of 15 cm were both larger compared with other stubbling treatments. These results indicate the stubble height of 15 cm can well promote the growth of the ground part of H. rhamnoides. (2) All stubble heights significantly affected the contents and eco-stoichiometric ratios of soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP) in understory soils, but the influence rules differed. SOC, TN, and TP contents at all stubble heights were larger than those of the control, and maximized at the stubble height of 15 cm. The carbon(C): phosphorus(P) ratio, and nitrogen (N):(P) ratio after stubbling treatments were all lower compared with the control, and minimized to 19.52 and 1.84 respectively at the stubble height of 15 cm. (3) The understory C:N:P stoichiometric ratio of H. rhamnoides in feldspathic sandstone areas is jointly affected by compensatory growth, stubble height, and soil physicochemical properties. The total explanation rate determined from RDA is 93.1%. The understory soil eco-stoichiometric ratio of H. rhamnoides is mainly affected by soil moisture content (contribution of 87.6%) and total porosity (7.9%), indicating soil moisture content is the most influential factor. The findings will offer some new clues for eco-construction and theoretically underlie soil-water loss administration.

Located in the middle and upper parts of the Yellow River Basin, Qingshuihe County, Inner Mongolia, is a typical hilly and gully loess region and one of areas under the implementation of major ecological protection and restoration projects in the key ecological areas of Yellow River. Scientifically and accurately constructing a soil quality evaluation system for different types of artificial forest land and evaluating their soil quality are essential because they help optimize the structure of artificial forest land and improve the soil quality in the loess hilly area of Yellow River Basin. In this study, soil from four representative types of artificial forest land in the middle and upper reaches of the Yellow River Basin in Inner Mongolia was selected as the study object, with natural non-forest land as the control. Sixteen soil property indices in five classes, namely, soil texture, acid–base properties, moisture, pore, and nutrient, were screened using correlation analysis, minimum dataset (MDS), and principal component analysis methods, and an MDS of soil quality evaluation was constructed. Results showed that (1) the evaluation indices of artificial forest land soil quality based on the MDS included total potassium content, total phosphorus content, alkali-hydrolyzed nitrogen content, total nitrogen content, sand content, moisture content, and non-capillary porosity. (2) No significant differences were observed in the soil quality index among the MDS, total dataset, and significant dataset (SDS), all of which exhibited significant positive correlations. (3) The soil quality of the different types of forest land was sorted from high to low as follows: mixed coniferous and broad-leaved forests, larch forests, mixed arbor and shrub forests, Armeniaca sibirica forests, and natural non-forest land.

Research on the infiltration characteristics of surface water is fundamental for understanding the entire hydrological process. Therefore, studying the water infiltration process of sandstone slopes overlaid with loess and predicting soil moisture content are of great importance for investigating hydrological processes and controlling soil erosion in the hilly and gully areas of the Loess Plateau in China. This study mainly focuses on the simulation of the vertical water infiltration characteristics and water movement patterns of four kinds of sandstone (feldspathic and argillaceous sandstone) structures covered with thin layers of loess. In the one-dimensional vertical infiltration experiment and Hydrus-1D model simulation, the interlayer transition planes of loess–feldspathic and loess–feldspathic–argillaceous sandstones were found to present two conditions: fine soil covering coarse soil and coarse soil covering fine soil. Therefore, water infiltration reduced permeability. The existence of a transition layer between loess and feldspathic sandstone decreased the water infiltration rate and infiltration amount and decelerated the speed of the wetting front, thereby further affecting the ability of water infiltration. By using the Hydrus-1D model, 15 sets of soil hydraulic parameters, including θx (0.028–0.05795 cm3/cm3), θs (0.2306–0.4786 cm3/cm3), α (0.01899–0.06071 cm−1), n (1.438–6.408), and Ks (1.96·10−4–0.0576 cm/s) were inverted and optimized for each 20 cm soil layer (total of 60 cm). The Van Genuchten model constructed using these parameters demonstrated high accuracy in the simulation of water content in the vertical infiltration process of sandstone covered by loess with the coefficient of determination R2 > 0.849 and relative error RE < 5.311.

[Objectives] To explore the niche characteristics of herbaceous plants under Pinus tabuliformis plantation forest in the feldspathic sandstone area, and to provide basic data for maintaining biodiversity and community stability in the local P. tabuliformis plantation forest. [Methods] The types, quantity, average plant height, and coverage of various herbaceous plants were recorded by field survey in a well-growing P. tabulaeformis forest area. Based on the survey data, Shannon and Levins niche breadth index, Levins niche overlap index and ecological response were used to analyze the niche characteristics of herbaceous plants under P. tabulaeformis plantation forest. [Results] (i) There were 35 species of herbaceous plants in the P. tabulaeformis plantation forest in the feldspathic sandstone area. Among them, Stipa bungeiensis had the largest niche breadth indexes with better performance. Because of its strong adaptability, its community was in an obviously advantageous position, (ii) The overall niche width and niche overlap index were generally not high, and understory herb species showed differentiation. (iii) Among the understory herbaceous species, 37.15% of the species were developed species, and 62.86% of the species were declining species. Among the 14 dominant species, 11 were developmental species. The species with largest the resource occupancy were S. bungeiensis (0.188 5), Heteropappus altaicus (0.053 1), and Cleistogenes squarrosa (0.037 9). [Conclusions] Competition among under herbaceous plants in P. tabulaeformis plantation forest in the feldspathic sandstone area was weak, and the community species had poor utilization of resources and environment. Most of the dominant herbaceous species were in the developing stage, indicating that the P. tabulaeformis plantation community tends to be relatively stable at the current stage. [ABSTRACT FROM AUTHOR]

The effects of different nano Fe2O3 dose on water movement, solute transport as well as metal adsorption are studied. The main results showed that: nano Fe2O3 inhibited the process of soil water infiltration and the infiltration rate decreased with the increase of nano Fe2O3 dose. Nano Fe2O3 can improve the water-holding capacity of soil, while under the same soil water suction, soil water contents and the inlet suction increased with the increase of nano Fe2O3 contents, but the shape parameter decreased. Nano Fe2O3 improved soil solute holding ability effectively; with the increase of nano Fe2O3 dose, initial penetration time and the dispersivity increased, but the breakthrough time prolonged. [ABSTRACT FROM AUTHOR]