Search Results (85)

Oasis regions in arid northwestern China represent critical interfaces for watershed ecological security and rural sustainable development. However, under escalating resource constraints and intensifying human–land conflicts, the disorderly expansion of rural settlements has increasingly constrained high-quality territorial development. Liangzhou District, located in the transitional zone of the upper Heihe River Basin at the eastern end of the Hexi Corridor, provides a representative case for examining the spatial evolution of rural settlements in oasis environments. Using multi-temporal land-use data from 2000 to 2023, this study integrates landscape pattern metrics, kernel density estimation, and nearest-neighbor analysis to characterize the spatiotemporal evolution of rural settlements. The Markov–CLUE-S model is further applied to simulate land-use changes under three scenarios for 2035: natural development, new urbanization, and ecological protection. Results indicate that the number of rural settlement patches increased from 1598 to 3009, while their total area expanded from 10,321.83 hm² to 20,828.34 hm², demonstrating a sustained expansion trend and a transition from scattered distribution to increasingly clustered patterns along urban centers and major transportation corridors. Scenario simulations suggest that rural settlement areas will decline by 5.27 km², 12.13 km², and 11.68 km² under the three respective scenarios, predominantly converting to cropland, grassland, and urban construction land. Model validation yields a Kappa coefficient of 0.88, confirming high simulation accuracy. This study develops an integrated “pattern evolution–driving mechanism–scenario response” analytical framework for rural settlement dynamics in arid oasis regions, highlighting the combined influences of environmental constraints and socio-economic drivers. The findings provide a scientific basis for rural spatial optimization and watershed-scale territorial governance in arid regions. Full article

The coordination of agricultural water use efficiency (AWUE) and the level of agricultural economic development (AEDL) is crucial for promoting high-quality development in the Qilian Mountains region. This study was aimed at examining the synergistic development trends and spatial distribution characteristics of AWUE and AEDL. This study focused on 11 cities (autonomous prefectures) within and adjacent to the Qilian Mountains region, employing the Super-SBM model and a comprehensive evaluation model to measure AWUE and AEDL. The coupling coordination degree model and coefficient of variation method were used to analyze the level of development coordination as well as spatial differences. The findings indicate that (1) from 2010 to 2022, both AWUE and the AEDL in these areas showed a significant upward trend, with AWUE increasing from 0.379 to 0.924 and AEDL rising from 0.284 to 0.437. The spatial analysis reveals a pattern of high values in the northeast and low values in other regions; (2) the coupling degree (CD) between AWUE and AEDL is in the primary coupling stage (0.456–0.474), with the coupling coordination degree (CCD) transitioning from low (0.401) to high coordination (0.554) between 2010 and 2022. The spatial distribution characteristics of the CD and CCD are high in the middle section and low in the eastern and western sections. Furthermore, the high coordination area exhibits a spreading evolutionary trend, from Zhangye City to Hexi Corridor regions, from the middle to the east and west sections, and from the north to the south section. These findings suggest that the coupling and coordination between AWUE and AEDL in the Qilian Mountains region have been improved, reaching a higher level. Combined with targeted suggestions, the findings offer valuable insights for designing targeted policies and water-saving measures to advance sustainable agricultural development in arid areas. Full article

Air pollution, particularly fine particulate matter (PM_2.5) and ozone (O₃) pollution, poses serious challenges to environmental quality and sustainable development. The Tibetan Plateau, often described as the “Third Pole,” functions as a key ecological shield for China and exerts wide-reaching influence on global climate systems, hydrological cycles, and cross-regional pollution transport. To better clarify the driving mechanisms of air pollution in this sensitive region, we propose an integrated MRG–HSW framework, which, for the first time, systematically couples statistical modeling and trajectory analysis by combining multivariate regression, residual-based screening, and HYSPLIT–WCWT trajectory analyses. Taking Qinghai Province as a case study, ERA5 and GDAS1 reanalysis products were coupled with in situ monitoring to identify the relative contributions of local emissions and long-range atmospheric transport. The results show that, in low-elevation zones, PM_2.5 levels are largely governed by local anthropogenic activities (R² = 0.631–0.803), whereas O₃ concentrations respond more strongly to meteorological variability (R² = 0.529–0.779). At higher elevations, however, local explanatory factors weaken, and long-range transport from the Hexi Corridor, Qaidam Basin, and even South Asia becomes the dominant influence for both pollutants. Additional sensitivity tests confirm that the framework performs robustly under diverse meteorological and seasonal conditions. Collectively, this work not only establishes a transferable methodology for source attribution in plateau environments but also underscores the pivotal role of the Tibetan Plateau in sustaining regional air quality and global environmental stability. Full article

Since the reform and opening-up, China’s urbanization has progressed rapidly, leading to a continuous migration of rural populations to urban areas. This population outflow is particularly pronounced in the economically less developed Northwest China, triggering a series of issues such as rural vacancy and the idling of residential resources. Against this backdrop, there is an urgent need for scientific methods to guide the renewal design of rural residences, aiming to enhance living comfort, optimize spatial utilization efficiency, and curb rural decline. Although existing research often explores resource utilization strategies at the village level, systematic studies focusing on the individual building scale remain relatively scarce. This study targets rural residences in the Hexi Corridor region. It systematically identifies the “Seasonal Room Rotation” living pattern formed under the context of population contraction and analyzes the “conflict between solar gain and overheating” phenomenon caused by the extreme climate. By integrating architectural characteristics and psychrometric chart analysis, suitable passive design strategies are summarized. Furthermore, based on objectives for indoor light environment and thermal comfort, a genetic algorithm is employed to conduct multi-objective optimization of various building parameters. The results indicate an inherent contradiction in achieving both “warm in winter and cool in summer” within a single room. However, by functionally differentiating building spaces according to their season of use—designating separate “Winter Rooms” and “Summer Rooms”—both winter thermal insulation and summer cooling performance can be systematically enhanced. The research further proposes key design parameters applicable to this new “Seasonal Room Rotation” living pattern, including courtyard form, building height, window-to-wall ratio, and shading component dimensions. This elevates the seasonal adaptation strategy from an internal room-level compromise to a holistic building-level allocation of spatial resources. This study constructs a design methodology for enhancing the green performance of rural residences amidst population contraction. It simultaneously optimizes indoor comfort and spatial utilization efficiency, offering a highly operable new design paradigm for the green renewal of rural homes in complex climatic conditions. Full article

The fragile ecosystem of desert and desertification-prone regions (D & DPRs) in China is highly sensitive to climate change, landuse intensification, and human interventions such as deforestation and overgrazing. In response, large-scale ecological restoration programs have been implemented over the past decades, yet their effect and cost-effectiveness remain insufficiently understood. Here, by applying multi-source remote sensing data, employing the Geodetector model, and developing a Return on Investment (RI) index, we established a framework to quantify the ecological restoration effect and assess the cost-effectiveness of the ecological restoration programs launched in China’s D & DPRs. The results indicated that a marked shift in ecosystem dynamics occurred in 1999. A comparison of the pre-restoration (1982–1998) and post-restoration (1999–2020) periods revealed that the restoration and degradation occur simultaneously, with the proportions increasing by 15.5% and 21%, respectively. Spatially, the identified ecological restoration effect was concentrated in the northern Loess Plateau, the northeastern Inner Mongolia Plateau, and the Hexi Corridor, which were strongly linked to population, land management strategies and infrastructural accessibility. However, the cost-effectiveness analysis revealed that higher levels of ecological investment did not necessarily lead to greater ecological restoration effect. Instead, restoration efficiency varied substantially across different ecological and socio-economic contexts. These findings suggest that ecological restoration in China’s D & DPRs is not a uniform process but is contingent on social-ecological characteristics and investment strategies. Our results emphasize the need for adaptive, region-specific approaches to optimize restoration efforts and ensure the sustainable management of China’s D & DPRs. Full article

As a critical ecological barrier in the arid and semi-arid regions of northwestern China, the spatio-temporal evolution of vegetation carbon sequestration in the Hexi Corridor is of great significance to the ecological security of this region. Based on multi-source remote sensing and meteorological data, this study integrated second-order partial correlation analysis, ridge regression, and other methods to reveal the spatio-temporal evolution patterns of Gross Primary Productivity (GPP) in the Hexi Corridor from 2003 to 2022, as well as the response characteristics of GPP to air temperature, precipitation, and Vapor Pressure Deficit (VPD). From 2003 to 2022, GPP in the Hexi Corridor showed an overall increasing trend, the spatial distribution of GPP showed a pattern of being higher in the east and lower in the west. In the central oasis region, intensive irrigation agriculture supported consistently high GPP values with sustained growth. Elevated air temperatures extended the growing season, further promoting GPP growth. Due to irrigation and sufficient soil moisture, the contributions of precipitation and VPD were relatively low. In contrast, desert and high-altitude permafrost areas, constrained by water and heat limitations, exhibited consistently low GPP values, which further declined due to climate fluctuations. In desert regions, high air temperatures intensified evaporation, suppressing GPP, while precipitation and VPD played more significant roles. This study provides a detailed analysis of the spatio-temporal change patterns of GPP in the Hexi Corridor and its response to climatic factors. In the future, the Hexi Corridor needs to adopt dual approaches of natural restoration and precise regulation, coordinate ecological security, food security, and economic development, and provide a scientific paradigm for carbon neutrality and ecological barrier construction in arid areas of Northwest China. Full article

Water conservation, as a critical ecosystem service, plays a vital role in maintaining regional water resources balance. Against the backdrop of rapid urbanization, the expansion of construction land has intensified the encroachment on ecological spaces, posing significant challenges to water resource carrying capacity. From a supply–demand perspective, this study employs the InVEST model and integrates multi-source data including meteorological and socio-economic datasets to construct models of water conservation supply and demand. Furthermore, spatial analysis methods are applied to examine the evolution of water resource carrying capacity in Gansu Province—a key region within the Yellow River Basin—from 2000 to 2020. The results indicate the following: (1) through desertification control, unused land has been progressively restored to grassland, yet continuous urban expansion has substantially encroached upon surrounding plowland and grassland; (2) the spatial pattern of water conservation supply exhibits a “high in the south and west, low in the north and east” distribution, with the maximum value per pixel increasing from 7.89 × 10⁵ m³ to 8.15 × 10⁵ m³. Overall, water resource carrying capacity has generally declined, with intensified pressure in central cities such as Lanzhou, while some improvement is observed in forested areas of the south; and (3) cold spots in the western Qilian Mountains have expanded toward the Hexi Corridor, reflecting significant spatial changes and indicating ecological degradation. Urbanization has markedly exacerbated regional imbalances in water resource carrying capacity, providing a scientific basis for water–ecological risk management in arid regions. Full article

Efficient water and nitrogen management is essential for maintaining soil fertility and achieving sustainable agricultural production, especially in arid oasis regions where soil degradation and nutrient loss are common challenges. However, the interactions between irrigation regimes, nitrogen application, and soil biological processes in such environments remain insufficiently understood. This study investigated the effects of water and nitrogen management on the sustainability of sandy soil nutrients within the context of the sustainable development goals during silage maize cultivation in the oasis irrigation area of the Hexi Corridor, Northwest China. Four irrigation regimes and five nitrogen management regimes were tested. The results indicate that ammonium nitrogen (NH₄⁺-N) varied significantly during the jointing stage (W4 treatment), ranging from 3.52 to 16.38 mg/kg (p < 0.05). Nitrate nitrogen (NO₃⁻-N) exhibited significant differences during the tasseling stage (W1 treatment), with a range of 6.16–21.58 mg/kg (p < 0.05). Soil total phosphorus (STP) gradually declined from early to late growth stages, ranging from 0.20 to 0.97 g/kg. Regarding enzyme activity, alkaline phosphatase (ALP) increased progressively throughout the growth period, with a range of 0.02–0.14 mg/g/d, while urease (URE) showed a declining trend, ranging from 0.25 to 0.66 mg/g/d. Water management exerted a significant negative effect on soil enzyme activity (p < 0.05), while nitrogen fertilization had a minimal impact on soil microbial communities (p > 0.05). Growth stage and irrigation regime are key regulators of the soil–microbe–enzyme activity system. The crop’s nutrient demand cycles and microbially mediated nutrient transformations exhibited strong dependence on growth stage. Enzyme activity is notably and positively affected by nitrogen inputs and plant developmental stages, while microbial biomass is mainly regulated by soil C, N, and P contents and enzyme activities. These findings provide a scientific basis for implementing water-saving irrigation and high-efficiency fertilization strategies in oasis agricultural systems. Full article

Not enough attention has been paid to the artistic approach of depicting human figures at the center of double-scroll patterns in Chinese Buddhist art. Originating from Greco-Roman culture, this motif entered China from the overland Silk Road around the late 5th century, evolving into two systems. The Hexi Corridor system, centered on Dunhuang, predominantly features lotus-born beings holding vines. The figural types evolved from lotus-born beings to celestial beings, bodhisattvas, and buddhas, with postures ranging from vine-holding to mudra-forming, lotus-tray-lifting, music-playing, and dancing, demonstrating a clear trajectory of development. The Northern Central Plains system, successively centered in Pingcheng, Qingzhou, and Yecheng, developed a relatively complete sequence only in buddha figures. The motif first spread through the Hexi Corridor before influencing the Northern Central Plains. It was adapted from its original Mediterranean context of mythological themes and funerary or temple use to illustrate Buddhist doctrines in China, absorbing elements of Han, Western Regions, and Central Asian cultures. By clarifying the motif’s origin, spread, evolution, and adaptation through systematic analysis of material evidence, this article reveals an intrinsic connection between Greco-Roman culture and Chinese Buddhist art, enriches the history of Sino-foreign cultural exchange, and reflects how Buddhism absorbed diverse cultural elements to achieve Sinicization. Full article

Groundwater is a vital resource in arid regions, where it sustains agriculture, industry, and livelihoods. In northwestern China’s Shule River Basin, located in the Hexi Corridor, increasing water stress has raised concerns about the sustainability of groundwater use. However, the relative contributions of climate variability and human activities to groundwater depletion in this region remain poorly quantified. This study investigates long-term groundwater storage changes in the Shule River Basin from 2003 to 2023 using GRACE satellite data combined with GLDAS land surface models. A water balance approach was applied to isolate natural (climatic) and anthropogenic contributions to groundwater storage anomalies (GWSAs). In addition, land use transitions and socioeconomic indicators were incorporated to assess the impact of human development on subsurface water dynamics. The results show a persistent downward trend in GWSA, with an average annual loss rate of −0.31 cm·yr⁻¹. Spatially, the central and lower reaches of the basin exhibit the most significant depletion, driven by intensive irrigation and urban growth. Contribution analysis indicates that natural factors accounted for 61% of the groundwater loss across the study period, while anthropogenic drivers became increasingly dominant over time, particularly after 2016, accounting for over 40% of total depletion in recent years. Strong correlations were found between groundwater decline and the expansion of cropland, impervious surfaces, and GDP. These findings highlight the intensifying role of human activities in shaping groundwater trends in arid inland basins. This study provides a data-driven framework to support sustainable groundwater management and offers transferable insights for similar water-stressed regions globally. Full article

The coefficient of variation α is a critical parameter in the Brownian Passage Time (BPT) model, used to quantify the variability of large earthquake recurrence intervals. In this paper, a new estimation method is proposed for α based on paleoseismic sequences across multiple faults within a given tectonic region. By integrating Monte Carlo simulations with a Bayesian framework, the method assesses the probability distribution of α without assuming that the sample average recurrence interval equals the true mean μ, thereby avoiding epistemic bias. To validate the method, 1,000,000 simulations were conducted in two study areas of differing spatial scales. In the Western Qilian Mountains-Hexi Corridor, the posterior mean of α is 0.36 (without dating uncertainty) and 0.34 (with uncertainty). Expanding the analysis to 29 faults across western China, the estimated α increases to 0.39 (without dating uncertainty) and 0.36 (with uncertainty), with substantially reduced uncertainty bounds. The results reveal that increasing the number of paleoseismic sequences significantly reduces the uncertainty in estimating α, while considering dating uncertainty has only a minor impact. The methodology provides a robust framework for deriving region-specific recurrence variability parameters and proves particularly valuable for tectonically active regions where individual fault records are sparse but collectively form comprehensive datasets across multiple fault systems. Full article

Atmospheric pollution constitutes one of the key environmental challenges hindering Atmospheric pollution is a key environmental challenge constraining the sustainable development of Gansu Province’s land-based Belt and Road corridor and its regional ecological barrier function. The spatiotemporal heterogeneity of aerosol optical depth (AOD) profoundly impacts regional environmental quality. Based on MODIS AOD, NCEP reanalysis, and emission data, this study employed trend analysis (Mann–Kendall test) and attribution analysis (multiple linear regression combined with LMG and Spearman correlation) to investigate the spatiotemporal evolution of AOD over Gansu Province during 2009–2019 and its meteorological and emission drivers. Key findings include the following: (1) AOD exhibited significant spatial heterogeneity, with high values concentrated in the Hexi Corridor and central regions; monthly variation showed a unimodal pattern (peak value of 0.293 in April); and AOD generally declined slowly province-wide during 2009–2019 (52.8% of the area showed significant decreases). (2) Following the implementation of the Air Pollution Prevention and Control Action Plan in 2013 (2014–2019), AOD trends stabilized or declined in 99.8% of the area, indicating significant improvement. (3) Meteorological influences displayed distinct regional-seasonal specificity—the Hexi Corridor (arid zone) was characterized by strong negative correlations with relative humidity (RH2) and wind speed (WS) year-round, and positive correlations with temperature (T2) in spring but negative in summer in the north; the Hedong region (industrial zone) featured strong positive correlations with planetary boundary layer height (PBLH) in summer (r > 0.6) and with T2 in spring/summer; and the Gannan Plateau (alpine zone) showed positive WS correlations in spring and weak positive RH2 correlations in spring/autumn, highlighting the decisive regulatory role of underlying surface properties. (4) Emission factors (PM_2.5, ${\mathrm{SO}}_4^{2-}$, ${\mathrm{NO}}_3^{-}$, ${\mathrm{NH}}_4^{+}$, OM, and BC) dominated (>50% relative contribution) in 80% of seasonal scenarios, prevailing in most regions (Hexi: 71–95% year-round; Hedong: 68–80% year-round; and Gannan: 69–72% in spring/summer). Key components included BC (contributing > 30% in 11 seasons, e.g., 52.5% in Hedong summer), ${\mathrm{NO}}_3^{-}$ + ${\mathrm{NH}}_4^{+}$ (>57% in Hexi summer/autumn), and OM (20.3% in Gannan summer, 19.0% province-wide spring). Meteorological factors were the primary driver exclusively in Gannan winter (82%, T2-dominated) and province-wide summer (67%, RH2 + WS-dominated). In conclusion, Gansu’s AOD evolution is co-driven by emission factors (dominant province-wide) and meteorological factors (regionally and seasonally specific). Post-2013 environmental policies effectively promoted regional air quality improvement, providing a scientific basis for differentiated aerosol pollution control in arid, industrial, and alpine zones. Full article

The aim of this study was to investigate the method of estimating actual crop evapotranspiration (ET_cact) in a greenhouse using other measured meteorological parameters when solar radiation (R_s) data are missing. The study estimated ET_cact of greenhouse green peppers by combining solar radiation estimation models with the Penman–Monteith (PM) model and evaluated model performance. The results showed that the prediction accuracy of the temperature-based solar radiation model was higher than the model based on sunshine hours in the Hexi Corridor region. The effect of the insulation cover on the incident solar radiation in the greenhouse is modeled by introducing a ramp function. In terms of crop coefficients (K_cb), the initial K_cb value of green peppers in the 2023 growing season was generally consistent with the updated FAO-56 standard values, whereas the initial K_cb values (0.17) were higher than the standard values in the 2023–2024 growing season. During the two growing seasons, the mid-stage K_cb values were 1.01 in the 2023 growing season and 0.82 in the 2023–2024 growing season. The study also found that PM–RT4, PM–RT5, and PM–RT6 models were all able to accurately predict the ET_cact of greenhouse green peppers during the 2023 growing season. The PM–RT4 model performed well in both growing seasons, with R² = 0.8101 in the 2023 growing season and R² = 0.7561 in the 2023–2024 growing season. Our research supports the PM–RT4 model as appropriate to estimate green pepper actual evapotranspiration in Gobi solar greenhouses (GSGs) and may be further used to improve irrigation scheduling for green peppers grown in GSGs. Full article

Glycyrrhiza uralensis (G. uralensis), a leguminous plant, is an important medicinal and economic plant in saline–alkaline soils of arid regions in China. Its main bioactive components include liquiritin, glycyrrhizic acid, and flavonoids, which play significant roles in maintaining human health and preventing and adjuvantly treating related diseases. However, the cultivation of G. uralensis is easily restricted by adverse soil conditions in these regions, characterized by high salinity, high alkalinity, and nutrient deficiency. This study investigated the impacts of four multistrain microbial inoculants (Pa, Pb, Pc, Pd) on the growth performance and bioactive compound accumulation of G. uralensis in moderately saline–sodic soil. The aim was to screen the most beneficial inoculant from these strains, which were isolated from the rhizosphere of plants in moderately saline–alkaline soils of the Hexi Corridor and possess native advantages with excellent adaptability to arid environments. The results showed that inoculant Pc, comprising Pseudomonas silesiensis, Arthrobacter sp. GCG3, and Rhizobium sp. DG1, exhibited superior performance: it induced a 0.86-unit reduction in lateral root number relative to the control, while promoting significant increases in single-plant dry weight (101.70%), single-plant liquiritin (177.93%), single-plant glycyrrhizic acid (106.10%), and single-plant total flavonoids (107.64%). Application of the composite microbial inoculant Pc induced no significant changes in the pH and soluble salt content of G. uralensis rhizospheric soils. However, it promoted root utilization of soil organic matter and nitrate, while significantly increasing the contents of available potassium and available phosphorus in the rhizosphere. High-throughput sequencing revealed that Pc reorganized the rhizospheric microbial communities of G. uralensis, inducing pronounced shifts in the relative abundances of rhizospheric bacteria and fungi, leading to significant enrichment of target bacterial genera (Arthrobacter, Pseudomonas, Rhizobium), concomitant suppression of pathogenic fungi, and proliferation of beneficial fungi (Mortierella, Cladosporium). Correlation analyses showed that these microbial shifts were linked to improved plant nutrition and secondary metabolite biosynthesis. This study highlights Pc as a sustainable strategy to enhance G. uralensis yield and medicinal quality in saline–alkali ecosystems by mediating microbe–plant–nutrient interactions. Full article

Elucidating the trade-offs and synergies among ecosystem services is crucial for effective ecosystem management and the promotion of sustainable development in specific regions. The Hexi Corridor, a vital agricultural hub in Northwest China, is instrumental in both ecological conservation and socioeconomic advancement throughout the area. Utilizing an integrated “water–soil–carbon–grain” framework, this study conducted a quantitative assessment of four essential ecosystem services within the Hexi Corridor from 2000 to 2020: water yield, soil conservation, vegetation carbon sequestration, and grain production. Our research thoroughly explores the equilibrium and synergistic interactions between grain production and other ecosystem services, while also exploring potential strategies to boost grain yields through the precise management of these services. The insights garnered are invaluable for strategic regional development and will contribute to the revitalization efforts in Northwest China. Key findings include the following: (1) between 2000 and 2020, grain production exhibited a steady increase, alongside rising trends in water yields, soil conservation, and carbon sequestration, all of which demonstrated significant synergies with agricultural productivity; (2) in areas identified as grain production hotspots, there were stronger positive correlations between grain output and carbon sequestration services, soil conservation, and water yields than the regional averages, suggesting more pronounced mutual benefits; (3) the implementation of strategic initiatives such as controlling soil erosion, expanding afforestation efforts, and enhancing water-saving irrigation infrastructure could simultaneously boost ecological services and agricultural productivity. These results significantly enhance our comprehension of the interplay between ecosystem services in the Hexi Corridor and present practical approaches for the optimization of regional agricultural systems. Full article