Search Results (403)

The Z-scheme Ag₂MoO₄/BiOCl heterojunction with oxygen vacancies was successfully fabricated at a low temperature via a simple in situ precipitation method. The morphological, structural, and optical characteristics of the Ag₂MoO₄/BiOCl heterojunction were systematically examined. The optimized synthesized Ag₂MoO₄/BiOCl heterojunction achieved a removal rate of 80.44% for ciprofloxacin within 180 min of simulated solar irradiation, which was 3.27 and 1.90 times higher than that of pure Ag₂MoO₄ and BiOCl, respectively. The fabricated Z-scheme heterojunction and oxygen vacancies optimize the electron transfer route, enhancing the separation efficiency of photogenerated electrons and holes. Moreover, the active species trapping experiments and ESR analyses demonstrated that holes were the primary reactive species involved in the photocatalytic process. It was hypothesized that the Ag₂MoO₄/BiOCl heterojunction adhered to a Z-scheme mechanism for charge transfer. The straightforward approach opened up novel avenues for the synthesis of efficient BiOCl-based photocatalysts aimed at environmental remediation. Full article

Net primary productivity (NPP) is a key indicator of the carbon sequestration capacity of terrestrial ecosystems, and its dynamics are jointly influenced by climate change and human activities. However, quantitatively disentangling their respective contributions and clarifying their non-linear interactions remains challenging. In this study, remote sensing, meteorological, and anthropogenic data were integrated to investigate the spatiotemporal dynamics of vegetation NPP in the Yellow River Basin (YRB) from 2000 to 2024. Six scenarios were constructed to quantify the relative contributions of climate change and human activities. Furthermore, an XGBoost-SHAP framework was employed to elucidate the underlying non-linear driving mechanisms. The results indicate that vegetation NPP exhibited a significant increasing trend over the study period, with a rapid recovery phase after 2012 and a peak in 2024 (351.75 gC·m⁻²·a⁻¹), representing a 71.43% increase compared with the baseline period. Spatially, the upper reaches were primarily climate-driven (58.74%), the middle reaches showed a strong synergistic effect between climate and human factors (97.41%), while the lower reaches were dominated by human activities (73.02%). The XGBoost-SHAP analysis identifies land surface temperature (LST) as the primary moderator of carbon sequestration across river basins (mean SHAP > 12.0). The driving mechanisms exhibit a clear longitudinal shift, transitioning from a heat-dominated regime in the upper reaches to a complex interplay of precipitation and intense urbanization in the middle and lower reaches. These non-linear interactions reveal critical feedback loops between natural hydrological constraints and urban expansion pressures. These findings clarify the drivers of regional carbon sequestration, providing a scientific basis for targeted ecological management and carbon neutrality strategies in the YRB. Full article

Soil heavy metal pollution poses a threat to agricultural sustainability, food safety, and human health. The ecologically fragile Yellow River Basin is a critical hub for agriculture, energy, and mining; however, soil heavy metal studies remain fragmented, and basin-wide syntheses are limited almost entirely to agricultural soils. This study presents a basin-wide analysis of As, Cd, Cr, Cu, Ni, Pb, and Zn in topsoil, based on 2498 sampling locations compiled from 347 publications, using an integrated framework of receptor modeling, multivariate spatial statistics, self-organizing maps, and probabilistic human health and ecological risk assessment. Four pollution sources, namely agricultural–industrial, emissions, mining–smelting, and geogenic/lithogenic, were resolved. Agriculture–industry and emissions posed considerable ecological risks (mean PER = 367.9 and 353.4), with Cd and Pb accounting for 95.7% of the risk. The non-carcinogenic hazard was negligible for adults, but 8.6% of sites exceeded the safe threshold for children, and the carcinogenic risk surpassed 10⁻⁶ for all groups, with 2.6–9.6% of sites exceeding 10⁻⁴. Spatially, the strongest multimetal contamination corridors are the Baiyin–Lanzhou corridor (upper–middle reaches) for Cu-Pb-Zn (mining–smelting) and the Xi’an–Weinan belt (middle reaches) for Cd-Pb (agricultural–industrial and emissions). Multivariate clustering was more extensive (56.1% of sites) than single-metal clustering (13.1–26.2%), confirming coherent source-linked zones. Ecological risks were driven by Cd and Pb, whereas human health risks were driven by As, Cr, and Ni. This divergence and the strong spatial organization of the risk clusters highlight the need for source-specific, spatially targeted mitigation, which requires monitoring across all land use types. The compiled dataset, although extensive, is constrained by heterogeneity in sampling periods and analytical methods and by sparse coverage in some grassland, desert, and plateau regions. Full article

Amid tightening ecological constraints, accelerating urbanization transition, and increasingly complex spatial governance, the coordinated evolution of Urban Green Space (UGS) and New-Type Urbanization (NTU) has become central to green transition and high-quality development in major river basins. Drawing on city-level panel data for the Yangtze River Economic Belt (YREB) and the Yellow River Basin (YRB) from 2006 to 2022, this study integrates a Coupling Coordination Degree (CCD) model, spatial statistical analysis, and interpretable machine learning to investigate UGS-NTU coordination, with emphasis on spatiotemporal evolution, spatial differentiation, and nonlinear contribution pathways. The findings indicate that: (1) UGS and NTU levels rise in both basins, but their spatial trajectories differ substantially. The YREB exhibits river-oriented expansion and gradient diffusion, whereas the YRB features nodal agglomeration and discontinuous expansion. (2) The CCD improves overall in both basins, with downstream areas leading, the middle reaches following, and the upper reaches lagging behind; UGS lag is widespread in the middle and upper reaches. (3) The YRB shows stronger spatial agglomeration, more pronounced regional differentiation, and more persistent low-value clustering, while the YREB is characterized by stable high-value clustering in the Yangtze River Delta. (4) The YREB is mainly associated with green space system optimization, whereas the YRB is more closely associated with improvements in the foundational capacities of NTU. Both associations exhibit clear nonlinear characteristics. This study provides empirical support for differentiated green transition and high-quality development strategies in major river basins. Full article

Pisha sandstone (PS) is a weakly cemented soft rock widely distributed in the middle reaches of the Yellow River, China. PS disintegrates rapidly upon contact with water and has poor erosion resistance, making it a major source of coarse sediment in the Yellow River. However, PS is rich in aluminosilicate minerals and clay fractions, offering great potential as a sustainable precursor for geopolymer cementitious materials and as an amendment for degraded soils. The sustainable resource utilization of PS provides a new pathway for coordinated ecological and economic development in the PS areas. This paper first reviews the mineralogical and chemical characteristics of PS, clarifying that low diagenetic degree and high montmorillonite content cause poor erosion resistance, and that compound erosion from freeze–thaw, water, wind, and gravity erosion creates a superimposed amplification effect, which is the primary driver of severe soil erosion. Subsequently, three major control measures for soil erosion in the PS areas are summarized, namely biological measures using sea-buckthorn (Hippophae rhamnoides), chemical solidification, and microbially induced calcium carbonate precipitation (MICP), with analyses of their mechanisms, efficiency, and limitations. Furthermore, the research progress on the sustainable resource utilization of PS in the preparation of geopolymer cementitious materials and the amelioration of degraded soils is elaborated. Finally, future research directions are discussed to support the control of soil erosion and the green, sustainable resource utilization of PS. Full article

Urban–rural integration (URI) represents a pivotal pathway to realizing sustainable development within urban–rural spatial systems. It is of paramount importance in addressing the challenge of reconciling ecological conservation with high-quality development in the Yellow River Basin. Leveraging panel data from 78 cities in the Yellow River Basin spanning the years 2006–2023, this research constructs an evaluation index system that encompasses five dimensions: population, economy, society, ecology, and space. Through the comprehensive application of kernel density estimation, exploratory spatiotemporal data analysis, and panel quantile regression models, a systematic analysis of the spatiotemporal evolution patterns and transition mechanisms of URI is conducted. The results disclose that URI in the Yellow River Basin demonstrates a trend of “overall enhancement with regional disparities”. From 2006 to 2023, the URI of the basin witnessed an average annual growth rate of 2.86%. Spatially, it presented distinct features: high-level agglomeration in the lower reaches, accelerating-growth path dependency accompanied by internal divergence in the middle reaches, and balanced yet low-level development in the upper reaches. The local spatial evolution of URI follows a pattern characterized as “predominant stability and limited transitions”. In detail, high-level regions sustain their advantages, low-level regions encounter obstacles in achieving breakthroughs, and the spillover effects between adjacent regions remain relatively restricted. The driving mechanisms exhibit significant “phase-spatial” dual heterogeneity, with four distinct patterns identified. In light of these findings, policy recommendations are put forward, including the establishment of a multi-scale, coordinated spatial governance system. Full article

Loess slopes are prone to rapid infiltration, surface erosion, and shallow instability under intense rainfall, highlighting the need for eco-friendly shallow protection methods with enhanced anti-seepage and erosion resistance. To improve the applicability of microbially induced calcite precipitation (MICP) in loess slope protection, this study proposes a combined MICP–sesbania gum (SG) modification method. Permeability tests, surface hardness tests, and indoor artificial rainfall model tests were conducted to systematically evaluate its effects on seepage control and the erosion resistance of loess slopes. The results show that calcium chloride provides a stronger permeability-reducing effect than calcium acetate. Compared with the MICP-only treatment, the combined MICP-SG treatment significantly reduces the permeability coefficient and increases surface hardness. Based on the overall modification performance, a cementation solution concentration of 1.0 mol/L and a curing time of 7 d were selected as suitable treatment parameters. Rainfall model tests further demonstrate that the combined treatment delays erosion failure, reduces infiltration rate and soil loss, and suppresses wetting front migration and internal water content response. These findings indicate that MICP combined with SG can effectively improve the anti-seepage, erosion resistance and surface stability of shallow loess slopes, providing experimental support for eco-friendly shallow slope protection in loess regions. Full article

Taking the Yellow River Basin (YRB) as an example, this study explores the non-stationary drought evolution features in large river basins under climate change. This study utilized precipitation and multiple climate factor data to establish the non-stationary standardized precipitation index (NSPI) through the GAMLSS model. Combined with the run theory, Copula function and a cascaded RF-LSTM machine learning model, the drought characteristics and retrospective predictive patterns were systematically assessed. The results show that: (1) The Arctic Oscillation, the Pacific Decadal Oscillation, the Southern Oscillation and the North Pacific Index are the primary climate drivers of non-stationary precipitation variation in the YRB, with the former three being selected most frequently and NPI additionally influencing April–June and September, and their effects are both different and lagging. Compared with the traditional SPI, the NSPI assigned higher drought grades and greater severity to typical drought years (e.g., the 1974 event was rated D3 with a severity of 17.935 by NSPI versus D2 with 11.733 by SPI), and thus better captured non-stationary drought evolution. (2) The duration of droughts exhibited a decreasing trend that was not statistically significant (p > 0.05), whereas drought intensity and severity decreased significantly (p < 0.05); the peak severity showed a significant upward trend (p = 0.0078). Spatially, the northwest of the Loess Plateau was a compound core area with high severity, high frequency and long duration of droughts, while the upper reaches were mainly characterized by low severity, short duration and sudden droughts. (3) The drought risk in the YRB shows a higher frequency in the lower reaches and a lower frequency in the upper reaches. The middle and lower reaches were high-risk areas, with shorter AND-type joint exceedance return periods for moderate drought (2.46–5.83 years) and severe drought (3.77–9.15 years). The upper reaches were low-risk areas, with longer return periods reaching up to 5.83 years for moderate drought and 9.15 years for severe drought. The study shows that the NSPI, considering the driving of multiple climate factors, can more effectively identify and assess non-stationary drought risks, providing a scientific basis for drought prevention and control in river basins. Full article

Polycyclic aromatic hydrocarbons (PAHs) in farmland soils pose potential ecological and human health risks, yet their contamination characteristics and source-related risks in farmland soils across different river basins in China remain insufficiently understood. This present study analyzed 84 farmland soil samples from northeast (primarily the middle and lower reaches of the Songhua River and Liao River basin), central (primarily the middle reaches of the Yellow River basin and Dongting Lake system), northwest (primarily the middle and upper reaches of the Yellow River and Yarlung Zangbo River basin), and southern (primarily the upper reaches of the Pearl River and Yangtze River basin) China in order to assess the contamination characteristics, sources, ecological risks, and human health risks associated with 16 US EPA priority PAHs in the samples. The findings suggest that the 16 aggregate PAHs’ concentrations in Chinese farmland soils varied from 63.9 to 9637.7 μg/kg, with an average of 1919.3 μg/kg. A gradual decline was observed from north to south, with dibenz[a,h]anthracene (DahA) accounting for the highest proportion at 14.3%. Correlation analysis, principal component analysis, and positive matrix factorization jointly indicated that fossil fuel combustion, high-temperature combustion, and traffic-related emissions were the main PAH inputs to farmland soils. The results of the ecological risk assessment indicated that the northeastern region exhibited the highest PAH ecological risk, with 41.2% of sample plots demonstrating severe PAH contamination. Conversely, the southern region exhibited the lowest PAH ecological risk, with 73.9% of the sample plots demonstrating no ecological risk. The human health risk assessment found that non-carcinogenic risks for both children and adults were within safe limits, while carcinogenic risks for both groups were relatively high. DahA was identified as the primary carcinogen, accounting for 45.9% and 70.3% of the total carcinogenic risk for children and adults, respectively. Oral ingestion was the primary route of exposure. This study provides an integrated basin-scale assessment of PAH contamination and source-related risks in Chinese farmland soils, supporting targeted management of PAH inputs in agricultural environments. Full article

The White-naped Crane (Antigone vipio), a first-class national protected bird species in China, exhibits a declining global population. To investigate the spatiotemporal patterns and drivers of wintering habitat suitability, data from 71 valid distribution sites were collected from 2015 to 2025 during the wintering period. Using the MaxEnt model, current and future (2050 and 2070) potential suitable habitat distributions were simulated under three climate scenarios: SSP126 (low emissions), SSP245 (medium emissions), and SSP585 (high emissions). The modeling yielded an average AUC value of 0.984, indicating high predictive accuracy. Key environmental variables influencing the wintering distribution of the White-naped Cranes include elevation, distance to major water, precipitation of the driest month, slope, temperature seasonality, and mean temperature of the wettest quarter. The current high-suitable area for the White-naped Cranes spans 5.64 × 10⁴ km² and is primarily distributed in the middle and lower reaches of the Yangtze River and in coastal wetlands along the North China. Among these, Hunan, Hubei, Jiangxi, and Anhui provinces contain relatively concentrated high-suitable areas for the species. Primarily influenced by elevation, distance to major water, precipitation of the driest month, and land-use classification, the suitable wintering habitat of the White-naped Cranes is projected to undergo significant contraction, shifting predominantly to the middle reaches of the Yangtze River. The most severe contraction is projected under the SSP585 scenario by 2070, with a reduction of 4.11 × 10⁵ km². Contraction areas are primarily concentrated along the Bohai and Yellow Sea coasts and in the middle and lower reaches of the Yangtze River, while minimal expansion occurs in Hubei, Anhui, and Zhejiang. The overall southwestward shift in the species’ distribution centroid may be associated with changes in elevation and distance to major water. Finally, habitat conservation strategies for the White-naped Cranes are proposed, providing a scientific basis for population protection and habitat management under future climate change. Full article

Soil salinization threatens agricultural production, and increasing extreme rainfall may alter natural leaching processes in coastal saline–alkaline soils. However, the relationships among salt ion migration, alkalinity changes, nutrients, and bacterial communities under natural rainfall leaching remain unclear. Therefore, a phased natural rainfall leaching experiment was conducted from June to September 2025 using moderate to severe NaCl-type saline–alkaline soil from Dongying in the Yellow River Delta. The results showed that natural rainfall leaching significantly reduced soluble salt ions, especially Na⁺, Cl⁻, and SO₄²⁻, and rapidly alleviated early salt stress. However, soil pH did not decline continuously with salt reduction, but fluctuated under the buffering effect of the carbonate system, indicating that desalination was not necessarily accompanied by alkalinity alleviation. Available nutrients showed stage-dependent changes, with HN and AK increasing around the middle leaching stage. Bacterial community composition and co-occurrence networks also changed during leaching, and these changes were more closely associated with salt ions and HCO₃⁻/pH than with available nutrients. These results suggest that post-rain management of saline–alkaline soils should not rely only on total salinity, but should also consider major salt ions, pH/HCO₃⁻, and nutrient availability. Full article

Rhinogobio nasutus, an endangered fish species endemic to the upper and middle reaches of the Yellow River in China, lacks essential genomic information on gonadal development, hindering research into its reproductive biology. To address this, mRNA-seq and miRNA-seq datasets derived from adult testis (n = 3) and ovary (n = 3) were integrated to characterize sex-biased expression profiles and potential regulatory mechanisms. A total of 34,813 genes and 68,623 transcripts were detected, and 16,105 differentially expressed genes (DEGs) were identified between testis and ovary, including 9365 testis-biased and 6740 ovary-biased genes. Small-RNA profiling identified 51 differentially expressed miRNAs (DEMs: 31 testis-biased; 20 ovary-biased). The sex-biased mRNA profiles highlighted conserved candidate genes associated with germ-cell maintenance, somatic regulation, ovarian differentiation, and oocyte maturation, including vasa, piwi, dmrt1, amh, cyp19a1a, zar1, zar1l, and rbpms2. Integrated miRNA–mRNA analysis further predicted potential interactions involving key sex-related genes, suggesting that DEMs may contribute to post-transcriptional regulation during gonadal differentiation. Functional enrichment (GO and KEGG analyses) highlighted pathways associated with gonadal differentiation, germline maintenance, and signal transduction pathways. qRT-PCR validation of nine mRNAs and nine miRNAs showed expression patterns consistent with the sequencing results. Collectively, these results provide an integrated mRNA and miRNA resource for R. nasutus gonads and identify candidate genes and miRNAs for future studies on sex-biased gonadal development, reproductive regulation, and artificial propagation. Full article

Enhancing green development efficiency (GDE) is crucial for promoting ecological protection and high-quality growth in the Yellow River Basin (YRB). Using panel data from 48 prefecture-level cities in the YRB from 2010 to 2022, this study applies a Super-SBM model that accounts for undesirable outputs to measure GDE. Then, a modified gravity model and social network analysis (SNA) are used to identify the evolution of its spatial correlation. Additionally, a spatial Durbin model (SDM) is employed to examine the driving mechanisms from the dual perspectives of the innovation rebound effect and external micro-ESG (Environmental, Social, and Governance) reverse-forcing pressure. The results reveal the following: First, the spatial pattern of GDE in the YRB has changed significantly, showing an overall spatial imbalance, with efficiency improvements in the middle reaches and declines in the lower reaches. Notably, resource-based cities have improved GDE due to environmental regulations. Second, the spatial correlation network has evolved from a point-axis layout to a more complex network structure. However, spatial links among cities are mainly driven by geographic proximity, while collaborative ties between cities with similar economic features remain weak. Third, technological innovation has a significant negative effect on local GDE, likely due to the energy rebound effect. Meanwhile, the cross-regional transmission of the external supply chain ESG reverse-forcing mechanism remains weak, constrained by the carbon lock-in effect in the middle and upper reaches. These findings suggest that internal technological structures and external market constraints both influence GDE in the YRB. This research offers an empirical foundation for developing targeted, cross-regional collaborative governance policies. Full article

A scientific understanding of the relationship between artificial intelligence (AI) and agricultural carbon sinks (ACS) is essential for promoting the low-carbon transformation of agriculture in the Yellow River Basin, accelerating the achievement of the “dual carbon” goals, and enhancing the high-quality development of the regional economy. Using panel data from 97 cities in the Yellow River Basin in China from 2001 to 2023, this study measures the levels of ACS and agricultural net carbon sinks (ANCS), and further examines the mechanisms, regional heterogeneity, and moderating effects associated with the impact of AI on both indicators. The results indicate that: (1) AI significantly improves ACS and ANCS in cities within the Yellow River Basin. Specifically, for every 1% increase in AI development, ACS and ANCS increase by approximately 0.0111 million tons and 0.0138 million tons, respectively. This effect is more pronounced in the upper and lower reaches of the basin, while remaining insignificant in the middle reaches; (2) AI promotes improvement in ACS and ANCS by increasing the level of agricultural mechanization and the intensity of chemical fertilizer application; (3) Grain yield per unit area and agricultural planting structure positively moderate the relationship between AI and both ACS and ANCS. Overall, the findings suggest that AI plays a significant positive role in enhancing ACS and ANCS. Therefore, greater emphasis should be placed on the cultivation, diffusion, and application of AI technologies to achieve the sustained improvement of ACS and ANCS capacity in the Yellow River Basin. Full article

Forest tourism represents an important pathway for promoting green consumption, with forest parks serving as the primary platform for its development. The coordinated development of forest parks is therefore essential for achieving integrated economic, social, and ecological benefits. Investigating the coordination and coupling between ecological resilience and tourism economy in forest parks of the Yellow River Basin along with driving factors carried substantial practical significance for balancing regional economic development with ecological conservation. The present research developed an indicator system that was comprehensive and dynamic for assessing ecological resilience across forest parks in nine provinces of the Yellow River Basin during 2013–2023. To investigate patterns of spatiotemporal evolution and uncover underlying driving mechanisms, exploratory spatial data analysis was combined with a spatiotemporal geographically weighted regression model. The main findings are as follows: (1) The integrated levels of ecological resilience and tourism economy across the Yellow River Basin showed significant spatiotemporal heterogeneity. From north to south, a high–low–high spatial pattern was exhibited by ecological resilience, while a core concentration and gradient diffusion pattern was demonstrated by the tourism economy. (2) The coupling coordination level between forest park ecosystems and the tourism economy increased, with a growing number of provinces transitioning toward coordinated and near–dysregulated states, although pronounced regional disparities persisted. (3) Kernel density analysis indicated an overall improvement in coordination, accompanied by strong regional differentiation. The upper reaches displayed a unipolar leading pattern, while the middle and lower reaches showed multipolar differentiation and a pronounced “Matthew effect”. (4) Technological innovation emerged as the core driving factor, though its influence varied considerably across regions. Overall, these findings provide theoretical support and empirical evidence for policy formulation aimed at achieving a balance between ecological conservation and economic development in forest park systems. Full article