Qilian Mountain National Park, serving as a vital ecological barrier in northwest China, urgently requires achieving a balance between conservation and management. This study aims to elucidate the spatiotemporal dynamics of landscape patterns, landscape ecological risks (LERs), and ecosystem services (ESs), and reveal their response relationships. Based on risk-service response optimization, ecological zoning is established, and adaptive strategies are proposed. The research integrates multi-source data within a "pattern-process-service-sustainability" framework, employing methods including landscape indices, the multiscale geographically weighted regression (MGWR) model, the LER-ES coupling model, and the Geodetector model. Key findings are as follows: (a) Landscape fragmentation decreased by 12.3% from 2000 to 2020, with an average annual reduction of 2.1% in LER and weakened spatial clustering intensity. An east-west gradient in LER persisted. (b) The comprehensive capacity of ESs improved, exhibiting a southeast-northwest gradient distribution. (c) The MGWR model confirmed that LER negatively impacts ecological services, with spatial nonstationarity present. (d) Ecological zones were classified into protected areas, stable areas, sensitive areas, and vulnerable areas, with obvious differences in driving factors-environmental vulnerability was primarily dominated by natural factors, while relatively stable areas were more significantly influenced by human activities. This represents the first zoning based on the risk-service relationship, breaking through traditional limitations.

Urban green belts (GBs) have multiple functions of providing ecosystem carbon storage services, improving urban microclimate, and inhibiting urban sprawl. However, there is a paucity of studies to assess the dynamics of the ecosystem carbon storage function of the GB around the city and forecast its future potential. Our study analyzed the dynamic changes of carbon stock in Beijing's GB during 2000 to 2020 and predicted the GB's carbon storage potential in 2035 by coupling the InVEST and FLUS models. Results showed that Beijing's GB carbon storage decreased from 14.45 to 10.59 Mt from 2000 to 2020. The carbon density of the GB in Beijing from 2000 to 2010 was greater than that of the non-GB areas, indicating that the GB had a substantial carbon storage function. The carbon stock in Beijing's GB showed the spatial characteristics that the high carbon stock zones were located in the western part of the GB under 3 scenarios in 2035. The overall carbon stock in 2035 under the economic development scenario was 35.60 Mt, with the largest reduction from 2020, 1.78 Mt. The spatial layout, morphology, and structure of urban GB had a notable effect on carbon storage function, and the protection and spatial regulation of urban GB systems should be strengthened in the future in terms of urban-rural development and planning, the morphology and scale of GB, and institution and public support.

Rapid urban development has led to the anthropogenic disruption of natural river connectivity, posing unprecedented threats to aquatic biological communities. Understanding how river connectivity influences the structure of these communities is crucial, particularly in urban mountainous regions where this topic remains underexplored. Here, we assessed river connectivity in the Mother River of Beijing, one of the world's largest megacities, and analyzed its effects on the biodiversity, dominant species, and biomass of benthic fauna, zooplankton, phytoplankton, and fungi. Our results showed that the river connectivity index (RCI) ranged from 0.0003 to 0.3978, with higher connectivity observed in the middle reaches of the river. RCI values were distinctly categorized into 2 types: high connectivity and low connectivity. Organisms at different trophic levels exhibited varying responses to river connectivity, with the composition of dominant benthic species differing by 62.5% between connectivity conditions, a higher variation than that observed in other taxa. Notably, diatom richness displayed significant spatial heterogeneity and was strongly negatively correlated with RCI. Our findings demonstrate that river connectivity exerts taxon-specific effects across multiple trophic levels, underscoring the need to consider both faunal diversity gains and potential diatom losses when designing urban river restoration and conservation strategies.

The Chinese Loess Plateau has approached a critical threshold in vegetation restoration, requiring optimized land-use strategies for sustainable ecosystem management. This study examines soil organic carbon (SOC) content and associated soil properties across 0 to 500 cm soil profiles under 4 land-use types (grassland, shrubland, forestland, and cropland) in the Gutun Basin. SOC dynamics were assessed using acid-soluble carbon (F1) and carbon components extracted at combustion temperatures of 25 to 400 °C (F2), 400 to 600 °C (F3), and 600 to 900 °C (F4). Based on ¹⁴C ages, F1 to F3 were classified as labile components, whereas F4 was considered nonlabile. Although cropland exhibited the highest SOC stock (0.88 ± 0.38 kg m⁻²), it also had the highest proportion of nonlabile carbon (75%). The similar ¹⁴C ages of deep-soil carbon components in shrubland and forestland, along with higher carbon content in deep layers, suggested that carbon sequestration could occur at depths of at least 300 to 500 cm. However, soil water content (SWC) in shrubland and forestland was significantly lower (93.71 ± 44.94 and 71.15 ± 17.62 g kg⁻¹, respectively), and forestland exhibited lower SOC content (1.77 ± 0.56 g kg⁻¹). Among all land-use types, grassland had a significantly higher SOC content (3.96 ± 2.56 g kg⁻¹), a greater proportion of labile carbon (77%), and a higher SWC (132.06 ± 21.71 g kg⁻¹), suggesting that it was the most suitable land-use type in this context.

The natural environment provides the geographical foundation for human survival and development; however, its suitability for human settlement in high-altitude regions remains insufficiently addressed. This study focuses on the Tibetan Plateau and proposes a Natural Environment Suitability Index of the Plateau (NESP), designed specifically for high-altitude areas. Using the natural location quotient, we assessed the influence of 9 key environmental factors on settlement suitability. To determine indicator weights objectively and comprehensively, we applied 3 methods: the random forest method, the consulting graded method, and the correlation coefficient method. The results indicate a clear spatial gradient: environmental suitability decreases from east to west as altitude increases. Only about 31% of the plateau is categorized as suitable or very suitable, primarily in low-altitude river valleys, while over 69% is classified as unsuitable or very unsuitable, concentrated in central and western regions. Suitable or very suitable areas are deemed appropriate for regulated human activities under strict environmental protection, while unsuitable or very unsuitable regions should be prioritized for ecological conservation. Based on the NESP, we delineated 11 distinct natural suitability zones across the plateau. This study offers a high-altitude-specific framework for assessing the quality of the natural environment for human settlement, providing a scientific foundation for regional planning, environmental management, and the promotion of Sustainable Development Goals in fragile plateau ecosystems.

The interplay of extreme precipitation and high temperature markedly diminishes the carbon sink capacity of China's terrestrial ecosystems. Although the spatiotemporal evolution characteristics of these extreme events have been initially identified, their impacts on gross primary production (GPP) remain inadequately quantified. With the multisource data (1981 to 2100) of 4 shared socioeconomic pathways (SSPs), the Mann-Kendall test, empirical orthogonal function, and center of gravity shift models were used to identify the spatiotemporal evolution of GPP, and the structural equation model was used to elucidate the pathways and contributions of extreme events to GPP changes. GPP increased nationwide (0.02 to 0.07 kg C m⁻² a⁻¹ decade⁻¹, P < 0.05), with growth varying by scenario and there is regional heterogeneity; the first principal mode of GPP was positive in most areas (59.55% to 100%), with the same increasing and decreasing characteristics; the spatial centroid of GPP exhibited a shift from the east and south toward the west and north, accompanied by marked ecosystem greening; extremely high temperature exerted the most -substantial negative influence on GPP under SSP5-8.5 (standardized path coefficients: −0.580), whereas extreme precipitation duration in SSPs 1-2.6 and 3-7.0, and intensity in SSP2-4.5. The total effect of extreme events on GPP change shifts from a positive to a negative effect (0.966 → −0.655, −167.81%) with increasing carbon emissions. Negative effects are concentrated in Northeast China, East China shows alternating positive and negative effects, and the other regions shift from positive to negative effects. This study emphasizes the importance of differentiated climate change adaptation capacity building.

Highly urbanized cities have undergone substantial land use changes driven by intensive human activities, leading to increasingly prominent ecological security challenges. This study employed landscape pattern indices to evaluate the landscape ecological risk (LER) across 275 prefecture-level cities in China from 2011 to 2019. We hypothesized that the mechanisms influencing LER vary according to the level of urbanization. An integrated panel threshold regression model was applied to examine this hierarchical influence and identify potential thresholds in the urbanization rate (UR). In addition, the spatial spillover effects of LER were investigated using a spatial panel econometric model. Our findings revealed an initial increase in LER from 2011 to 2013, followed by a notable stabilization between 2015 and 2019, with evident spatial heterogeneity. Using UR as the threshold variable, the normalized difference vegetation index, population density, and per-capita gross domestic product (PGDP) were found to exert nonlinear impacts on LER, which were consistent across multiple model specifications. A critical threshold was identified at a UR of 62.1%, beyond which the influence of PGDP on LER altered substantially. Spatial spillover effects of LER were also stronger in cities below this UR threshold, implying that highly urbanized cities may possess self-regulatory ecosystem mechanisms that mitigate LER. Based on the results, the development of secondary and tertiary industries, alongside the construction of infrastructure, could mitigate LER for low-urbanization cities. In highly urbanized cities, blue-green space planning should be strategically aligned with industrial transformation and upgrading, thereby bolstering urban ecological protection and contributing to long-term environmental sustainability.

To address the climate crisis, policy interventions are driving a structural transition in the power sector, which potentially alters the evolutionary trajectories of related carbon emissions and water consumption. Based on China's 2060 Carbon Neutrality Initiative, an integrated system dynamics model was developed to analyze the power generation transition and its interlinked impacts on decarbonization and water sustainability, considering policy-driven electricity generation and the energy-water-carbon nexus. The model was applied to China over the period 2000 to 2060. Results indicate that by 2060, China's electricity demand is projected to surge to 13 trillion kWh, with thermal power generation peaking around 2030 before declining to a lower level. This process would achieve cumulative reductions of 65 gigatons of carbon emissions and water savings of 60 km³. Wind and solar power are expected to account for 70% of the total amount, becoming the primary substitutes for the phased-out thermal power capacity. Scenario simulations reveal that this can enhance synergistic benefits for carbon mitigation and water conservation. However, the deployment of carbon capture and storage technologies may introduce a trade-off between carbon reduction and water consumption. To mitigate this issue, integrating water-saving devices as air-cooled units into power production chains could offset additional water consumption. Clearly, the phaseout of thermal power represents a pivotal measure for optimizing the power industry. The substitution by high-quality energy products will benefit carbon emission reduction and sustainable water utilization, yet when deploying new technologies, the integration of functional and efficient technologies should be taken to prevent unintended trade-offs.

Wind erosion prevention service (WEPS) is critical for mitigating soil erosion and desertification in China's arid-semiarid zones. However, most existing studies have overlooked the spatial flow of WEPS, particularly the interannual variability and seasonal dynamics of sand transport pathways. This study focused on the loess hilly-gully region (LHGR), a climate-sensitive zone with intensified aeolian activity. We quantified the spatiotemporal dynamics of WEPS from 2000 to 2020 and simulated sand transport trajectories to assess cross-regional effects and socioeconomic dynamics. The results showed a marked increase in WEPS, indicating improved capacity of wind erosion prevention, with persistently high-value zones concentrated in northwestern arid regions such as the Mu Us Sandy Land. Wind trajectory identified 2,783 transport paths, dominated by spring winds (57.96%), which carried dust eastward toward densely populated areas and transboundary regions like Japan. Beneficiary areas exhibited a concentric spatial pattern, covering 599.96 × 10⁴ km² (62.5% of China). The growing population, gross domestic product, and ecosystem service value highlighted its dual role in safeguarding human health and supporting sustainable development. Fraction vegetation coverage (FVC) emerged as the dominant factor for actual wind erosion by increasing surface roughness, with China's ecological restoration policies amplifying this function. Precipitation (PRE) predominantly regulated potential wind erosion, while synergistic interactions between FVC, PRE, and other drivers underscored the necessity for multi-factor governance. Our framework integrating physical flow and beneficiary mapping provides practical insights for optimizing payment for ecosystem service to enhance cross-regional ecological benefits.

The water-energy-food (WEF) nexus is essential for balancing resource use, yet most assessments overlook mismatches between administrative boundaries and ecological processes. This study developed a dual-scale framework for 105 counties and 89 sub-watersheds in Anhui Province, China, to quantify WEF supply-demand relationships and guide spatial governance. The InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model, supply-demand index (SDI), 4-quadrant model, and entropy-weighted TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) model were applied to assess water yield, carbon storage, and food production supply-demand relationships. Additionally, a 4-step methodology was developed to delineate management zones. The results showed the following: (a) From 2000 to 2020, water supply increased by about 92% while demand rose by 97%. Food supply grew by 63%, whereas demand declined by 37%. Energy supply remained nearly stable, but demand surged by more than 340%. Both county and sub-watershed scales captured these overall patterns, while the sub-watershed perspective revealed sharper local fluctuations. Cross-service interactions were observed with trade-offs between W-F and E-F and synergies between W-E supply, reflecting the complex ecological coupling within the WEF nexus. (b) Supply-demand matching indicated that water and energy were deficit-dominated and food was surplus-oriented. The food SDI improved more markedly at the sub-watershed scale (0.04 to 0.50) than at the county scale (0.01 to 0.37), showing stronger local recovery and more evident clusters of mismatches. (c) The study area was divided into 3 resource partitioning zones, 4 matching typologies, and 4 priority strategies, and merged into 9 integrated governance zones. This research can give complementary insights from dual scales enabling targeted strategies for integrated WEF management in ecosystems.