Search Results (8,660)

As a mountain–water city in the upper Yangtze River region, Chongqing is characterized by complex river-valley terrain, dense riverside development, extreme summer heat, high humidity, and frequent calm-wind conditions. Existing studies on waterfront thermal comfort mainly focus on plain cities, whereas mountainous riverside parks remain insufficiently understood. This study investigated summer thermal comfort in three riverside parks in Chongqing—Jiulongtan Park, Coral Park, and Jiangtan Park—through field measurements of air temperature, black globe temperature, wind speed, relative humidity, and Thermal Radiation, combined with thermal sensation vote (TSV) and thermal comfort vote (TCV) surveys. Results showed that the maximum air temperature reached 43.7 °C and the maximum black globe temperature reached 61.6 °C. The hydrophilic layer recorded the highest wind speed (1.64 ± 0.39 m/s), while the elastic layer showed high PET values (36.00–46.10 °C). Regression analysis indicated neutral PET values of 32.49–35.74 °C. Correlation analysis showed that PET, mean thermal sensation vote (MTSV), and mean thermal comfort vote (MTCV) were positively correlated with air temperature, black globe temperature, mean radiant temperature (T_mrt), and relative humidity. In contrast, PET was negatively correlated with wind speed. This study reveals the coupled effects of river-valley terrain, elevation stratification, waterfront microclimate, and landscape elements on outdoor thermal comfort, providing a scientific basis for optimizing shading, ventilation, and hydrophilic spaces in hot-humid mountain–water cities. Full article

To achieve low-carbon and cost-effective operation of multi-park electricity–heat–hydrogen integrated energy systems (EHHSs), this paper proposes a low-carbon dispatch framework based on federated safe reinforcement learning. First, a multi-park EHHS dispatch model is established by considering heterogeneous park characteristics, electricity–heat–hydrogen coupling, stepped carbon trading, and peer-to-peer (P2P) energy trading. Then, to address the coupled challenges of privacy preservation, operational coupling, and safety constraints, the dispatch problem is formulated as a constrained Markov decision process (CMDP). On this basis, a federated safe proximal policy optimization algorithm (FedSafePPO) is developed by integrating PPO, Lagrangian-based safety constraint handling, and federated parameter aggregation. The proposed method enables each park to learn a local dispatch policy from private data while sharing global knowledge without exchanging raw operational data. In addition, an actor–dual-critic architecture is adopted to jointly evaluate economic returns and constraint costs, thereby improving convergence stability and dispatch feasibility. Case studies involving three heterogeneous parks—industrial, commercial, and residential—demonstrate that the proposed method effectively reduces total operating costs and carbon emissions while satisfying system constraints. Compared with PPO, FedPPO, and SafePPO, the proposed FedSafePPO achieves superior low-carbon economic performance, greater training stability, and better adaptability to heterogeneous operating conditions. The results verify the effectiveness and engineering applicability of the proposed method for the low-carbon dispatch of multi-park EHHSs. Full article

Ants are widely used as bioindicators because of their sensitivity to environmental change and their functional roles in ecosystems. This study presents the first comparative analysis of ant communities in two habitats, an agricultural system and a semi-natural forest, within the Natural Park of Montesinho (northeastern Portugal). From May to October 2022, four plots were sampled per habitat: (i) semi-natural oak forest and (ii) chestnut orchard under human management, using five pitfall traps in each plot. A total of 1969 ants were captured, representing 32 species and 15 genera. Traditional chestnut orchards supported more exclusive species and greater functional diversity, dominated by generalist and thermophilic taxa. In contrast, oak forests hosted more specialist and cold-adapted species, which may reflect a higher structural stability. Seasonal variation was more pronounced in chestnut orchards, consistent with disturbance-driven dynamics. The functional composition also differed: chestnut orchards favoured granivores and scavengers, while oak forests supported predators and mutualists. These findings highlight the value of ant communities as sensitive indicators of land use and ecosystem condition in Mediterranean mountain systems. Full article

To address the challenges of significant vehicle parking constraints, limited UAV endurance, and insufficient multi-task coordination efficiency in distribution network inspection, this paper proposes a vehicle–UAV synchronous cooperative inspection task scheduling method based on multi-objective twin delayed deep deterministic policy gradient and nondominated sorting genetic algorithm II (MOTD3-NSGA-II). First, a vehicle–UAV synchronous cooperative inspection model is established by considering staged vehicle repositioning, same-site UAV launch, landing, and retrieval, as well as state-of-charge constraints. On this basis, a multi-objective optimization model is formulated with task coverage, mission completion time, minimum residual state of charge, and load balance as objectives. Then, a bi-level closed-loop solution framework is developed, in which NSGA-II is employed to optimize cooperative parameters and objective preference weights, while the inner-layer MOTD3 learns UAV scheduling policies in a continuous action space. Finally, the proposed method is validated in four simulation scenarios with different task scales and spatial distribution characteristics. The results show that 100% task coverage is achieved in all four scenarios, with mission completion times of 11,109 s, 9693 s, 10,538 s, and 10,721 s, respectively, while the minimum residual state of charge is maintained within 0.28–0.36. The results demonstrate that the proposed method can balance inspection completeness, execution efficiency, energy safety, and cooperative stability, providing a useful reference for intelligent task scheduling in vehicle–UAV cooperative distribution network inspection. Full article

Urban community parks are important public open spaces (POSs) that support residents’ quality of life (QoL) by aiding recreation, social interaction, and physical activity. However, evidence on how to design and assess sustainable POS in Saudi Arabia remains limited, particularly in relation to the country’s hot–arid climate, socio-cultural context, and emerging urban development priorities. This study aims to develop a context-sensitive framework for the design and assessment of sustainable POSs (a scope of urban community parks) in Saudi Arabia using a mixed-methods approach. The study combined: (i) a structured review of the literature on POSs’ sustainability and QoL/subjective well-being (SWB); (ii) naturalistic field observations in two community parks in Al-Khobar (Shells Park and Prince Ibn-Jalawy Park); (iii) an on-site questionnaire survey of park users assessing satisfaction and self-reported well-being (n = 89); and (iv) structured expert interviews to refine and prioritize the framework elements (n = 15). The quantitative analysis included descriptive statistics, Pearson correlation analysis, and reliability testing using Cronbach’s alpha, the Mann–Whitney U test, and the Kruskal–Wallis test to explore the associations between perceived park attributes, user satisfaction, and self-reported well-being. The framework was iteratively refined through triangulation via the literature, field evidence, user feedback, and expert judgement, while expert responses were synthesized using weighted mean scores, simple ranking system, and the Relative Importance Index (RII). The findings indicate that shading and thermal comfort, safety, accessibility, maintenance, and cultural alignment are the most important design priorities in the Saudi Arabian context. The empirical assessment also highlights recurrent shortcomings in the selected parks, particularly inadequate heat mitigation measures, inconsistent maintenance, limited recreational infrastructure, and the weak integration of smart support features. Based on this triangulated evidence, the study proposes a framework comprising nine categories, 43 sub-categories, with 137 indicators organized across environmental, socio-cultural, economic, and smart-enabler considerations. The framework provides a practical and context-sensitive tool for evaluating existing parks, prioritizing interventions, and guiding future community park development in support the Quality-of-Life Programme of Saudi Vision 2030. Full article

The rapid electrification of road transport has increased interest in distributed energy strategies that reduce grid demand and support decarbonization. Vehicle-integrated photovoltaics (VIPV), including vehicle-applied photovoltaic configurations (VAPV), can generate electricity directly on the vehicle. This systematic review examines peer-reviewed VIPV literature published between 2015 and 2026, focusing on the distinction between theoretical photovoltaic generation and practically usable energy. A Scopus search conducted on 2 May 2026 identified 196 records, of which 88 studies were included after screening against predefined criteria. Due to heterogeneity in vehicle types, climates, technologies, modeling assumptions, and reported metrics, no meta-analysis was performed. Instead, the review applies a multi-layered framework covering climate, geometry, thermal effects, electrical mismatch, battery state-of-charge interactions, fleet-scale modeling, economics, and life-cycle implications. The evidence shows that VIPV is technically feasible and can deliver measurable energy yields, especially in high-irradiance regions and vehicles with favorable daytime parking exposure. However, useful contribution depends strongly on curvature losses, dynamic shading, electrical configuration, SOC limits, charging behavior, seasonality, and vehicle energy demand. Therefore, VIPV is best understood as a context-dependent supplementary energy strategy rather than a transformative standalone solution. Its strongest value lies in specific vehicle classes, climates, and usage patterns where on-board generation can reduce charging demand, support operational resilience, or improve distributed self-consumption. The review also proposes minimum reporting requirements for future studies, including annual energy yield, Wh/km contribution, PV area or capacity, mileage assumptions, SOC modeling, and curtailment treatment. The review was not formally registered, and no formal risk-of-bias or certainty assessment was applied. Full article

Existing research on the landscape patterns of urban parks and green spaces demonstrates a disproportionate focus across tiers within China’s urban hierarchy. Numerous studies have concentrated on economically developed first-tier cities, such as Beijing, Shanghai, and Guangzhou. In contrast, medium-to-large non-first-tier cities, especially provincial capitals and emerging cities within the first- and second tiers, have been relatively understudied, although they have received increasing attention in recent years. This bias extends regionally, with studies predominantly examining cities in the more developed central and eastern regions, while less-developed areas and lower-tier cities receive significantly less attention. This study tracks changes in park quantity, spatial concentration, patch structure and driver associations at three planning-related time points. Shenyang provides a distinct cold-region and old industrial city case, shaped by long winters, industrial renewal and outward urban growth. Furthermore, to inform park and green-space planning in Northeast China’s cold-climate cities, exemplified here by Shenyang, a major metropolis with a monsoon-influenced humid continental climate (Köppen Dwa), long cold winters, and relatively short warm summers, we document a shift in park distribution from the urban core to peripheral areas. Based on park vector layers reconstructed from planning documents, remote sensing interpretation and field verification, this study combined spatial analysis, landscape metric calculation and driver-association modeling. ArcGIS Pro was used to identify changes in distribution centers, directional extension and local clustering; FRAGSTATS 4.2 was used to calculate park landscape metrics; and SIMCA-P 14.1 was used to examine the statistical associations between selected landscape indicators and potential driving variables. The results show that the number and total area of parks in central Shenyang increased substantially from 2000 to 2024. Spatially, park distribution became less concentrated in the traditional inner city, while new clusters gradually appeared in peripheral districts and newly developed urban areas. The old urban core remained important, but its dominance weakened as park provision expanded outward. The landscape metric results further indicate that park expansion was accompanied by more irregular patch forms, stronger fragmentation and declining structural continuity. The driver association analysis suggests that climate conditions, population change, industrial restructuring, real estate investment, road construction and urban greening policies were related to different aspects of park landscape change. These associations should be interpreted as statistical relationships rather than direct causal effects. Overall, this study clarifies the spatial restructuring of park green spaces in a cold-region old industrial city and provides planning evidence for improving park connectivity, coordinating green space expansion with urban construction and supporting sustainable park system development in Northeast China. Full article

Property-rights confirmation and registration are widely regarded as an institutional foundation for ecological-product value realization, yet the dynamic mechanism through which registration clarity affects multi-actor cooperation remains insufficiently understood. Using the Yunhe Terraced Fields National Wetland Park in Zhejiang Province as a case, this study develops a tripartite evolutionary-game model involving the local government, farmers, and tourism enterprises. The model incorporates registration clarity into the payoff structure through transaction-cost reduction, compensation realization, and regulatory constraint channels. Parameters are calibrated using gross ecosystem product (GEP) accounting, policy documents, administrative records, and field survey data. Numerical simulations show that clearer registration expands the basin of attraction of cooperative equilibrium and accelerates convergence under the calibrated parameter setting. Government incentives serve as an important external trigger, enterprise participation depends on a feasible balance between cost-sharing and expected returns, and farmers’ ecological protection is crucial for maintaining long-term cooperative stability. The study contributes by transforming registration clarity from a descriptive institutional background into a scenario-based institutional-intensity variable within an evolutionary-game framework. The findings should be interpreted as calibrated simulation evidence rather than direct causal estimates, and they suggest an integrated institutional path linking registration, compensation, transaction-cost reduction, and regulation. Full article

The organic complexation of Cu²⁺ in aquatic systems dominates its chemical speciation, affecting its reactivity and bioavailability. Using voltammetry, we investigated Cu²⁺ organic complexing capacity (CuCC) in atmospheric samples, including water-soluble aerosol fraction, rainwater (wet-only deposition), and bulk deposition (wet and dry deposition), collected in a coastal marine area (National Park Brijuni, Adriatic Sea). The focus was on minimizing analytical interferences from surface-active substances (SAS) that accounted for up to 56% of dissolved organic carbon. Method optimization was performed using model SAS (humic-like substances, fulvic acid, and pollen-derived organic material), resulting in an optimal desorption potential of −1.4 V and the addition of 1 mg/L Triton X-100. Under these conditions, CuCC parameters of average ligand concentration and conditional stability constant of (209.8 ± 6.7) nM and log K = (10.2 ± 0.6) in water-soluble aerosol fraction, (117.1 ± 5.0) nM and log K = (9.6 ± 0.2) in rainwater, and (142.9 ± 4.1) nM and log K = (10.2 ± 0.2) in bulk deposition were determined. Atmospheric inputs represented a source of weak Cu-binding ligands for marine areas. In conclusion, short-term monitoring provided insight into the variability of different atmospheric inputs and offered a methodological basis for future long-term, more comprehensive studies. Full article

Urban green spaces play a key role in supporting biodiversity, climate regulation, and carbon storage in rapidly expanding cities. Urban and peri-urban parks can differ markedly in tree-community structure, floristic diversity, and carbon-storage capacity. The aim of the study was to compare these attributes between an urban and a peri-urban park. The study compared these attributes between an urban park and a peri-urban park in western Mexico using data collected in 500 m² circular plots. Tree structure was assessed through diameter at breast height, height, crown diameter, basal area, and crown projection area, while floristic composition and diversity were evaluated using richness, Shannon, Simpson, Pielou, and Menhinick indices. Aboveground biomass, belowground biomass, and carbon stocks were estimated using generalized allometric equations. A total of 1675 trees belonging to 19 families, 33 genera, and 49 species were recorded. The peri-urban park showed greater structural development, with significantly higher DBH, height, crown diameter, basal area, biomass, and carbon stocks, whereas the urban park supported greater species richness and higher Shannon diversity. Species composition also differed strongly between parks, and carbon storage was concentrated in a reduced number of dominant taxa in each site. DBH was the structural variable most strongly associated with total carbon per tree. These findings show that floristic diversity and carbon-storage capacity do not necessarily increase in parallel and that urban and peri-urban parks can provide contrasting but complementary ecological functions. Full article

Against the backdrop of urbanization and global warming, reducing carbon emissions and achieving carbon neutrality have emerged as focal points in current urban ecological research. Urban green infrastructure (UGI) serves as the primary natural carbon sink within cities; therefore, investigating and optimizing its carbon sequestration services is a crucial step toward realizing carbon neutrality and fostering sustainable urban development. As the core components of urban ecosystems, urban parks provide essential ecosystem services that play a pivotal role in expanding carbon sinks, facilitating energy conservation and emission reduction, and enhancing urban climate resilience. This paper takes 20 parks in Linyi City’s central urban area as examples, systematically quantifies the carbon sequestration effect of urban parks in the central urban area of Linyi City from 2019 to 2024 using methods such as the Carnegie–Ames–Stanford Approach (CASA) and the gravity model, and quantitatively evaluates the equity of urban residents’ access to these services. The study shows that the overall annual average carbon sequestration rate of urban parks in Linyi City’s central area over nearly six years ranges from 202.02 gC·m⁻²·a⁻¹ to 279.31 gC·m⁻²·a⁻¹, while individual park annual averages range from 171.29 to 332.76 gC·m⁻²·a⁻¹, falling within the normal range for cities at the same latitude; in terms of vegetation carbon sequestration capacity, woody plant communities dominate in this region, with annual average carbon sequestration rates approximately 10% higher than those dominated by herbaceous vegetation. In terms of intrinsic activity performance of carbon sequestration, overall, woody-dominated plant communities exhibit greater stability and resilience under extreme weather conditions, experiencing smaller impacts on ecological functions but longer recovery cycles to peak levels. Regarding equity in the supply and demand of ecosystem services, the Gini coefficient in the study area is 0.59, indicating an extremely imbalanced state; within the same park service range, up to 60% of residents do not benefit from carbon sequestration ecosystem services. The urban supply–demand mismatch reveals that approximately 20% of the population resides in high-demand–low-supply areas, experiencing extreme ecological deprivation; only about 13% of the population falls into the high-demand–high-supply category, this group being the high-benefit recipients who enjoy both spatial convenience and high-quality ecological welfare. The theoretical implications for urban green space planning: according to the results, merely expanding park green space area to increase per capita access is myopic and inadvisable in central urban park planning. Instead, greater emphasis should be placed on enhancing ecological service levels beyond basic area requirements, comprehensively improving vegetation quality and ecosystem service capacity of parks. In old urban areas constrained by land use, the hierarchical structure of vegetation should be strengthened, and micro green spaces should have enhanced ecological service capabilities to improve residents’ access rights through higher service quality. In newly developed urban areas, planning should balance quantity and quality to serve more people and alleviate urban ecological pressures. Overall, by quantitatively assessing the carbon sequestration capacity and the socio-spatial equity of ecosystem services provided by urban parks in Linyi City, this study offers robust empirical evidence and methodological tools for sustainable urban planning, ultimately fostering the sustainable development of urban ecosystems. Full article

The Carpathian Mountains are an important hotspot of European biodiversity, where geological history, climatic diversity, and altitudinal heterogeneity have determined a great diversity and endemism of vascular plants. The study was conducted in the national park of Piatra Craiului, a distinctive limestone massif in the Southern Carpathians. The dataset included 731 vascular plant species from the study area, of which 35 taxa are endemic to the Carpathians (of the 47 reported in this area), and 18 are classified as species of conservation interest in the Management Plan of the National Park (MP). The distribution of endemic species showed different habitat and altitudinal specificity across 15 vegetation types, including 14 Natura 2000 habitats and one outside the EUR 28 classification. The endemic species showed a bell-shaped altitudinal distribution, peaking at 1600–1700 m and concentrated in high-altitude open habitats rather than forested mid-elevations. The PCA separates endemic species along a main gradient from open, disturbed, light-rich habitats to stable, nutrient- and moisture-rich forest environments, and a secondary gradient related to temperature and soil reaction linked to altitude. Endemic species are predominantly associated with calcareous rocky and grassland habitats and are almost absent from mesophilic and hygrophilous habitats. A positive association between endemic species frequency and the total number of species of conservation interest per plot was detected. We concluded that species of conservation interest (such endemic species) are unevenly distributed among habitat types in the Carpathians, with the greatest diversity and abundance in subalpine rocky and grassland habitats, shaped by altitude and isolation. Although the threatened endemic species are not officially listed by national law, they are indirectly protected by management zonation. In Piatra Craiului the richest habitats in endemic species are included in the designated zones of the national park with the highest protection regime, according to the National Park’s Management Plan. Moreover, this territory is included in a Natura 2000 site (ROSAC0194 Piatra Craiului) ensuring an additional level of protection for the habitats where endemic species are found. Full article

The intensification of urbanization and the environmental crisis highlight the need for new paradigms of sustainable urban development, in which mobility plays a central role. This article analyzes sustainable urban mobility initiatives in Latin American knowledge territories through a comparative framework that integrates Knowledge-Based Urban Development (KBUD) and urban circularity principles. Grounded in the Fourth-Generation Knowledge Territories (TC4) perspective, the study focuses on governance models and social participation as drivers of transformative mobility practices. Methodologically, it adopts a qualitative and exploratory case study approach, combining primary data from field visits with secondary sources such as legislation, institutional documents, and technical reports. Despite the proliferation of science parks and innovation districts in Latin America, little is known about how governance and social participation shape sustainable mobility initiatives in these contexts, particularly when analyzed through the combined lenses of KBUD and urban circularity. The comparative analysis reveals varying degrees of openness and limitations in urban mobility governance across the three territories selected (distritotec—Mexico, Parque Patricios—Argentina, and Porto Digital—Brazil). The findings reveal distinct governance configurations and degrees of alignment with circular mobility principles. Distritotec stands out for its multistakeholder governance and community-led mobility initiatives, reflecting efforts to operationalize the quintuple helix model. Parque Patricios shows fragmented integration between infrastructure improvements and participatory planning, while Porto Digital presents limited articulation between innovation policies and sustainable mobility, with centralized governance and low public engagement. Persistent challenges observed throughout the cases include the weak institutionalization of citizen participation, insufficient strategies to disincentivize private car use, and a lack of data governance mechanisms. Full article

This study applies the Actor-Centered Power (ACP) framework to analyze urban green-space governance in three Asian cities, focusing on how power is distributed and exercised among actors in the management of their representative multipurpose parks: Seoul Forest in Seoul, Da’an Forest Park in Taipei, and Yoyogi Park in Tokyo. Conventionally used in large-scale forest governance in the Global South, ACP is extended here to East Asian cities of the Global North. This can provide nascent insight into how coercion, (dis)incentives, and information operate across different institutions. The study found that the initial formation of the parks was driven by potent actors through coercive measures in all three cities. While Seoul maintains centralized statutory governance under the national act, Taipei adopts a decentralized governance model that foregrounds subordinate actors, notably exemplified by the higher education-oriented foundation. This organization promotes citizen science involvement and community-based stewardship. Tokyo, by contrast, uses a public–private partnership model that supports private sector commercial collaboration. This comparative case study demonstrates that the ACP framework is well-suited for analyzing urban green-space governance, as it distinguishes between power subjects (potentates and subordinates) and power sources (coercion, incentives, and information), providing theoretical and managerial implications. Through the lens of the ACP framework, this study argues that distinct institutional arrangements produce divergent power configurations for urban green-space management even within similarly developed urban contexts. Full article

Urban regeneration is critical for addressing contemporary urban challenges, yet its complexity arises from the dynamic interactions among different participants’ preference and strategic behavior factors, making it a multi-agent system driven by strategic behaviors. This study, based on a Chinese urban regeneration case, develops a dynamic evolutionary game model for industrial park renewal to explore the strategic interactions among three key stakeholders: government, social capital, and property owners. The findings reveal three insights: Firstly, the probabilities of social capital participation and property owner cooperation exhibit opposing trends, highlighting conflicting incentives. Secondly, social capital participation follows an inverted U-shaped trajectory with investment ratios, reflecting a strategic trade-off between risk and control; further robustness checks incorporating time delays and phased investments confirm that the curvature of this trajectory is highly sensitive to the project’s development cycle. Thirdly, lower land repayment costs, higher rental income, greater project returns, and a higher profit-sharing ratio promote cooperative strategies among property owners, though this effect remains marginal. The study further demonstrates that non-cooperative behavior among property owners results in a single evolutionary stable strategy (1, 1, 0) where the government repurchases land property rights, and social capital acquires these rights for redevelopment. The findings suggest that this conclusion applies specifically to industrial park renewal in urban centers held by property owners in cities, where it is government-led facilitation, with property owners exiting and social capital entering simultaneously, thereby ensuring alignment of multi-agent strategic behavior in China. Full article