Search Results (1,061)

With industrial transformation and the rise in the 15 min community life circle, optimizing walkability and preserving industrial heritage are key to revitalizing former industrial areas. This study, focusing on Shijingshan District in Beijing, proposes a walkability evaluation framework integrating multi-source big data and street-level perception. Using Points of Interest (POI) classification, which refers to the categorization of key urban amenities, pedestrian network modeling, and street view image data, a Walkability Friendliness Index is developed across four dimensions: accessibility, convenience, diversity, and safety. POI data provide insights into the spatial distribution of essential services, while pedestrian network data, derived from OpenStreetMap, model the walkable road network. Street view image data, processed through semantic segmentation, are used to assess the quality and safety of pedestrian pathways. Results indicate that core communities exhibit higher Walkability Friendliness Index scores due to better connectivity and land use diversity, while older and newly developed areas face challenges such as street discontinuity and service gaps. Accordingly, targeted optimization strategies are proposed: enhancing accessibility by repairing fragmented alleys and improving network connectivity; promoting functional diversity through infill commercial and service facilities; upgrading lighting, greenery, and barrier-free infrastructure to ensure safety; and delineating priority zones and balanced enhancement zones for differentiated improvement. This study presents a replicable technical framework encompassing data acquisition, model evaluation, and strategy development for enhancing walkability, providing valuable insights for the revitalization of industrial districts worldwide. Future research will incorporate virtual reality and subjective user feedback to further enhance the adaptability of the model to dynamic spatiotemporal changes. Full article

The integration of photovoltaic (PV) panels in greenhouses enables dual land use, combining crop production with electricity generation. However, PV installations can reduce both the intensity and uniformity of light at the canopy level, potentially affecting crop growth. This study employed computational fluid dynamics (CFD) simulations to evaluate the effects of different layouts of commercial-size thin PV modules—both opaque and semi-transparent—installed at gutter height in greenhouses on irradiance and, in particular, on its distribution within the greenhouse. Achieving a homogeneous distribution of light is critical for effective plant growth beneath photovoltaic systems. The influence of greenhouse size and roof shape on the intensity and uniformity of visible radiation was investigated as well. The results showed that during winter (21 December), irradiance in a mono-span tunnel greenhouse was 4–6% higher than in a multi-span large structure; in summer (21 June), this difference increased to 10–13%. Among the opaque PV layouts tested, the north–south (NS) straight-line arrangement provided the most uniform light distribution, outperforming the checkerboard and east–west (EW) layouts. The EW straight-line layout was the least effective regarding light uniformity. Roof shape (arched vs. pitched) had minimal impact on radiation distribution. Semi-transparent PV modules consistently resulted in 17% higher irradiance and more uniform light distribution than opaque ones. These findings can inform efficient PV deployment strategies in greenhouses to enhance both energy yield and crop productivity. Full article

Urban centers shaped by industrial histories often exhibit complex patterns of land cover change that are not well-captured by standard classification techniques. This study investigates post-industrial urban change in Ponca City, Oklahoma, using remote sensing, unsupervised machine learning, and socioeconomic contextualization. Using a Jupyter Notebook version 7.0.8 environment for Python libraries, Landsat imagery from 1990 to 2020 was analyzed to detect shifts in land cover patterns across a relatively small, heterogeneous landscape. Principal component analysis (PCA) was applied to reduce dimensionality and enhance pixel distinction across multiband reflectance data. Socioeconomic data and historical context were incorporated to interpret changes in land use alongside patterns of industrial reduction and urban redevelopment. Results revealed changes in five distinct land cover classes of urban, vegetative, and industrial land uses, with observable trends aligning with key periods of economic and infrastructural transition. The trends also aligned with socioeconomic changes of the city, with a larger reduction in industrial and commercial land cover than in residential and vegetation cover types. These findings demonstrate the utility of machine learning classification in small-scale, heterogeneous environments and provide a replicable methodological framework for smaller city municipalities to monitor urban change. Full article

Farmers’ land transfer practices optimize the allocation of agricultural resources by transferring them to more efficient operators. This enhances agricultural productivity and advances rural revitalization. However, due to the lack of financial institution outlets in rural areas, the availability of financial services in rural areas is limited, which in turn hinders the transfer of rural land. This study examines the impact of digital financial inclusion, characterized by the deep integration of internet technology and financial services, on farmers’ land transfer behavior in China. The study uses data from the China Family Panel Studies (2012–2022) and provincial digital financial inclusion data. The results show that digital financial inclusion significantly promotes rural land transfer-out. The mechanisms reveal two pathways: (1) digital financial inclusion expands non-agricultural entrepreneurship by easing credit constraints and reducing reliance on land livelihoods; (2) it increases participation in commercial insurance, mitigating risks of land abandonment. Heterogeneity analysis reveals stronger effects in eastern China and among educated households. Theoretically, the study identifies the dual role of financial technology in reshaping rural land markets through credit access and risk management. Practically, it reveals how DFI influences land transfer behavior, providing a basis for the government to formulate policies that combine the two, ultimately enhancing the production capacity, operational efficiency, and market competitiveness of smallholder farmers. The findings offer global insights for developing countries that are leveraging digital finance to activate rural land markets and achieve digital financial inclusion. Full article

Feeding a growing global population requires sustainable, innovative, and cost-effective solutions, especially in light of the environmental damage and nutrient imbalances caused by excessive chemical fertilizer use. Microalgae have gained prominence due to their phylogenetic diversity, physiological adaptability, eco-compatible characteristics, and potential to support regenerative agriculture and mitigate climate change. Functioning as biofertilizers, biostimulants, and bioremediators, microalgae accelerate nutrient cycling, improve soil aggregation through extracellular polymeric substances (EPSs), and stimulate rhizospheric microbial diversity. Empirical studies demonstrate their ability to increase crop yields by 5–25%, reduce chemical nitrogen inputs by up to 50%, and boost both organic carbon content and enzymatic activity in soils. Their application in saline and degraded lands further promotes resilience and ecological regeneration. Microalgal cultivation platforms offer scalable in situ carbon sequestration, converting atmospheric carbon dioxide (CO₂) into biomass with potential downstream vaporization into biofuels, bioplastics, and biochar, aligning with circular economy principles. While the commercial viability of microalgae is challenged by high production costs, technical complexities, and regulatory gaps, recent breakthroughs in cultivation systems, biorefinery integration, and strain optimization highlight promising pathways forward. This review highlights the strategic importance of microalgae in enhancing climate resilience, promoting agricultural sustainability, restoring soil health, and driving global bioeconomic transformation. Full article

The anaerobic co-digestion of agricultural residues emerges as a promising strategy for energy recovery and nutrient recycling within circular agricultural systems. This study aimed to optimize co-digestion parameters for vinegar residue (VR) and cattle manure (CM) using an orthogonal experimental design. Three key variables were investigated which are the co-substrate ratio (VR to CM), feedstock-to-inoculum (F/I) ratio, and total solids (TS) content. Nine experimental combinations were tested to evaluate methane yield, feedstock degradation, and digestate characteristics. Results showed that the optimal condition for methane yield comprised a 2:3 co-substrate ratio, 1:2 F/I ratio, and 20% TS, achieving the highest methane yield of 267.84 mL/g volatile solids (VS) and a vs. degradation rate of 58.65%. Digestate analysis indicated this condition generated the most nutrient-rich liquid digestate and solid digestate, featuring elevated N, P, and K concentrations, acceptable seed germination indices (GI), and moderate humification levels. While total nutrient content did not meet commercial organic fertilizer standards, the digestate is suitable for direct land application in rural settings. This study underscores the need to balance energy recovery and fertilizer quality in anaerobic co-digestion systems, providing practical guidance for decentralized biogas plants seeking to integrate waste treatment with agricultural productivity. Full article

Urban blight and litter are twin issues that significantly affect the quality of life in city neighborhoods. This paper investigates the relationship between blight and litter, commonly overlooked in urban studies literature. We measure the prevalence of blight and litter across block groups in our mapping with a focus on socioeconomic factors, including income levels, crime rates, and land use types (industrial, commercial, and residential) for our case study, Memphis, Tennessee. Using statistical and spatial analytics, as well as data from the Memphis Data Hub and the City of Memphis, we show the prevalence of blight and litter across block groups. GIS was used to map neighborhood-specific blighted structures and their spatial connection to litter accumulation. We also explore the distribution of blight and litter across different land uses. A Pearson correlation value of 0.639 suggests a strong positive relationship between blight and litter at the block group level. Spatial clustering is assessed by Global Moran’s I and Local Moran’s I, identifying neighborhood-level hotspots. The block group is used as the unit of analysis to capture micro-spatial variation and to enable meaningful equity-based insights at the neighborhood level. Our mapping offers practical insights into urban revitalization strategies in deference to per capita income, crime rate, and land use. The findings contribute to urban policy discussions by promoting the joint consideration of blight and litter, helping guide future community-based interventions aimed at alleviating the negative impacts of blight and litter, particularly in disadvantaged neighborhoods. Full article

The urgent need to address the climate crisis demands a swift transition from fossil fuels to renewable energy. Clean hydrogen, produced through ethanol steam reforming (ESR), offers a viable solution. Traditional ESR operates at atmospheric pressure, requiring costly separation and compression of hydrogen. High-pressure ESR, however, improves hydrogen purification, streamlines processes like pressure swing adsorption, and reduces operational costs while enhancing energy efficiency. High-pressure ESR also enables compact reactor designs, minimizing equipment size and land use by compressing reactants into smaller volumes. This study evaluates two nickel-based commercial catalysts, AR-401 and NGPR-2, under high-pressure ESR conditions. Key parameters, including reaction temperature, steam-to-ethanol ratio, and weight hourly space velocity, were optimized. At 30 bars, 700 °C, and a steam-to-ethanol ratio of 9, both catalysts demonstrated complete ethanol conversion, with hydrogen selectivity of 65–70% and yields of 4–4.5 moles of H₂ per mole of ethanol. Raising the temperature to 850 °C improved hydrogen selectivity to 74% and yielded 5.2 moles of H₂ per mole. High-pressure ESR using renewable ethanol provides a scalable, efficient pathway for hydrogen production, supporting sustainable energy solutions. Full article

Cities have become the largest consumers of resources and contributors to pollution due to urbanization. Therefore, measuring quality and maintaining standards have become crucial, as the boundaries of measurements for a city’s environmental quality are vague. This research study followed a qualitative approach to verify the factors affecting city environmental quality and to identify the boundaries of measurements using Sri Lankan cities as a case study. Data analysis was conducted using a thematic analysis approach, which adhered to the qualitative nature of the research. Findings revealed that seven main factors—energy consumption, water consumption, material and resource consumption, land utilization, disaster resilience, education, and governance—play a significant role in maintaining a city’s environmental quality. It was revealed that measuring boundaries can vary according to individual units (such as household, industrial, or commercial buildings) or city boundaries, in order to maintain quality standards. The findings revealed significant considerations for environmental quality performance, highlighting the influence of urban planning, governance, and public awareness on environmental sustainability outcomes in cities. Notably, this study contributes to a deeper understanding of how environmental quality intersects with social well-being in urban planning, affecting the quality of life and equitable access to urban resources. Full article

Food and nutritional insecurity, alongside poverty, remain formidable challenges within smallholder crop–livestock mixed farming systems, predominantly found in Asia and Africa, which are the primary focus of this review. Livestock stands as a crucial asset in these systems, providing food and income for families. However, livestock productivity is often constrained by poor-quality feed, predominantly composed of crop residues. This is compounded by limited access to high-quality forage seeds and the misconception that limited land and water resources should be devoted to cereal production. Furthermore, formal seed supply chains for forages are often underdeveloped or non-existent, making it difficult for farmers to access quality seed. The integration of high-quality legume forages into these systems offers a cost-effective and sustainable solution for improving livestock productivity. These forages provide more nutritious feed and enhance soil fertility through nitrogen fixation, helping to reduce farmers’ reliance on expensive commercial feeds and fertilizers. Success in the adoption of improved forage varieties hinges on participatory approaches that actively engage farmers in varietal selection and evaluation. Such collaboration leads to better adoption rates and increases on-farm productivity, facilitating the establishment of village-based forage seed enterprises (VBFSEs). These enterprises offer a reliable local seed supply of quality seeds, reducing farmers’ dependency on inconsistent national and international seed suppliers. These initiatives not only improve the production of high-quality forage and livestock productivity but also create opportunities for income diversification, contributing to the livelihoods of smallholder farmers. By fostering collaboration and sustainable practices, policymakers and stakeholders, particularly farmers, can build more resilient agricultural systems that support food security and poverty alleviation in rural communities. Full article

As China’s urbanization deepens, the spatial structure of residential areas and land use patterns has undergone profound transformations, with the differentiation of housing prices emerging as a key indicator of urban spatial dynamics and socioeconomic stratification. This study examines the spatial and temporal evolution of residential housing prices in Qingdao’s main urban area over a 20-year period, using data from three representative years (2003, 2013, and 2023) to capture key stages of change. It employs Local Indicators of Spatial Association (LISA) spatial and temporal path and leap analyses, as well as Geographically and Temporally Weighted Regression (GTWR) modeling. The results show that Qingdao’s housing price patterns exhibit distinct spatiotemporal heterogeneity, characterized by multi-level transitions, leapfrog dynamics and strong spatial dependence. The urban center and coastal zones demonstrate positive synergistic growth, while some inland and peripheral areas show negative spatial coupling. Evident is the spatial restructuring from a monocentric to a polycentric pattern, driven by shifts in industrial layout, policy incentives, and transportation infrastructure. Key driving factors, such as community attributes, locational conditions, and amenity support, show differentiated impacts across regions and over time. Business agglomeration and educational resources are primary positive drivers in central districts, whereas natural environments and commercial density play a more complex role in peripheral areas. These findings provide empirical evidence to inform our understanding of housing market dynamics and offer insights into urban planning and the design of equitable policies in transitional urban systems. Full article

Fisheries management in Abu Dhabi has undergone a significant transformation over the past two decades, shifting from an open-access system to a more regulated framework aimed at stock recovery and sustainability. This study evaluates the status of 13 commercially important fish species—accounting for 95% of total landings—using two complementary stock assessment methods: CMSY++, a Bayesian catch-based model, and the Length-Converted Catch Curve (LCCC), a length-based mortality estimation approach. Fisheries-dependent and fisheries-independent data collected from 2001 to 2024 were analyzed to assess trends in biomass, exploitation rates, and spawning stock biomass per recruit (SBR). CMSY++ outputs indicate that in 2005, only 1 out of 13 stocks was sustainable, with biomass (B) above the biomass that can reproduce maximum sustainable yield (BMSY) and fishing mortality (F) below the fishing mortality that gives the maximum sustainable yield (FMSY), and 5 stocks were overexploited. By 2024, seven stocks had recovered to sustainable levels, with biomass at or above BMSY and exploitation rates below FMSY. LCCC results for 2024 further confirm these findings, with most species exhibiting SBR values above the 30% threshold, except for Lethrinus nebulosus (Forsskål, 1775), which remains close to overexploitation limits. The observed stock recovery coincides with effective governance and key fisheries management measures, including effort reduction, gear restrictions, and spatial protections. While most stocks are now within sustainable biological reference points, transboundary species such as Scomberomorus commerson (Lacépède, 1800) require continued regional cooperation for effective management. These findings contribute to ongoing efforts to achieve and maintain fully sustainable fisheries in the Arabian Gulf while aligning with international conservation frameworks, biodiversity protection goals, and climate-resilient fisheries management strategies. Full article

This study examines the spatial dynamics of urban sprawl in the peri-urban areas of Malang Municipality from 2004 to 2024. The findings reveal a rapid and uneven expansion of built-up areas, growing from 1825.87 ha (4%) in 2004 to 8017.22 ha (15.39%) in 2024. The most significant growth occurred in Singosari, Pakis, and Karangploso Districts, driven by proximity to higher education institutions, tourism centers, and commercial zones. Meanwhile, recent development trends in Kedungkandang District suggest emerging southeastern expansion supported by land availability and infrastructure. An analysis using the Landscape Expansion Index (LEI) indicates a transition from diffusion to coalescence phases, characterized by dominant edge-expansion, increasing infill, and persistent outlying patterns. However, discrepancies between spatial plans and actual land use were found, including 677.29 ha of non-built areas, 172.38 ha of which were sustainable agriculture zones converted into built-up land. These inconsistencies highlight the urgent need for stronger land-use control, including the implementation of Urban Growth Boundaries (UGBs) and stricter enforcement of spatial regulations. Future research should explore spatial drivers using logistic regression or spatial modeling approaches to support more sustainable urban planning in peri-urban regions. Full article

This study investigates the aerodynamic performance of a blended multi-winglet configuration installed on the wingtip of a transonic commercial aircraft, focusing on both subsonic and transonic regimes. Conventional single winglets are typically optimized to reduce induced drag during cruise, but multi-winglets have the potential to enhance lift during takeoff and landing. However, their effectiveness in transonic conditions remains insufficiently explored. In this work, a reference Boeing 767 blended winglet was divided into three distinct elements, each retaining the original wingtip airfoil. Computational simulations were conducted to compare single- and multi-winglet configurations under cruise conditions. Additional analyses were performed at subsonic speeds to evaluate lift performance. Under transonic conditions, the multi-winglet configuration exhibited a 1.4% increase in total drag due to a greater projected frontal area. However, it achieved reduced induced drag, attributed to the rearmost winglet’s negative cant angle, which suppresses vortex formation by inhibiting upward airflow. In subsonic flight, lift improved by up to 1.3% due to accelerated flow over the upper surface, enhanced by smaller leading-edge radii and air acceleration through inter-winglet gaps. These findings suggest that multi-winglets outperform single winglets in reducing induced drag during cruise and enhancing lift during takeoff and landing. Full article

Carbon flow tracking and spatial pattern optimization at the scale of urban functional zones are key scientific challenges in achieving carbon neutrality. However, due to the complexity of carbon metabolism processes within urban functional zones, related studies remain limited. To address these scientific challenges, this study, based on the “source–sink–flow” ecosystem services framework, develops an integrated analytical approach at the scale of urban functional zones. The carbon balance is quantified using the CASA model in combination with multi-source data. A network model is employed to trace carbon flow pathways, identify critical nodes and interruption points, and optimize the urban spatial pattern through a low-carbon land use structure model. The research results indicate that the overall carbon balance in Hangzhou exhibits a spatial pattern of “deficit in the center and surplus in the periphery.” The main urban area shows a significant carbon deficit and relatively poor connectivity in the carbon flow network. Carbon sequestration services primarily flow from peripheral areas (such as Fuyang and Yuhang) with green spaces and agricultural functional zones toward high-emission residential–commercial and commercial–public functional zones in the central area. However, due to the interruption of multiple carbon flow paths, the overall carbon flow transmission capacity is significantly constrained. Through spatial optimization, some carbon deficit nodes were successfully converted into carbon surplus nodes, and disrupted carbon flow edges were repaired, particularly in the main urban area, where 369 carbon flow edges were restored, resulting in a significant improvement in the overall transmission efficiency of the carbon flow network. The carbon flow visualization and spatial optimization methods proposed in this paper provide a new perspective for urban carbon metabolism analysis and offer theoretical support for low-carbon city planning practices. Full article