Search Results (3,247)

This study examines the interconnectedness of African stock markets during three major global crises: the 2008 Global Financial Crisis (GFC), the COVID-19 pandemic, and the Russia–Ukraine conflict. We use daily stock index data from 2007 to 2023 for ten African countries and apply a Time-Varying Parameter Vector Autoregressive (TVP-VAR) model. The results reveal that volatility connectedness among African markets intensified during all three crises, peaking during the COVID-19 pandemic followed by the 2008 GFC and the Russia–Ukraine conflict. Short-term connectedness consistently exceeded long-term connectedness across all crises. South Africa and Egypt acted as dominant transmitters of volatility, highlighting their systemic importance, while Morocco showed increased influence during the COVID-19 pandemic. These findings suggest that African markets are more globally integrated than previously assumed, making them vulnerable to external shocks. Policy implications include the need for stronger regional financial cooperation, the development of early warning systems, and enhanced intra-African investment to improve market resilience and reduce contagion risk. Full article

Against the backdrop of the steady advancement of the national rural revitalization strategy and the dual-carbon goals, the low-carbon transformation of rural energy systems is of critical importance. This study first proposes a comprehensive architecture for rural energy supply systems, incorporating four key dimensions: investment, system configuration, user demand, and policy support. Leveraging the abundant wind, solar, and biomass resources available in rural areas, a low-carbon optimization model for rural energy system operation is developed. The model accounts for diverse load characteristics and the integration of elevated water towers, which serve both energy storage and agricultural functions. The optimization framework targets the multi-energy demands of rural production and daily life—including electricity, heating, cooling, and gas—and incorporates the stochastic nature of wind and solar generation. To address renewable energy uncertainty, the Fisher optimal segmentation method is employed to extract representative scenarios. A representative rural region in China is used as the case study, and the system’s performance is evaluated across multiple scenarios using the Gurobi solver. The objective functions include maximizing clean energy benefits and minimizing carbon emissions. Within the system, flexible resources participate in demand response based on their specific response characteristics, thereby enhancing the overall decarbonization level. The energy storage aggregator improves renewable energy utilization and gains economic returns by charging and discharging surplus wind and solar power. The elevated water tower contributes to renewable energy absorption by storing and releasing water, while also supporting irrigation via a drip system. The simulation results demonstrate that the proposed clean energy system and its associated operational strategy significantly enhance the low-carbon performance of rural energy consumption while improving the economic efficiency of the energy system. Full article

Geothermal resources are abundant in China and are distributed mainly in the eastern region where energy demand is high, especially in Tianjin. However, a significant disparity remains between the actual heating area and the potential heatable area of geothermal resources in Tianjin, which indicates the vast untapped potential for development and utilization in the region. In this study, we reviewed the history and current status of geothermal development in Tianjin. We further analyzed the factors affecting the development and utilization of geothermal heat in Tianjin. Subsequently, we constructed a system dynamics (SD) model of geothermal development and utilization in Tianjin. We developed four scenarios, including baseline, policy incentives, technological progress, and economic inputs. The results of the multiscenario forecasts and sensitivity analyses of the SD model showed the following: Tianjin will go through four stages of geothermal development and utilization in the future. Policy support and economic investment were the two main factors influencing the development of geothermal energy, and the influence of technological progress was comparatively smaller. Based on the above results, we proposed recommendations to promote sustainable development of geothermal energy in Tianjin according to three aspects: policy mechanism, economic investment, and technological progress. Full article

The rapid expansion of economic globalization and trade has led to a sharp increase in the shipping investment risks currently faced by cities around the world. This study aims to explore the risk warning mechanism of shipping input under public health events to establish an effective risk warning method. This would enable the rapid identification of potential risk inputs and the implementation of targeted prevention and control measures to ensure public health and safety. This study investigates the mechanisms of both intra-regional and cross-border risk transmission within shipping networks. It establishes a transmission dynamics model (termed the SEIR-SEI model) incorporating climatic, economic, and health factors to analyze the potential inherent risks of regional shipping nodes. It uses the TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) model, modified by the entropy weight method, to calculate the importance of nodes in the shipping network. This comprehensive approach considers the network’s clustering coefficient, betweenness centrality, closeness centrality, degree centrality, and eigenvector centrality. To validate the practicality of the model, this study selects shipping data with Shanghai, China, as the destination node to conduct simulation computations of different risk propagation chains. The findings demonstrate that overall risk transmission is determined by the joint influence of a node’s inherent risks and propagation probabilities. This study not only clarifies the process of cross-border transmission of public health events through the shipping network between cities of different countries, but also provides insights for the application of shipping input risk assessment systems, enriching the academic research on logistics network propagation. Full article

Background: This study compares the cost-utility, visual acuity, and humanistic outcomes of phacoemulsification surgery performed during international outreach campaigns to outcomes in the U.S. Objective: Humanitarian organizations frequently perform cataract surgeries in underserved regions, yet the outcomes of phacoemulsification in these settings remain unexplored. This study aims to compare the visual acuity outcomes, quality-of-life outcomes, and cost of phacoemulsification surgery during international outreach campaigns with those in the U.S. Methods: This retrospective review analyzed 344 cases from Women for World Health (W4WH) missions and 305 consecutive cases from the academic practice of the lead surgeon of W4WH in the US. The pre-operative (pre-op) visual acuity, post-operative (post-op) visual acuity at day 1, and best-corrected visual acuity (BCVA) at post-op month 1 were compared to baseline. The change in visual acuity was compared between the two groups. Complication rates, cost per case, and quality-of-life measures were evaluated for the mission group compared to cataract surgery outcomes in the developed world. Results: The mission cohort had worse baseline visual acuity than the U.S. cohort (1.36 logMAR vs. 0.50 logMAR, p < 0.0001) and showed greater mean improvement (1.24 logMAR vs. 0.35 logMAR, p < 0.0001). Both cohorts achieved similar BCVA at post-op month 1 (0.13 logMAR). The cost for the mission group was USD 276 per surgery. A total of 93.94% of patients in the mission group achieved a BCVA of 20/40 or better, which is comparable to the U.S. outcomes. Conclusions: The dramatic impact, immediacy, and enduring effect of cataract surgery using phacoemusification on quality of life, mental health, and economic return on investment make it the ideal procedure for humanitarian settings. Considering all of the available metrics, our data support the continued expansion of humanitarian efforts by cataract surgery organizations worldwide. Full article

A high level of urbanization, the growing role of cities, and the increasing urban population have led to a rise in the relevance of the problem of selecting investment projects in urban construction. Along with the usual factors considered in such a selection, regional peculiarities of conducting economic activity in the field of urban construction are gaining particular importance. The necessity of taking them into account requires an improvement in decision-making methods. This study develops a multi-stage adaptive method for multi-criteria project selection in urban construction. The method integrates regulatory requirements, the customer’s vision, and retrospective data on previously implemented projects in the region. It comprises the following sequential stages: the elimination of projects that do not meet the requirements; the construction of integral criteria (weighting functions) using logarithmic transformation; and an iterative reduction in the set of criteria. An experimental verification of the developed method demonstrated its application and revealed its potential for practical use. The proposed method can be effectively employed in urban planning systems and the smart management of urban spaces. Full article

Karst topography comprises a fragile ecological environment with a significant potential for carbon sequestration. It is characterized by severe rocky desertification, particularly in China’s karst fault basin. Therefore, there is a crucial need to scientifically evaluate the variations in carbon storage over time and space in this area to ensure effective land space planning and regional ecological security, especially considering the dual carbon target. Using land use data (1985–2020) from the karst fault basin in Southwest China, the study employed the InVEST model to evaluate temporal and spatial variations in carbon storage. A time span of 35 years was examined, and predictions regarding carbon storage in 2050 were formulated under three different conditions: natural evolution, ecological protection, and cultivated land protection. These predictions were based on natural, social, and economic driving factors. The results revealed a fluctuating downward trend in regards to carbon storage in the study area from 1985 to 2020, with a total decrease of 2.1 × 10⁶ t. After 2000, there has been significant improvement in the dynamic degree of land use for forest land, grassland, and construction land compared to the levels before 2000. Additionally, many land use types with high carbon density transitioned into those with lower carbon density. Spatially, the carbon density in the karst fault basin was higher in the north and lower in the central and southern basins. At the county spatial scale, except for the northern and central parts of the study area, there was a decrease in total carbon storage in the remaining counties. By 2050, under the ecological protection scenario, total carbon storage is projected to increase by approximately 6 × 10⁶ t, whereas under the natural evolution and cultivated land protection scenarios, it is expected to decrease by 2 × 10⁶ t and 3 × 10⁶ t, respectively. Specifically, under the natural evolution scenario, only five counties will experience an increase in carbon storage, while the other counties will witness a decrease. The findings of this study offer a scientific basis for enhancing ecosystem carbon services through land management practices and the control of rocky desertification in the karst fault basin. They can inform decision-making processes regarding carbon sequestration, ecosystem restoration, and sustainable land use planning in the region. Full article

Ensuring water resources for livestock production in Kazakhstan presents a multifaceted challenge. Pastoral systems in Southern Kazakhstan are facing a critical groundwater shortage, with 56.5% of pastures currently unused due to limited water access, jeopardizing around 2 million head of livestock and the region’s food security. This study presents the first comprehensive groundwater assessment in over 40 years, integrating hydrochemical analysis (55 samples) and field surveys conducted in the Almaty and Zhetysu regions. Key findings include: the total water demand for livestock is estimated at 53,735 thousand m³/year, with approximately 40% of samples exceeding WHO guidelines for total mineralization. It was determined that 45% of exploitable groundwater reserves in the Almaty region and 15–17% in the Zhetysu region are suitable for irrigation. This study also provides updated hydrogeological data, identifying three priority aquifer systems. A novel Groundwater Sustainability Index for pastoral zones of Central Asia is introduced, demonstrating that strategic aquifer development could expand watered pastureland by 30–40%. These findings directly inform Kazakhstan’s Agricultural Development Plan through 2030 and provide a replicable framework for sustainable water management in arid regions. With 69,836 rural residents currently lacking access to safe water, our results underscore the urgent need for infrastructure investment to meet SDG 6 targets (ensure availability and sustainable management of water and sanitation for all). Full article

Research on woodland ecosystem services is the premise of the formulation of regional woodland policies and ecological protection measures in a new round of woodland protection utilization planning. Based on remote-sensing images and socioeconomic data, this study used the InVEST model, geographical detectors, Spearman correlation analysis, and a coupling coordination degree model to evaluate the spatiotemporal changes, driving factors, and trade-off/synergies relationship of habitat quality (HQ), soil conservation (SC), water conservation (WC), and carbon storage (CS) in the woodland of Zhangjiajie City in 1995, 2005, 2015, and 2022. The results show the following: (1) HQ significantly decreased, SC and WC fluctuated and decreased, and CS continued to increase. (2) Natural factors were predominant, and other factors and natural factors interact to increase the driving effect. (3) The four services were dominated by weak synergy, but SC and CS turned into weak trade-offs in 2022. These research results can provide theoretical support for the optimization of the tourism development model, the formulation of ecological compensation policies, and the high-quality sustainable development of woodland in Zhangjiajie City, and provide a case study of the ecological management of world natural heritage sites. Full article

The development of shallow geothermal energy projects in southern China can meet the demand for regional heating and cooling energy and carbon emission reduction. However, research on constructing evaluation models for the development potential of shallow geothermal energy projects needs to be expanded. Therefore, this study adopted a hierarchical analysis method to construct a project development potential evaluation model based on the four aspects of resource endowment, economic evaluation, environmental impact, and social support for the shallow geothermal energy heating and cooling project (vertical buried pipe heat exchange system) in southern China and carried out case application and evaluation verification. The results of the study show that: (a) the weights of the four primary indicators for evaluating the development potential of shallow geothermal energy projects in southern China were resource endowment (0.3960) > economic evaluation (0.2847) > social support (0.1725) > environmental impact (0.1468); (b) four secondary indicators, namely heat exchange performance, incentive and supportive policies, geotechnical and thermal-physical parameters, and groundwater conditions, were more important; (c) the case evaluation score was 6.2911, and case application and evaluation verification were carried out. For projects with good potential for investment, contrary to the single financial NPV index evaluation results, our results are more in line with the actual operation results of the project. Thus, this evaluation system can provide a more comprehensive reference for shallow geothermal energy development and investment decision-making. Full article

China is one of the world’s leading producers and exporters of wood-based panels and plays a crucial role in ensuring a stable global supply of wood products. But China’s wood product exports have recently diminished, potentially due to the retraction of foreign investment. This behavior remains unexamined mechanistically in the current literature. This study investigates the impact of FDI on the export performance of China’s wood processing industry and explores the potential for leveraging foreign investment to reverse the downward trend in export growth. Our findings indicate that FDI alleviates export constraints by enhancing wood resource efficiency, which suggests a substantive response to industry challenges rather than a mere strategic adjustment. However, FDI inflows have decreased in recent years, negatively affecting export performance and highlighting the need for policy improvements. We further examine the differential effects of FDI on exports across port and non-port regions, given that the urgency of attracting FDI varies spatially. Our analysis reveals that the export spillover effect of FDI in port areas is approximately 165% higher than in non-port areas, largely due to China’s high dependence on wood product imports. In regions with extensive artificial forests, the impact is lower, possibly due to a stronger focus on domestic markets. In particular, Eastern China, benefiting from early market liberalization and a history of successful foreign collaborations, demonstrates significant improvements in export performance. To mitigate the export pressures on China’s wood processing industry, we recommend targeted industrial policies, particularly for port areas, to attract high-quality FDI that supports global supply chain stability and sustainable development. Full article

The Raglan mining site in northern Quebec relies on diesel for electricity and heat generation, resulting in annual emissions of 105,500 tons of CO₂ equivalent. This study investigates the feasibility of decarbonizing the site’s power generation system by integrating a renewable energy network of wind turbines and a pumped hydro storage plant (PHSP). It uniquely integrates PHSP modeling with a dynamic analysis of variable wind speeds and extreme climatic conditions, providing a novel perspective on the feasibility of renewable energy systems in remote northern regions. MATLAB R2024b-based simulations assessed the hybrid system’s technical and economic performance. The proposed system, incorporating a wind farm and PHSP, reduces greenhouse gas (GHG) emissions by 50%, avoiding 68,500 tons of CO₂ equivalent annually, and lowers diesel consumption significantly. The total investment costs are estimated at 2080 CAD/kW for the wind farm and 3720 CAD/kW for the PHSP, with 17.3 CAD/MWh and 72.5 CAD/kW-year operational costs, respectively. The study demonstrates a renewable energy share of 52.2% in the energy mix, with a payback period of approximately 11 years and substantial long-term cost savings. These findings highlight the potential of hybrid renewable energy systems to decarbonize remote, off-grid industrial operations and provide a scalable framework for similar projects globally. Full article

As an important carrier for the application of digital technologies, digital infrastructure plays a crucial role in promoting the digital transformation of the grain system and ensuring food security in the current era. This study utilizes panel data from 31 provinces (municipalities) in China, spanning the years from 2006 to 2022, and constructs a comprehensive evaluation index system for grain system resilience, grounded in its core components of resistance, recovery, and transformation. The grain system resilience index is measured using the entropy method. A spatial Durbin model is employed to estimate the impact of digital infrastructure on grain system resilience, and a panel threshold model is used to analyze the nonlinear effects of digital infrastructure on grain system resilience. The research findings are as follows: (1) Both the direct and spatial spillover effects of digital infrastructure on grain system resilience are significantly positive, but considerable regional heterogeneity is observed. Due to differences in economic development levels, digital infrastructure investments, and policy priorities, the indirect and total effects of digital infrastructure on food system resilience are more pronounced in the southeast region, whereas the direct effects are more significant in the northwest region. (2) The threshold regression results show that when market integration is below the threshold value, the estimated coefficient of digital infrastructure is 0.2242, which is significant at the 1% significance level. When market integration is above the threshold value, the estimated coefficient of digital infrastructure is 0.0790, which is also significant at the 1% significance level. However, its regression coefficient significantly decreases, indicating that the impact of digital infrastructure on food system resilience will weaken as the degree of market integration increases. (3) The analysis of the attenuation boundary of spatial spillover effects shows that within a distance of 225 km, the estimated coefficients of the indirect effects of digital infrastructure on grain system resilience are positive and statistically significant at least at the 10% significance level. However, beyond 225 km, the regression coefficients become negative and insignificant, indicating that the effective boundary of the spillover effect of digital infrastructure on grain system resilience is 225 km, after which the spillover effect gradually diminishes. Based on these findings, it is recommended that the southeast region further strengthen regional digital governance collaboration to maximize spillover effects, whereas the northwest region should prioritize improving digital infrastructure and introduce digital technologies through models such as an “enclave economy” to bridge the digital divide. This study reveals the impact of digital infrastructure on grain system resilience and provides a new perspective for scientifically evaluating the spatial spillover effects of digital infrastructure. Full article

Rural areas face increasing threats from water-related disasters yet often lack the infrastructure and resources available in urban areas for effective disaster response and recovery. Understanding and improving rural resilience—the ability to withstand and recover from disasters—is critical for sustainable rural development, especially under pressures from the climate. This study introduces a practical, indicator-based framework to evaluate rural resilience by analyzing five key aspects: stability, hazards, exposure, vulnerability, and adaptability. Using Zhejiang Province in China as a case study, we examined changes in rural resilience from 2000 to 2020. Our findings reveal that regions with a strong economic foundation, diversified livelihoods, and well-developed healthcare and education infrastructure exhibit higher resilience, while those with high exposure to hazards and economic dependency on agriculture remain vulnerable. The study highlights the crucial role of adaptive capacity in driving long-term resilience, emphasizing targeted investments in rural healthcare, education, infrastructure, and economic diversification. By providing data-driven insights, this research contributes to SDG 11 by offering practical strategies for policymakers and local communities to enhance disaster preparedness and rural sustainability. Moreover, the framework developed here can be adapted and applied to other rural regions facing similar hazards globally, enhancing disaster preparedness and promoting sustainable rural development. Full article

This study evaluates the applicability of the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model for assessing wildfire-induced changes in water-related ecosystem services at a localized scale. Wildfires significantly alter hydrological processes by reducing vegetation cover, which in turn affects water-yield dynamics. To quantify these changes, we applied the InVEST annual water-yield model to a 4.95 km² wildfire-affected area and validated its outputs against the physically based SWAT model. The study utilized Sentinel-2 imagery to create pre- and post-wildfire land cover maps, which served as key inputs for the InVEST model. The results showed a 7.05% increase in water yield after the wildfire. Validation using SWAT confirmed that InVEST could capture localized hydrological changes with accuracy. While InVEST simplifies hydrological processes by relying primarily on land cover data, it remains a valuable tool for rapid and low-resource assessments in wildfire-prone regions. This study highlights the potential of InVEST for rapid post-fire evaluations, offering a practical decision-support model for post-fire land and water resource management in the context of climate change. Full article