Search Results (688)

This study compares two policy instruments for decarbonizing China’s seafood exports to the EU and UK over 10 years using a recursive dynamic computable general equilibrium model. One instrument applies tariff-like carbon surcharges on embedded emissions at the border. The other recognises certified low-carbon production through tiered rate reductions or exemptions. The model constructs product-level carbon cost wedges for processing electricity, aluminium packaging, and cold-chain operations, then transmits them to border prices through pass-through and to import volumes through Armington demand. These mechanisms operate inside a dynamic setting with capital accumulation, learning, and technology adoption. We evaluate processed tuna, shrimp, whitefish, and fresh tilapia to reflect differences in energy use, packaging intensity, and cold-chain reliance. Results show that certification, especially when paired with targeted domestic green finance or tax offsets, speeds adoption of cleaner power and refrigerants and preserves market share better than uniform surcharges. Effects differ between coastal and inland production hubs, supporting location-specific policy bundles. Sensitivity analysis varies carbon prices, adoption speeds, and certification coverage within stated parameter ranges. We report trade, export revenue, emissions, investment, and welfare outcomes and identify product and channel drivers of exposure. Full article

As consumer attitudes shift, non-alcoholic and low-alcohol beers (NABLABs) have grown rapidly in popularity. This has driven interest in biological production methods that avoid the cost and flavor damage associated with post-fermentation dealcoholization. This review focuses on how barley wort composition and process conditions shape the metabolism of maltose- and maltotriose-negative non-Saccharomyces yeasts (NSYs), and how this, in turn, affects ethanol yield, flavor, and aroma in NABLABs. Key sections examine differences in carbohydrate utilization between Saccharomyces and NSYs, the influence of oxygen and Crabtree/Kluyver effects on carbon flux, and the roles of glycerol and organic acid formation as alternate carbon sinks that also contribute to mouthfeel, sweetness perception, and acidity. Particular attention is given to mashing strategies and enzyme additions used to redesign wort sugar profiles for NSYs, including high-temperature, low-gravity mashes and exogenous amyloglucosidase to increase glucose while limiting maltose and ethanol formation. The review also summarizes how the NSY-driven production of esters, higher alcohols, and the biotransformation of hop-derived precursors can offset excessive sweetness and “worty” off-flavors that commonly affect NABLABs. The use of NSYs opens an exciting array of opportunities for brewers to make NABLABs; however, challenges remain. Saccharomyces yeasts have centuries of brewing experience behind them and the adaptations needed for effective use of NSYs are still in development. Fundamentally, the challenge for NABLAB brewers using biological methods is to balance the desirable effects of fermentation while maintaining ethanol levels below the target threshold. This review outlines those challenges in detail and examines some of the approaches that are being used to solve them. Full article

Fluoride (F⁻) contamination in deep groundwater threatens drinking water security, yet its enrichment is commonly governed by coupled nonlinear hydrogeochemical feedbacks that are difficult to resolve with linear diagnostics alone. Here, we integrate an explainable deep learning framework (HydroAttentionNet + SHAP) with thermodynamic and mass-conservative inverse modeling (PHREEQC) to quantitatively link data-driven thresholds to mineral water processes in a multi-aquifer system. Using 258 deep-well samples, we delineate a robust evolution pathway from background to ultra-high-fluoride (Ultra-High F⁻, ≥1.5 mg/L) waters. HydroAttentionNet achieves strong predictive skill (R² = 0.77) and reveals a clear mechanistic tipping behavior: alkalinity (HCO₃⁻/CO₃²⁻) is the primary trigger for F⁻ activation, while progressive Na+ enrichment and Ca²⁺ depletion act as amplifiers by suppressing a(Ca²⁺) and weakening fluorite precipitation capacity. PHREEQC simulations confirm a coupled “salinization–decalcification–fluoridation” loop in which (i) evaporite dissolution elevates ionic strength (salt effect) and supplies Na⁺ to promote Na–Ca exchange, and (ii) carbonate re-equilibration drives calcite precipitation as an efficient Ca sink, offsetting ~45.8% of Ca²⁺ inputs; together, these processes maintain fluorite undersaturation and sustain net fluorite dissolution, contributing 56.6% of newly added dissolved F⁻ in evolved end-members. Monte Carlo health risk assessment (10,000 iterations) indicates substantial intergenerational inequity: 67.9% of children exceed the non-carcinogenic risk threshold (HQ > 1), compared with 29.3% of adults. Sensitivity analysis identifies source-water fluoride concentration as the dominant driver (Spearman r = 0.93), implying that supply-side interventions (defluoridation, well-screen optimization, and blending with low-F sources) are substantially more effective than behavioral measures. Full article

Ecological network optimization can enhance ecological connectivity, regional ecological stability, and carbon sink capacity. Current research on ecological networks employs single-perspective optimization, which overlooks the synergistic requirements between network topological characteristics and the dual carbon goals. It lacks a comprehensive, systemic optimization framework. Focusing on the Beijing–Tianjin–Hebei region, the work constructs an ecological network by integrating ecosystem services, morphological spatial pattern analysis (MSPA), and circuit theory. A framework integrating barrier removal, structural robustness, and carbon sink enhancement is proposed, incorporating ecological barrier identification, complex network theory, and carbon offset patterns for multi-objective structural and functional optimization. The optimized network is evaluated using structural metrics, robustness analysis, and carbon sequestration validation. The network comprises 41 ecological sources and 102 corridors, exhibiting a dense northwest and sparse southeast distribution. Ecological barriers totaling 565.56 km² are removed to improve connectivity in the region. An edge-addition strategy introduces 12 nodes and 49 edges, enhancing connectivity, stability, and carbon sink capacity. Restoration priorities are set with the phased objectives of removing barriers, connecting topological weak points, and optimizing low-value carbon offset areas. Shifting the focus from structural connectivity to integrated function, the work contributes a methodological framework for advancing ecological security and carbon neutrality in urban agglomerations. Full article

This study investigates the psychological mechanisms underlying tourists’ carbon offset behavior in air travel by distinguishing between offset choice (OC) and offset spending (OS). Grounded in the Value–Belief–Norm (VBN) framework, the model integrates Environmental Value and Literacy (EVL), Green Identity and Social Motives (GISM), Trust and Risk Perception (TRP), Personal Norm Activation (PNA), and Perceived Effectiveness (PEF). Data were collected onsite from 500 international and domestic tourists at Suvarnabhumi International Airport, Thailand, between June and July 2025, and analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM). The results indicate that EVL and GISM significantly enhance both PNA and PEF, which in turn exert strong positive effects on OC and OS. PNA emerges as the strongest predictor of both participation and financial commitment, highlighting the central role of moral obligation in motivating carbon offset behavior. While TRP significantly strengthens personal moral norms, its direct effect on Perceived Effectiveness is not significant, suggesting that trust primarily operates through ethical pathways rather than cognitive evaluations of program effectiveness. By distinguishing between participation decisions and spending behavior, this study extends VBN theory to the context of carbon offsets in aviation and demonstrates the mediating roles of moral norms and Perceived Effectiveness in translating environmental values and social identity into compensatory climate action. The findings offer practical implications for airlines and policymakers, emphasizing the importance of moral framing, transparency, and social identity engagement to promote voluntary carbon offset adoption in emerging carbon markets. Full article

Digital services trade is often viewed as a pathway to lower carbon intensity by reducing reliance on carbon-intensive physical trade. However, its environmental benefits may depend critically on the regulatory environments governing cross-border digital interactions. Integrating institutional distance theory with environmental economics, this study examines how regulatory divergence in digital services trade shapes the carbon intensity of international trade. Using bilateral trade data and country-level measures of digital services trade regulations, renewable energy capacity, and environmental policy rigor, we analyze the effects of digital regulatory gaps on carbon emissions embodied in exports. The results show that greater regulatory divergence significantly increases both total carbon emissions and export carbon intensity. The analysis further reveals that the scale effect associated with increased trade volume dominates the technique effect, such that the potential environmental benefits of digitalization are frequently offset by structural inefficiencies and compliance costs induced by regulatory fragmentation. Moreover, exporters’ renewable energy capability amplifies—rather than mitigates—the carbon-intensity-increasing effect of digital regulatory gaps, indicating that institutional misalignment imposes higher environmental opportunity costs on countries with greater low-carbon potential. By contrast, environmental policy rigor in importing countries does not significantly attenuate these effects. Overall, the findings highlight regulatory alignment as a critical condition for realizing the environmental benefits of digital trade. Full article

We report a dual-readout self-resetting CMOS image sensor that achieves a signal-to-noise ratio (SNR) exceeding 70 dB and resolves sub-percent optical contrast variations by effectivly suppressing reset artifacts. The proposed sensor employs a Dual-Readout architecture with two independent scanners operating with a temporal offset; while one readout system is in the self-reset “dead time”, the other remains active, thereby physically ensuring continuous data acquisition. To minimize pixel area while achieving high reconstruction accuracy, a minimum frame-to-frame difference algorithm is utilized for signal restoration without requiring in-pixel counters. A prototype chip fabricated in a 0.35-$\mathsf{\mu }$m process demonstrated SNR characteristics near the shot-noise limit, with a peak SNR exceeding 70 dB. Vascular phantom experiments using a carbon black suspension successfully visualized ±0.25% contrast fluctuations—dynamic signals previously undetectable by conventional sensors. This device provides a powerful platform for high-precision bio-imaging applications, including brain surface blood flow monitoring, where both wide dynamic range and high SNR are essential. Full article

In the context of China’s “dual-carbon” strategy, the Beijing 2022 Winter Olympics provides a critical case for examining whether carbon-neutral commitments can be translated into measurable and lasting environmental outcomes through a closed-loop governance mechanism. This study develops an integrated analytical framework linking institutional design, policy tools, monitoring–reporting–verification (MRV), and environmental legacy, and evaluates full life-cycle carbon-neutral governance and post-event environmental performance using officially verified carbon accounting materials, governmental disclosures, and publicly available statistical data from 2016–2022. We synthesize the emission structure across preparation and Games-time phases, examine key mitigation and offset portfolios, and assess multi-dimensional environmental indicators in Beijing and Zhangjiakou, including atmospheric quality, energy structure transition, ecological restoration, and low-carbon transport systems. The results suggest that an MRV-centered governance chain strengthened accounting transparency and compliance-oriented implementation, while environmental indicators in the competition zones exhibited sustained improvement over the study period. To reduce over-attribution under concurrent national clean-air policies and macro-level environmental governance trends, we benchmarked host-zone indicators against external reference statistics and interpret the observed improvements as an “acceleration effect” under bounded inference rather than a strict net causal contribution. The findings highlight the importance of hotspot-oriented asset-chain governance (transport infrastructure and venue construction), robust MRV disclosure, and quality-controlled offsets in shaping credible environmental legacies, and provide policy implications for future mega-events seeking to balance carbon neutrality with long-term regional sustainability. Full article

This study introduces a novel approach to producing carbon-negative food ingredients by integrating phycocyanin extraction from Spirulina (Arthrospira platensis) with the application of its residual biomass as a biostimulant for soil organic carbon (SOC) sequestration. A comprehensive life cycle assessment (LCA) was conducted to evaluate the environmental performance of this integrated system, encompassing geothermally powered Spirulina cultivation, phycocyanin extraction, and the use of the waste stream to enhance SOC in degraded Icelandic soils. Although the cultivation and extraction processes are associated with environmental impacts, the SOC sequestration resulting from biostimulant application more than offsets these burdens—yielding a net-carbon-negative natural food colorant under the assumptions applied in this study (−1.60 tCO₂-eq per color unit). This work highlights the potential for such ingredients to contribute meaningfully to Scope 3 emission reductions, in line with science-based targets and the GHG Protocol. Traditionally, food pigments have been overlooked in carbon accounting due to their low inclusion rates and perceived minimal contribution to overall product footprints. This study reframes natural colorants as strategic levers for climate action, offering a pathway for food manufacturers to advance decarbonization while transitioning toward more sustainable, bio-based ingredients. Full article

Understanding the structural drivers of global CO₂ emissions is essential for designing effective climate-mitigation strategies and for supporting progress toward Sustainable Development Goal 13 (SDG 13—Climate Action). This study applies the Kaya Identity-based decomposition approach to quantify how population, gross domestic product per capita, energy intensity, and emission intensity jointly shape long-term emission dynamics. Using harmonized historical datasets for the period 1990–2020, the analysis compares global trends with country-level trajectories in major emitting regions, including China, India, the United States, the European Union, and Russia. Results indicate that although energy and emission intensity have improved in several regions, these gains remain insufficient to offset the combined effects of population growth and rising economic output, leading to continued increases in global emissions. Significant asymmetries emerge across countries in terms of development stages, historical responsibility, and capacity for decarbonization, raising important considerations for climate equity. Overall, the Kaya decomposition provides a transparent diagnostic framework for identifying policy-sensitive levers, particularly energy intensity and carbon intensity, and for highlighting where mitigation efforts are most urgently needed to advance progress toward SDG 13. Full article

A promising route for removing antibiotics such as penicillin from wastewater is photocatalytic degradation under UV irradiation using TiO₂ nanoparticles. However, the microscopic mechanisms governing the initial degradation steps remain poorly understood. In particular, it is still unclear whether degradation preferentially occurs in solution or upon adsorption on the oxide surface, and which molecular sites are most vulnerable to attack in solution compared to those activated on the catalyst. In this work, we introduce a unified density functional theory approach that treats penicillin V (phenoxymethylpenicillin) consistently, both isolated in solution and adsorbed on an anatase TiO₂ nanocluster, enabling a direct comparison between solution-phase and surface-mediated degradation pathways. Within this framework, we analyze the adsorption configurations, energy-level alignment, charge-transfer pathways, UV-Vis absorption properties, local reactivity descriptors, and the initial steps leading to bond breaking. The results show that the direct photoexcitation of PenV followed by electron transfer to the oxide is less likely, due to the high energy of the pollutant’s excited states. In contrast, degradation initiated by the transfer of photogenerated holes from the catalyst to the adsorbed antibiotic appears more probable, driven by the smaller energetic offset and by the hybridization between molecular and oxide states. Overall, adsorption on the oxide surface appears to be more conducive to degradation, with the carbon atom in the β-lactam ring consistently identified as a susceptible site for attack across different environments. Full article

Global climate policy requires constant attention due to shifting interests and alliances between national negotiators. Whether represented at global or national scales, three universal features of fused climate policy conjoin the wealthy and emerging G20 economies that are historically responsible for the most greenhouse gas emissions. The former are represented by G7 Western powers—the United States, Europe, United Kingdom, Japan, and Canada—and the latter are centered on the fast-expanding ‘BRICS’ bloc: Brazil–Russia–India–China–South Africa (2010–2023), new members Egypt, Ethiopia, Indonesia, Iran, and the United Arab Emirates, and potentially also Saudi Arabia (a member invitee), along with ten new ‘partners’ designated in 2024, many of which have carbon-intensive economies. Although conflicts regularly arise—especially over emissions-related trade policy and climate financing—and although Donald Trump’s exit from United Nations climate politics profoundly disrupted the usually coherent G7 bloc, the consensual principles uniting these diverse Western and BRICS governments at multilateral climate summits include the following: (1) not cutting corporate, state, and household emissions to the extent necessary for avoiding unmanageable planetary disasters, in the process denying effective ways of leaving fossil fuels underground (by reimbursing poor countries); (2) not pricing carbon properly or acknowledging their economies’ ‘climate debt’; and (3) instead promoting carbon trading and offset mechanisms. The implications are important for alliance-formation involving climate-victimized, low-income countries and climate justice activists, alike. In sum, there is an increasingly urgent rationale to transcend ‘Global North’ and ‘Global South’ dichotomies and instead consider climate (like many other aspects of G7-BRICS relations) with a perspective open to critique of the imperial–subimperial fusions, not only oft-assumed frictions. Full article

Lignin, an abundant and renewable biopolymer, holds significant potential for asphalt modification owing to its unique aromatic structure and reactive functional groups. This review summarizes the main lignin preparation routes and key physicochemical attributes and assesses its applicability for enhancing asphalt performance. The physical incorporation of lignin strengthens the asphalt matrix, improving its viscoelastic properties and resistance to oxidative degradation. These enhancements are mainly attributed to the cross-linking effect of lignin’s polymer chains and the antioxidant capacity of its phenolic hydroxyl groups, which act as free-radical scavengers. At the mixture level, lignin-modified asphalt (LMA) exhibits improved aggregate bonding, leading to enhanced dynamic stability, fatigue resistance, and moisture resilience. Nevertheless, excessive lignin content can have a negative impact on low-temperature ductility and fatigue resistance at intermediate temperatures. This necessitates careful dosage optimization or composite modification with softeners or flexible fibers. Mechanistically, lignin disperses within the asphalt, where its polar groups adsorb onto lighter components to boost high-temperature performance, while its strong interaction with asphaltenes alleviates water-induced damage. Furthermore, life cycle assessment (LCA) studies indicate that lignin integration can substantially reduce or even offset greenhouse gas emissions through bio-based carbon storage. However, the magnitude of the benefit is highly sensitive to lignin production routes, allocation rules, and recycling scenarios. Although the laboratory research results are encouraging, there is a lack of large-scale road tests on LMA. There is also a lack of systematic research on the specific mechanism of how it interacts with asphalt components and changes the asphalt structure at the molecular level. In the future, long-term service-road engineering tests can be designed and implemented to verify the comprehensive performance of LMA under different climates and traffic grades. By using molecular dynamics simulation technology, a complex molecular model containing the four major components of asphalt and lignin can be constructed to study their interaction mechanism at the microscopic level. Full article

Monitoring spatiotemporal dynamics of aboveground carbon (AGC) storage at the tree species level is crucial for evaluating the ecological impacts of large-scale infrastructure projects and facilitating accurate ecological environmental management. However, existing studies heavily rely on interannual coarse-spatial-resolution forest-type products, leading to significant uncertainties in carbon estimation, particularly in fragmented linear engineering zones. This study integrated Sentinel-1/2 data with a random forest (RF) model to map tree species distribution (overall accuracy = 85.18%; Kappa = 0.8319) and AGC estimation (R² = 0.7057; RMSE = 13.35 Mg ha⁻¹) at a 10 m resolution in the Pinglu Canal Basin from 2019 to 2024. The results revealed a total AGC decline of 16.88% across the watershed. Spatially, the Environmental Impact Area (EIA) functioned as the primary disturbance core (experiencing a 28.91% loss), while the Ecological Buffer Area (EBA) acted as a regional carbon stabilizer. At the species level, while Eucalyptus grandis accounted for the majority of carbon depletion, Pinus massoniana exhibited a resilience-driven rebound in the mid-construction phase. Meanwhile, Litchi chinensis and other native species demonstrated steady gains. Cumulatively, these species-specific carbon gains associated with natural growth and restoration initiatives effectively offset 34.45% of the carbon loss. These findings provide quantitative evidence supporting the potential of green engineering to mitigate the ecological footprint of infrastructure development. This study offers a robust monitoring tool for low-carbon infrastructure and directly supports the United Nations Sustainable Development Goal 15 (SDG 15) related to forest conservation and ecological restoration. Full article

Global warming (GW) contributions from feedbacks and feedback loops are projected to rise from ≈54% (loops: 29%) in 2024 to ≈71% (loops: 50%) under faltering RCP pathways without Solar Geoengineering (SG) by about 2100. A critical threshold, RCP_Critical, defined as the point at which feedback loops account for more than half of GW, is projected to occur between 2075 and 2125. Beyond this point, reversing warming becomes severely constrained, and climate tipping points become more likely. From these trends, an average mitigation difficulty and cost increase rate (MDCR) of ≈1.33–1.5% per year is estimated. By 2100, absent mitigation, the effort required to offset global warming would roughly double relative to today, approaching an unsustainable mitigation critical threshold. Current feedback levels may already be driving nonlinear warming behavior. These diagnostic estimates align with three key indicators: a minimum-feedback baseline from 1870, an equilibrium climate sensitivity (ECS) range of 3.1 °C–4.3 °C (potentially reached by ≈2082), and consistency with IPCC AR6 confidence bounds. In response, this study proposes Annual Solar Geoengineering-PLUS pathways (ASG+Ps) as supplemental measures. These include Earth Brightening, targeted Arctic Stratospheric Aerosol Injection (SAI), and feasible L1 Space Sunshade systems designed to reduce feedback amplification and extend mitigation timelines. The “PLUS” component refers to the use of increased mitigation levels with a focus on high-amplification regions, particularly the Arctic and the tropics, to help reverse local feedbacks and promote negative feedback loops. These moderate ASG+P pathways directly address AR6 concerns while avoiding many governance challenges of full-scale SG. ASG+Ps are less controversial and provide ≈14× stronger cooling potential per Wm⁻² than Carbon Dioxide Removal (CDR), while allowing variable regional targeting. Meanwhile, RCP2.6 has already been missed, placing RCP4.5 and RCP6 at risk. In 2024, atmospheric CO₂ rose by ≈23 Gt (≈3 ppm), while forest tree losses exceeded afforestation gains by 2×, yielding a 2 GtCO₂ sink loss, further diminishing CDR’s effectiveness. Declines in planetary albedo since 1998 continue to amplify warming. Urbanization accounts for roughly 13% of total surface GW, affecting 60% of the population, underscoring the mitigation potential of urban Earth Brightening. New results here also show major Space Sunshading area reductions, at ≈32× less than prior flawed estimates (detailed here) and ≈1600× less under the ASG+P method, substantially improving feasibility and the importance of space agencies’ needed mitigation role. A coordinated global ASG+P strategy, supported by IPCC working groups and space agencies like NASA/SpaceX, are needed to provide a critical supplemental pathway for climate stabilization. Given the shrinking intervention window, rising MDCR, and the escalating risks to civilization, prioritizing timely work in this area is essential; the investment is minor compared to the trillions in climate financial damages that could be avoided. Full article