Search Results (61)

Landfills serve as a primary disposal method for municipal solid waste in China, with over 20,000 operational sites nationwide; however, long-term operations risk leachate leakage and groundwater contamination. Amid intensifying climate change and human activities, understanding contaminant evolution mechanisms in landfills has become critically urgent. Focusing on a representative plain-based landfill in North China, this study integrated field investigations and groundwater monitoring to establish a monthly coupled groundwater flow–solute transport model (using MODFLOW and MT3DMS codes) based on site-specific hydrogeological boundaries and multi-year monitoring data, analyzing spatiotemporal plume evolution under the coupled impacts of precipitation variability (climate change) and intensive groundwater extraction (human activities), spanning the historical period (2021–2024) and future projections (2025–2040). Historical simulations demonstrated robust model performance with satisfactory calibration against observed water levels and chloride concentrations, revealing that the current contamination plume exhibits a distinct distribution beneath the site. Future projections indicate nonlinear concentration increases: in the plume core zone, concentrations rise with precipitation, whereas at the advancing front, concentrations escalate with extraction intensity. Spatially, high-risk zones (>200 mg/L) emerge earlier under wetter conditions—under the baseline scenario (S0), such zones form by 2033 and exceed site boundaries by 2037. Plume expansion scales positively with extraction intensity, reaching its maximum advancement and coverage under the high-extraction scenario. These findings demonstrate dual drivers—precipitation accelerates contaminant accumulation through enhanced leaching, while groundwater extraction promotes plume expansion via heightened hydraulic gradients. This work elucidates coupled climate–human activity impacts on landfill contamination mechanisms, proposing a transferable numerical modeling framework that provides a quantitative scientific basis for post-closure supervision, risk assessment, and regional groundwater protection strategies, thereby aligning with China’s Standard for Pollution Control on the Landfill Site of Municipal Solid Waste and the Zero-Waste City initiative. Full article

In recent years, China has made strong national commitments to waste reduction and circular economy, including the implementation of mandatory municipal solid waste separation policies and the rollout of zero-waste city initiatives. These efforts represent a strategic shift toward systemic environmental governance. However, the outbreak of the COVID-19 pandemic in early 2020—and the subsequent implementation of the country’s stringent zero-COVID policy—led to an abrupt disruption of these programs. Under this policy, strict lockdowns, quarantine of both confirmed and suspected cases, and city-wide containment became top priorities, sidelining environmental initiatives such as waste separation and sustainable waste infrastructure development. This study investigates how Chinese residents’ motivations for waste separation evolved across three key phases: pre-pandemic, during the zero-COVID enforcement period, and post-pandemic recovery. Grounded in the Theory of Planned Behavior and pro-environmental behavior theory, we developed an extended model incorporating pandemic-related social, psychological, and policy variables. Based on 526 valid questionnaire responses collected in late 2023 in Shanghai, we conducted structural equation modeling and repeated-measures analysis. Findings reveal a significant shift from externally driven compliance—reliant on governmental enforcement and service provision—to internally motivated behavior based on environmental values and personal efficacy. This transition was most evident after the pandemic, suggesting the potential for sustained pro-environmental habits despite weakened policy enforcement. Our findings underscore the importance of strengthening internal drivers in environmental governance, especially under conditions where policy continuity is vulnerable to systemic shocks such as public health emergencies. Full article

This study approaches the “Zero-Waste City (ZWC)” initiative as a quasi-natural experiment. Utilizing panel data from 273 prefecture-level cities in China from 2013 to 2023, it employs a multi-period difference-in-differences model to systematically assess the initiative’s synergistic impacts on pollution and carbon emission (CE) reductions. The findings indicate that the initiative has notably lowered both urban pollution and CEs. These results remain robust following a series of stability tests, which include dynamic effect analyses, placebo tests, and propensity score matching. Mechanism analysis suggests that the policy primarily achieves its pollution and carbon reduction goals through four pathways: green technological innovation, public participation and oversight, source control, and end-of-pipe treatment. Heterogeneity analysis further demonstrates that the policy’s effects are more pronounced in resource-based cities, regions with advanced digitalization, and areas with stringent environmental regulations. Additionally, “ZWC” initiatives notably enhance synergies between pollution reduction and carbon mitigation, especially in controlling pollutants closely associated with energy consumption, such as sulfur dioxide and particulate matter. This research provides empirical evidence and policy recommendations for promoting “ZWC” development and optimizing environmental governance systems. Full article

Policy misalignment is a key factor affecting the implementation of solid waste management policies and resolving such a misalignment is critical to advancing the solid waste disposal capacity (SWDC) and supporting the goal of a “zero-waste city”. This policy misalignment indicator provides a measurable tool to track progress toward Sustainable Cities and Communities. This study used panel data from 281 cities at the prefecture level and above from 2018 to 2022. The study involved constructing an original database of central and provincial policy documents on urban waste governance and transforming the policy documents into an indicator to capture the degree of policy misalignment, which serves as the key explanatory variable in a fixed-effects model. The study further examined how fiscal decentralization, the digital economy, and regional and administrative characteristics influence cities’ responses to policy misalignments. These factors serve a vital function in moderating the effects of misalignment and explaining heterogeneity across cities. The empirical results show that a vertical policy misalignment significantly reduced the solid waste disposal capacity, while fiscal decentralization and digital economy development mitigated its negative effects. The adverse impacts were particularly pronounced in non-key cities, eastern regions, and cities with low government attention, highlighting the role of local capacity and administrative focus in mediating cross-level policy impacts. The heterogeneous effects observed across city types further offer targeted insights for designing sustainability-oriented waste management policies, enabling regions to tailor interventions based on their administrative capacity and development context. Full article

In recent years, European cities have implemented numerous initiatives to reduce the use of resources and improve the resilience of climate change by promoting shifts toward the circular economy (CE). This comparative case study investigated the results of the applications of the CE model in the built environment from two different national approaches and perspectives of strategic planning in capitals that represent the “old” (Copenhagen) and “new” (Ljubljana) European Union (EU) member states. This paper introduces the original methodology to assess the implementation of the strategic approaches in the adaptation of the CE in architecture and urban design using a set of 10 selecting indicators. Although both cities have ambitious strategic goals and are undertaking actions aimed at shifting to the CE, they are driven by different motivations (climate crisis vs. urban revitalization and zero waste policy) and exhibit different implementation patterns (top-down systemic/institutional vs. gradual/sectoral). The results highlight the key role of a comprehensive approach to CE implementation, particularly the development of institutional frameworks and dedicated infrastructure and digital tools for transition management, the involvement of external stakeholders in the circular vision, wide-range educational activities, and the promotion of CE initiatives. However, limitations resulting from the lack of a comprehensive and standardized measurement framework pose a challenge to effectively accelerate progress in the shift toward a CE in the built environment. The main contributions of this study are: (1) to identify and verify the methods and strategies undertaken by European cities for the adaptation of a CE in the built environment and (2) demonstrate the different dimensions, levels, and the most relevant factors in the strategic management of the processes of transformation toward the CE. In addition, recommendations for future implementations based on CE systems are indicated. Full article

The exponential increase in global solid waste generation poses significant environmental, economic, and social challenges, particularly in rapidly urbanizing regions. Traditional waste management methods that focus on handling and disposal have proven unsustainable because of their negative impacts on air, soil, and water quality, and their contribution to greenhouse gas emissions. In response, the concept of zero-waste cities, rooted in circular economy principles, has gained increasing attention in recent years. This study proposes a comprehensive and integrated waste management system designed to optimize resource recovery across four distinct waste streams: household, healthcare, green/organic, and inert. The system integrates four specialized facilities: a Secondary Sorting Facility, Energy Recovery Facility, Composting Facility, and Inert Processing Facility, coordinated through a central Primary Sorting Hub. By enabling interconnectivity between these processing units, the system facilitates material cascading, maximizes the reuse and recycling of secondary raw materials, and supports energy recovery and circular nutrient flow. The anticipated benefits include enhanced operational efficiency, reduced environmental degradation, and generation of multiple revenue streams. However, the implementation of such a system faces challenges related to high capital investment, technological complexity, regulatory fragmentation, and low public acceptance. Overcoming these limitations will require strategic planning, stakeholder engagement, and adaptive governance. Full article

This study combines convolutional neural network (CNN) recognition technology, Greenwich engineering software, and statistical yearbook methods to evaluate rural solar, wind, and biomass energy resources in pilot cities in China, respectively. The CNN method enables the rapid identification of the available roof area, and Greenwich software provides wind resource simulation with local terrain adaptability. The results show that the capacity of photovoltaic power generation reaches approximately 15.63 GW, the potential of wind power is 458.3 MW, and the equivalent of agricultural waste is 433,900 tons of standard coal. The city is rich in wind, solar, and biomass resources. By optimizing the hybrid power generation system through genetic algorithms, wind energy, solar energy, biomass energy, and coal power are combined to balance the annual electricity demand in rural areas. The energy trends under different demand growth rates were predicted through the LEAP model, revealing that in the clean coal scenario of carbon capture (WSBC-CCS), clean coal power and renewable energy will dominate by 2030. Carbon dioxide emissions will peak in 2024 and return to the 2020 level between 2028 and 2029. Under the scenario of pure renewable energy (H_WSB), SO₂/NO_x will be reduced by 23–25%, and carbon dioxide emissions will approach zero. This study evaluates the renewable energy potential, power system capacity optimization, and carbon emission characteristics of pilot cities at a macro scale. Future work should further analyze the impact mechanisms of data sensitivity on these assessment results. Full article

Systematic assessment of heavy metal contamination in agricultural soils is critical for addressing ecological and public health risks in industrial-intensive cities like Lanzhou, with direct implications for achieving UN Sustainable Development Goals (SDGs) 2 (Zero Hunger), 15 (Life on Land), and 3 (Good Health). The present study evaluates farmland soils around six industrial sectors: waste disposal (WDZ), pharmaceutical manufacturing (PMZ), chemical manufacturing (CMZ), petrochemical industry (PIZ), metal smelting (MSZ), mining (MZ) and one sewage-irrigated zone (SIZ) using geo-accumulation index, Nemerow composite pollution index, potential ecological risk index, and health risk models. The following are the major findings: (1) SIZ and PMZ emerged as primary contamination clusters, with Hg (I_geo = 1.89) and Cd (I_geo = 0.61) showing marked accumulation. Chronic wastewater irrigation caused severe Hg contamination (0.97 mg·kg⁻¹) in SIZ, where 100% of the samples reached strong polluted levels according to the Nemerow composite pollution index; (2) Hg and Cd dominated the ecological risks, with 41.32% of the samples exhibiting critical Hg risks (100% in PMZ and SIZ) and 32.63% showing strong Cd risks; and (3) oral ingestion constituted the dominant exposure pathway. Children faced carcinogenic risks (CR = 1.33 × 10⁻⁴) exceeding safety thresholds, while adult risks remained acceptable. Notably, high Hg and Cd levels did not translate to proportionally higher health risks due to differential toxicological parameters. The study recommends prioritizing Hg and Cd control in PMZ and SIZ, with targeted exposure prevention measures for children. Full article

To scientifically assess the energy-saving effects of China’s zero-waste city pilot (ZWCP) policies and provide empirical evidence and policy insights for advancing pilot policies and accelerating energy conservation and emission reduction goals, this study selected 274 cities in China from 2010 to 2022 as the research sample, employing a double machine learning model to empirically analyze the impact of pilot policies on urban energy consumption intensity. The research results demonstrate that the ZWCP policies significantly reduced energy consumption intensity in pilot areas. Channel analysis reveals that this policy exerted a restraining effect on energy consumption intensity through industrial structure upgrading, green technology innovation, and enhanced environmental awareness. Heterogeneity analysis shows that policy effects were more pronounced in non-urban agglomeration regions, inland areas, and small-to-medium-sized cities. This study provides crucial decision-making references for the promotion and implementation of ZWCP policies during the “14th Five-Year Plan” period. Full article

This paper shows a case study on a novel community-based sustainability planning framework that balances environmental, social, cultural dimensions for a high-density urban setting. The case study presents a community-driven “Four-Zero” sustainability model—zero energy, zero water, zero food, and zero waste—as a foundation for environmental sustainability practices implemented in a high-density estate in Hong Kong, alongside community-led ecological and heritage initiatives that reinforce place-based resilience. Through integrated activities, such as community farming, aquaponics, organic waste composting, biodiversity monitoring, and heritage mapping, the residents co-produced knowledge and activated novel bottom–up planning schemes and fostered social cohesion while advancing environmental objectives. Notably, the discovery of rare species and historic Dairy Farm remnants catalyzed a community-led planning proposal for an eco-heritage park that stimulated policy dialogues on conservation. These collective efforts illustrate how circular resource systems and cultural and ecological conservation can be balanced with urban development needs in compact, high-density communities. This case offers policy insights for rethinking urban sustainability planning in dense city contexts, contributing to global discourses on urban political ecology by examining socio–nature entanglements in contested urban spaces, to environmental justice by foregrounding community agency in shaping ecological futures, and to commoning practices through shared stewardship of urban resources. Full article

Solid waste governance actions are important to achieve sustainable urban development. This study uses the “zero-waste city” pilot policy as a natural experiment to evaluate the impact of solid waste governance actions on corporate environmental, social, and governance (ESG) performance. The research shows that solid waste governance actions improve corporate ESG performance by enhancing government environmental concerns, public environmental concerns, and corporate green innovation. The analysis of spillover effects indicates that solid waste governance exerts positive spatial spillover effects. Heterogeneity tests reveal that the positive effect of solid waste governance actions on corporate ESG performance is more pronounced in enterprises characterized by higher-quality information disclosure and stronger internal governance, industries with greater solid waste output and more advanced technology, regions with a closer government–market relationship, and in central–eastern regions. These findings contribute to understanding the micro-level effects of solid waste governance actions and the determinants of corporate ESG performance, providing valuable insights for other developing countries to govern solid waste and improve corporate ESG performance. Full article

Efficient waste management is instrumental in both reducing waste generation and mitigating CO₂ emissions. The Zero-waste City Pilot (ZWCP) policy, a location-oriented waste governance initiative, aims to minimize waste production, enhance waste management efficiency, and improve resource utilization. Therefore, does the ZWCP policy achieve the dual environmental effect of pollution reduction and carbon mitigation? Based on panel data from 158 cities in China from 2011 to 2021, this paper employed a difference-in-differences (DID) model to empirically assess the impact of the ZWCP policy on solid waste and CO₂ emissions. The results indicate that: (1) The ZWCP policy effectively reduced both solid waste and CO₂ emissions, and the estimation results are robust as shown by robustness testing. (2) The policy achieved pollution reduction and carbon mitigation through two transmission mechanisms: stimulating green technological innovation and strengthening environmental regulation. (3) Heterogeneity analysis revealed that the policy’s effects on pollution reduction and carbon mitigation are more pronounced in central regions, non-resource-based cities, and large cities. (4) The ZWCP policy demonstrated no discernible enterprise exit effect, indicating its success in balancing environmental protection with economic growth, thereby providing a strong rationale for its extension to additional pilot regions. (5) The spatial spillover effect analysis revealed no significant spatial spillover of the ZWCP policy’s dual environmental effects. This may stem from the policy’s urban-centric implementation, uneven resource allocation and weak cross-regional collaboration mechanisms—factors that highlight the necessity for stronger cross-regional governance in waste management strategies. The study’s conclusions carry important policy implications for advancing China’s ecological civilization goals while provide valuable insights for other developing countries seeking to design effective zero-waste strategies. Full article

This research aims to identify appropriate strategies for reducing CO₂ emissions under the carbon neutrality framework within Smart City Thailand. The Path Solow model based on vector moving average–GARCH in mean with environmental pollution (PS–VMA–GARCHM–EnPoll model) has been developed, and it is a highly suitable tool for environmental protection. This model can also be applied to other sectors and stands out from previous models by effectively prioritizing key factors for long-term strategic planning in a concrete and efficient manner. Additionally, the model illustrates the direction of causal relationships, both positive and negative, which is highly beneficial for more concrete policy formulation. This allows the government to determine which factors should be reduced or receive less support and which factors should be promoted for greater growth compared to the past. The findings suggest two strategic approaches to reducing CO₂ emissions: (1) New-scenario policy based on high-sensitivity indicators—By selecting indicators with a sensitivity analysis value above 90%, including clean technology, renewable energy rate, biomass energy, electric vehicles, and green material rate, CO₂ emissions can be reduced by 43.06%, resulting in a total CO₂ gas emission of 398.01 Mt CO₂ Eq. by 2050, which is below Thailand’s carrying capacity threshold of 450.07 Mt CO₂ Eq.; and (2) Expanded-scenario policy using all indicators with sensitivity above 80%—By incorporating additional indicators, such as waste biomass, gasohol use rate, fatty acid methyl ester rate, and solar cell rate, along with those in the first scenario, CO₂ emissions can be reduced by 60.65%, leading to a projected CO₂ gas emission of 275.90 Mt CO₂ Eq. by 2050, which aligns with Thailand’s national strategy goal of reducing CO₂ gas emissions by at least 40% by 2050 and sets the country on the right path toward achieving net-zero greenhouse gas emissions by 2065. Thus, implementing the PS–VMA–GARCHM–EnPoll model can effectively contribute to the long-term national strategy for greenhouse gas reduction, ensuring sustainable environmental management for the future. Full article

To achieve the goal of building zero-waste cities, managing greenhouse gas (GHG) emissions generated from municipal solid waste (MSW) treatment is a critical step toward carbon neutrality. Waste produced by consumption activities constitutes an essential component of MSW management. Using the Super Slacks-Based Measure Data Envelopment Analysis (SSBM-DEA) model and the Spatial Durbin Model (SDM), this study investigates the spatial impacts of consumption upgrading (CU) on municipal waste management across 30 provinces in China, with a particular focus on GHGs as undesirable outputs. In this study, we construct a framework from the dimensions of consumption level, consumption structure, and green consumption. Additionally, other socioeconomic factors influencing waste management are explored. The results indicate a convergence trend in the uneven distribution of consumption upgrading, with the gaps between regions gradually narrowing. Consumption upgrading significantly enhances the eco-efficiency of local waste management and exhibits notable spatial spillover effects, positively influencing the eco-efficiency of neighboring regions. Furthermore, the promotion effect of consumption upgrading on the central and western regions, compared with the eastern region, is more pronounced. This indicates that the technological catch-up resulting from consumption upgrading, supported by policies, can further enhance the eco-efficiency of MSW. This study also provides insights for other regions transitioning from scale expansion to high-quality development in waste management. Full article

Waste is a complex challenge that requires collaboration between multiple stakeholders to achieve a circular economy. In this context, there is a growing demand for digital solutions that integrate physical and digital infrastructure to create digital waste governance systems. Analog management, without accurate data, is becoming increasingly unfeasible in light of the UN Sustainable Development Goals. Tools such as online geographic information systems (WebGIS) allow the collection and integration of large volumes of physical and human data and the establishment of a digital governance structure that brings together different technologies, tools and methods in the same environment. This article aims to present the State of the Art on the topics of zero-waste cities, WebGIS, and disruptive innovation. The article starts from the hypothesis that only a process of disruptive and systemic innovation in the value chain and urban solid waste management (MSWMS), supported by the principle of zero-waste cities, circular economy and webGIS, can effectively help to solve this problem. The research uses an exploratory literature review on the concepts of zero-waste cities, systemic innovation and webGIS applied to waste management, linking them to the theoretical framework of sustainability as a science and to Brazilian public policies, such as the National Solid Waste Policy (Law 12.305/2010), the National Circular Economy Policy (Law 1.874/2022) and the National Digital Government Strategy of Brazil 2024–2027 (ENGD). As a result, scientific publications on zero-waste cities increased from 2018 to 2023 and several countries have adopted zero-waste guidelines in waste management policies. WebGIS, remote sensing, geoprocessing and different technologies are increasingly being incorporated into waste management, generating significant impacts on the diversion of resources from landfills, mitigating climate change, and generating and/or adding value to the useful life of waste and garbage resources, in addition to the optimization and efficiency of collection operators and citizen engagement in public policies. Disruptive innovation has proven to be a concrete process to enable the transition from obsolete sociotechnical systems (such as the linear economy), where sustainable finance and environmental entities play a fundamental role in orchestrating and coordinating the convergence of private, public and civil society actors towards this new sustainable development paradigm. The case study proved to be fruitful in proposing and encouraging the adoption of such methods and principles in municipal waste management, allowing us to outline a first conception of a digital government structure and digitalization of public services for zero-waste cities, as well as pointing out the difficulties of implementing and transforming these systems. This digital governance structure demonstrates the possibility of being replicable and scalable to other cities around the world, which can materialize an important tool for the implementation, articulation and development of a long-term sustainable development paradigm, based on the vision of the circular economy and zero-waste cities. Full article