- Kinh nghiệm so sánh xuyên lục địa về giám sát nước thải và tầm nhìn cho thế kỷ 21.

- Nghiên cứu tác động tổng hợp giảm lượng carbon của chính sách mua bán phát thải sulfur dioxide.

- Tổng lượng carbon mất đi trong đất hàng thập kỷ ở vùng nội địa phía bắc cao nguyên Tây Tạng.

- Đánh giá có hệ thống: Vai trò của các công nghệ thu giữ và chuyển đổi carbon mới nổi trong quá trình chuyển đổi năng lượng sang hydro sạch.

- Sức mạnh tổng hợp toàn cầu của phát thải carbon và ô nhiễm giữa các quốc gia có mức thu nhập và giai đoạn phát triển khác nhau.

- Chất thải nhựa đóng gói từ lĩnh vực thương mại điện tử: Kịch bản của Ấn Độ và giải pháp sản xuất sạch hơn đa diện hướng tới giảm thiểu chất thải.

- Hệ thống sản xuất hydro với lượng khí thải carbon dioxide gần như bằng 0 nhờ việc sử dụng bổ sung khí tự nhiên và điện.

- Một đánh giá khoa học tiên tiến về việc sử dụng số lượng bản sao DNA ty thể làm dấu ấn sinh học khi tiếp xúc với môi trường. 

- Xem xét tác động của sự không chắc chắn về chính sách kinh tế đối với tính bền vững của môi trường: Cái nhìn sâu sắc từ các quốc gia Bắc Âu.

- Năng lượng tái tạo, bất bình đẳng và suy thoái môi trườngCải thiện việc định lượng nồng độ hạt mịn (PM2.5) ở Malaysia bằng cách sử dụng các mô hình đơn giản và hiệu quả về mặt tính toán.

- Khám phá mối liên kết giữa hình thái đô thị, tính di động và khí thải với OLYMPUS: Phân tích so sánh ở hai vùng của Pháp.

- Tích hợp tối ưu hóa năng lượng mặt trời và tái hóa khí tự nhiên hóa lỏng để phát triển đô thị bền vững: Mô hình động, tối ưu hóa dựa trên dữ liệu và nghiên cứu điển hình.

- La-Nina ba lần, hoàn lưu không chính thống và sự quay vòng bất thường trong chất lượng không khí của Ấn Độ.

- Sự phát triển không gian-thời gian và cơ chế thúc đẩy khả năng phục hồi đô thị ở các thành phố thuộc lưu vực sông Hoàng Hà.

- Các nguồn góp phần gây ra rủi ro sức khỏe liên quan đến hydrocacbon thơm đa vòng gắn PM2.5 trong mùa ấm và mùa lạnh ở một khu vực đô thị ở Đông Á.

- Dự báo thuộc tính xu hướng về xu hướng PM2.5 hàng giờ tại 15 thành phố ở miền Trung nước Anh áp dụng lựa chọn tính năng học máy được tối ưu hóa Tiến tới một số mục tiêu phát triển bền vững ở các thành phố đang thu hẹp dân số của Trung Quốc.

- Đánh giá hiệu quả của các biện pháp phát triển có tác động thấp đến nguy cơ lũ lụt đô thị.

- Đặc tính của vi hạt nhựa trong không khí ngoài trời và trong nhà ở Ranchi, Jharkhand, Ấn Độ: Những hiểu biết đầu tiên về khu vực.

- Ảnh hưởng sức khỏe của việc tiếp xúc với các hạt vật chất trong môi trường đô thị: Một nghiên cứu thống kê không gian trên phụ nữ mang thai trong tam cá nguyệt thứ 3.

- Ảnh hưởng của kim loại nặng và á kim đến quá trình phân hủy sinh học các chất ô nhiễm hữu cơ.

- Đánh giá cường độ, biến dạng và tác động môi trường của đất phủ ổn định mỏ xi măng.

- Hiểu biết cơ học về các hạt nano xeri tổng hợp màu xanh lá cây cho quá trình phân hủy quang xúc tác của thuốc nhuộm và kháng sinh từ môi trường nước và hiệu quả kháng khuẩn: Đánh giá.

- Khai thác, mô tả đặc tính hóa lý và cấu trúc của sợi lá cỏ cọ để sản xuất bền vững và sạch hơn trong ngành dệt may và các ứng dụng xenlulo tương tự.

- Tài chính xanh làm thay đổi tăng trưởng xanh của các nước phát triển: Tác động trung gian của đổi mới công nghệ sạch và hiệu ứng ngưỡng của thuế môi trường.

- Sự đóng góp của vi nhựa theo thời gian của một khu đô thị và công nghiệp lớn vào trầm tích sông.

- Chất thải công nghiệp giàu sắt tăng cường vật liệu tổng hợp chức năng che chắn bức xạ carbon thấp.

- Đánh giá chất lượng đất dựa trên máy học để tăng cường giám sát môi trường trong các hệ sinh thái bị ảnh hưởng bởi hoạt động khai thác quặng sắt.

- Chất hấp phụ để khử nhiễm nước: Một giải pháp tái chế thay thế cho tiền chất sợi và chất thải sợi dệt.

ENVIRONMENTAL MANAGEMENT / QUẢN LÝ MÔI TRƯỜNG 

Science of The Total Environment, Volume 919, 1 April 2024, 170842

Abstract

The COVID-19 pandemic has brought the epidemiological value of monitoring wastewater into sharp focus. The challenges of implementing and optimising wastewater monitoring vary significantly from one region to another, often due to the array of different wastewater systems around the globe, as well as the availability of resources to undertake the required analyses (e.g. laboratory infrastructure and expertise). Here we reflect on the local and shared challenges of implementing a SARS-CoV-2 monitoring programme in two geographically and socio-economically distinct regions, São Paulo state (Brazil) and Wales (UK), focusing on design, laboratory methods and data analysis, and identifying potential guiding principles for wastewater surveillance fit for the 21st century. Our results highlight the historical nature of region-specific challenges to the implementation of wastewater surveillance, including previous experience of using wastewater surveillance, stakeholders involved, and nature of wastewater infrastructure. Building on those challenges, we then highlight what an ideal programme would look like if restrictions such as resource were not a constraint. Finally, we demonstrate the value of bringing multidisciplinary skills and international networks together for effective wastewater surveillance.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141483

Abstract

Since General Secretary Xi Jinping pledged the "30·60” targets to the world, the importance of pollution reduction and carbon reduction has become increasingly prominent. The previous focus on the pollution reduction effects of emission trading systems, while overlooking their carbon reduction impacts, as well as the limitations of research methods and scope, is no longer suitable for the needs of the new era. Therefore, this paper constructs a CGE model to study the synergistic effects, simulating the synergistic emission reduction effects of sulfur dioxide emission trading policies, and comes to the following conclusions: After the implementation of the sulfur dioxide emission trading mechanism, under different sulfur price scenarios, the synergistic reduction amounts of SO2 and CO2 vary greatly. As the sulfur price increases, the reduction amount becomes larger. In the five sulfur price scenarios set in this paper, the maximum reduction of SO2 can reach about 111,400 tons, and the maximum for CO2 is about 399 million tons. The CO2 reduction rate is approximately 1.0767 times that of SO2. This indicates that the sulfur dioxide emission trading policy is a very effective path for synergistic pollution and carbon reduction, with good reduction effects. In addition, sulfur dioxide emission trading will reduce the consumption of fossil energy, decrease industry output, raise product prices, cause GDP loss, and lead to reduced social welfare to varying degrees.

Science of The Total Environment, Volume 920, 10 April 2024, 170682

Abstract

A two-year (March 2021 to February 2023) continuous atmospheric CO2 and a one-year regular atmospheric 14CO2 measurement records were measured at the northern foot of the Qinling Mountains in Xi'an, China, aiming to study the temporal characteristics of atmospheric CO2 and the contributions from the sources of fossil fuel CO2 (CO2ff) and biological CO2 (CO2bio) fluxes. The two-year mean CO2 mole fraction was 442.2 ± 16.3 ppm, with a yearly increase of 4.7 ppm (i.e., 1.1 %) during the two-year observations. Seasonal CO2 mole fractions were the highest in winter (452.1 ± 17.7 ppm) and the lowest in summer (433.5 ± 13.3 ppm), with the monthly CO2 levels peaking in January and troughing in June. Diurnal CO2 levels peaked at dawn (05:00–07:00) in spring, summer and autumn, and at 10:00 in winter. 14C analysis revealed that the excess CO2 (CO2ex, atmospheric CO2 minus background CO2) at this site was mainly from CO2ff emissions (67.0 ± 26.8 %), and CO2ff mole fractions were the highest in winter (20.6 ± 17.7 ppm). Local CO enhancement above the background mole fraction (ΔCO) was significantly (r = 0.74, p < 0.05) positively correlated with CO2ff in a one-year measurement, and ΔCO:CO2ff showed a ratio of 23 ± 6 ppb/ppm during summer and winter sampling days, much lower than previous measurements and suggesting an improvement in combustion efficiency over the last decade. CO2bio mole fractions also peaked in winter (14.2 ± 9.6 ppm), apparently due to biomass combustion and the lower and more stable wintertime atmospheric boundary layer. The negative CO2bio values in summer indicated that terrestrial vegetation of the Qinling Mountains had the potential to uptake atmospheric CO2 during the corresponding sampling days. This site is most sensitive to local emissions from Xi'an and to short distance transportation from the southern Qinling Mountains through the valleys.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141589

Abstract

The coordination of economic development and ecological conservation has emerged as a global trend for sustainable development. This paper utilizes the "Broadband China" policy as a quasi-natural experiment, employing panel data from 279 prefecture-level cities spanning from 2006 to 2019. By constructing a spatial difference-in-differences (SDID) model, it examines the impact of digital infrastructure (DI) on industrial ecology (IE). The study finds that DI enhances both local and neighboring IE, with a spatial attenuation boundary of 600 km for IE impacts on neighboring cities. DI primarily facilitates the transformation of IE by promoting green technology innovation and expediting factor mobility. Heterogeneity analysis conducted using a spatial difference-in-difference-in-differences (SDDD) model reveals that DI has a greater impact on IE in resource-based cities, highly marketized regions, small-scale cities, and eastern regions. This research provides a novel perspective for exploring the transformation of IE theoretically and offers practical insights for leveraging digitization to promote IE.

Science of The Total Environment, Volume 922, 20 April 2024, 171190

Abstract

As the largest and highest plateau in the world, ecosystems on the Tibetan Plateau (TP) imply fundamental ecological significance to the globe. Among the variety, alpine grassland ecosystem on the TP forms a critical part of the global ecosystem and its soil carbon accounts over nine tenths of ecosystem carbon. Revealing soil carbon dynamics and the underlying driving forces is vital for clarifying ecosystem carbon sequestration capacity on the TP. By selecting northern TP, the core region of the TP, this study investigates spatiotemporal dynamics of soil total carbon and the driving forces based on two phases of soil sampling data from the 2010s and the 2020s. The research findings show that soil total carbon density (STCD) in total-surface (0–30 cm) in the 2010s (8.85 ± 3.08 kg C m−2) significantly decreased to the 2020s (7.15 ± 2.90 kg C m−2), with a decreasing rate (ΔSTCD) of −0.17 ± 0.39 kg C m−2 yr−1. Moreover, in both periods, STCD exhibited a gradual increase with soil depth deepening, while ΔSTCD loss was more apparent in top-surface and mid-surface than in sub-surface. Spatially, ΔSTCD loss in alpine desert grassland was −0.41 ± 0.48 kg C m−2 yr−1, which is significantly higher than that in alpine grassland (−0.11 ± 0.31 kg C m−2 yr−1) or alpine meadow (−0.04 ± 0.28 kg C m−2 yr−1). The STCD in 2010s explained >30 % of variances in ΔSTCD among the set of covariates. Moreover, rising temperature aggravates ΔSTCD loss in alpine desert grassland, while enhanced precipitation alleviates ΔSTCD loss in alpine meadow. This study sheds light on the influences of climate and background carbon on soil total carbon loss, which can be benchmark for predicting carbon dynamics under future climate change scenarios.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141506

Abstract

The exploitation of fossil fuels in various sectors, such as power and heat generation, and the transportation sector has been the primary source of greenhouse gas (GHG) emissions, which are the main contributors to global warming. Qatar's oil and gas sector notably contributes to CO2 emissions, accounting for half of the total emissions. Globally, it is essential to transition into cleaner fossil fuel production to achieve carbon neutrality on a global scale. In this paper, we focus on clean hydrogen, considering carbon capture to make hydrogen a viable low carbon energy alternative for the transition to clean energy. This paper systematically reviews emerging technologies in carbon capture and conversion (CCC). First, the road map stated by the Intergovernmental Panel on Climate Change (IPCC) to reach carbon neutrality is discussed along with pathways to decarbonize the energy sector in Qatar. Next, emerging CO2 removal technologies, including physical absorption using ionic liquids, chemical looping, and cryogenics, are explored and analyzed regarding their advancement and limitations, CO2 purity, scalability, and prospects. The advantages, limitations, and efficiency of the CO2 conversion technology to value-added products are grouped into chemical (plasma catalysis, electrochemical, and photochemical) and biological (photosynthetic and non-photosynthetic). The paper concludes by analyzing pathways to decarbonize the energy sector in Qatar via coupling CCC technologies for low-carbon hydrogen, highlighting the challenges and research gaps.

Science of The Total Environment, Volume 922, 20 April 2024, 171322

Abstract

The world was drift away on the sustainable development goals (SDGs), whatever global countries claimed fighting for. It's thus essential to illustrate the status of development and environmental quality simultaneously. Resource consumption and energy consumption as the basic needs in supporting human societal development, are commonly used, because they come from the same source and are most directly observed in the open air. We thus examined nexus of carbon and pollution emissions, which also directly indicate residents' livelihood and lifestyle. The possibility of the nexus shifts among income levels with population stack analysis was further investigated. Our findings indicate that the diverse nexus is strongly correlated with development levels, with urban areas being the primary contributor to high carbon and/or pollution emissions despite occupying only 0.5% of global territory. We conclude that expecting leapfrog stages of the nexus is unrealistic, as cross-income-level change requires approximately 80% of the population to significant change its livelihood and lifestyle. Therefore, we recommend setting science-based targets for decoupling carbon and pollution emissions from development are necessary, but should be adapted and tailored to each country's local practice.

Journal of Cleaner Production, Volume 449, 10 April 2024, 141782

Abstract

Climate aid is a form of official development assistance that addresses climate change mitigation and adaptation and plays a crucial role in combating climate change. However, existing empirical evidence does not suggest a clear link between climate aid and carbon lock-in. Based on country-level panel data from 77 countries spanning the period 2002–2020, this paper empirically examines the impact of climate aid on carbon lock-in and the four sub-indicators of carbon lock-in. Moreover, we investigate the mediating role of technological progress and potential impact mechanisms. We find that (1) climate aid has a significant restraining effect on carbon lock-in, and is an effective means of inhibiting the four aspects of carbon lock-in, namely, the lock-in of industry, institution, technology, and social behavior. (2) Technological progress not only directly leads to carbon lock-in eradication, but also synergizes with climate aid, suggesting that the combined influence of technological progress and climate aid can enhance the efficacy of efforts to mitigate carbon lock-in. (3) Climate aid promotes carbon lock-in mitigation by accelerating energy structure transition and industrial structure transition, which are two internal impact mechanisms in the nexus between climate aid and carbon lock-in. These findings offer concrete and practical policy implications to facilitate the development of climate aid and carbon lock-in eradication.

Journal of Cleaner Production, Volume 448, 5 April 2024, 141559

Abstract

Air pollution assessment in urban and rural areas is really challenging due to high spatio-temporal variability of aerosols and pollutants and the uncertainties in measurements and modelling estimates. Nevertheless, accurate determination of the pollution sources and distribution of PM2.5 concentrations is especially important for source apportionment and mitigation strategies. This study provides estimates of PM2.5 concentrations across Malaysia in high spatial resolution, based on multi-satellite data and machine learning (ML) models, namely Random Forest (RF), Support Vector Regression (SVR) and extreme Gradient Boosting (XGBoost), also covering remote areas without measurement networks. The study aims to develop ML models that are simpler than previous works and demonstrate computational efficiency. Six sub-models were developed to represent different locations and seasons in Malaysia. Model 1 includes all data from 65 air-quality stations, Models 2 and 3 characterize urban/industrial and suburban sites, respectively, while Models 4 to 6 correspond to dry, wet, and inter-monsoon seasons, respectively. The RF technique exhibited slightly better performance compared to the XGBoost and SVR approaches. More specifically, for model 1, it exhibited a high correlation with a coefficient of determination (R2) of 0.64 and RMSE of 12.17 μg m−3, while similar results were obtained for models 3, model 4 and model 5. The lower performance (R2 = 0.16–0.94) observed in the wet and inter-monsoon seasons is due to fewer number of data used in model calibration. Integration of two AOD products from the Advanced Himawari Imager (AHI) and Visible Infrared Imaging Radiometer Suite (VIIRS) sensors together with gases pollutants from Sentinel 5P enabled seamless seasonal PM2.5 mapping over Malaysia, even for a short period of time. However, usage of data with insufficient information during the model training procedure, and lack of satellite data due to cloud contamination, can limit the PM2.5 prediction accuracy.

Journal of Environmental Management, Volume 356, April 2024, 120563

Abstract

The connection between income inequality and environmental degradation remains a topic of persistent debate, marked by inconsistencies in both theoretical and empirical studies. This study offers a novel contribution to this discourse by investigating the simultaneous influences of renewable energy and income inequality on environmental degradation. Utilizing data from 158 nations from 2000 to 2017, our research reveals a crucial moderating role of renewable energy in the nexus between income inequality and environmental degradation. The study's key finding is that the impact of income inequality on environmental degradation is contingent on the level of renewable energy development. In scenarios with limited renewable energy, income equality leads to increased environmental degradation. However, when renewable energy is more developed, income equality contributes to reducing environmental degradation. This novel insight suggests that renewable energy development can mitigate the trade-off between pursuing income equality and environmental sustainability, thereby enabling their simultaneous achievement. The research also highlights that a more equitable income distribution enhances the environmental benefits of renewable energy. Further analysis demonstrates the significant role played by household consumption behavior and social norms in shaping this phenomenon. By adding these new dimensions to the existing literature, the study significantly enriches the understanding of the complex interplay among economic factors, renewable energy, and environmental sustainability.

Journal of Cleaner Production, Volume 448, 5 April 2024, 141666

Abstract

Understanding the spatio-temporal interactions between ecosystem services (ESs) and the progress of Sustainable Development Goals (SDGs) is crucial in arid regions due to the more intense conflicts between human well-being and environmental performance. However, the interactions over distance and their spatial connectivity network among regions are often neglected, influencing the advancements in policy making especially in arid basin. Here a comprehensive framework that integrated ESs and SDGs was proposed to assess the spatial coupling between human well-being and environmental performance within and across regions in the Heihe River Basin (HRB), the second largest inland river basin in China. Then the Random Forests method was employed to identify the key driving factors of the interactions. The results are as follows: (1) The coupling that accounts for both local and distant effects was higher than that only considers local effects. The interactions of all regions that considered both were more balanced, suggesting that spatial interactions among regions promoted the supplies of ES and the progress of SDGs. (2) The midstream of HRB formed a stronger spatial connectivity network. (3) Land use intensity, population density, and water scarcity showed a strong influence on the interactions. This study provides targeted suggestions to guide sustainable development for better human well-being while maintaining ecosystem health for better environmental performance.

Journal of Environmental Management, Volume 356, April 2024, 120421

Abstract

China is currently confronted with the dilemma of achieving its green development goals while maintaining economic growth. The National Ecological Demonstration Zones (NEDZs) represent an innovative attempt by local governments to balance economic development with ecological civilisation, potentially offering a solution to this issue. This study calculated the Green Total Factor Productivity (GTFP) for 1925 districts and counties from 1999 to 2018. Using the selection of NEDZs as a quasi-natural experiment, a difference-in-differences model was employed to empirically analyse the impact of NEDZs on GTFP. The results indicated that the establishment of NEDZs led to an average increase in GTFP of 0.2175 compared to the control group. The primary mechanisms involved are innovation, structure, and enforcement. Moreover, the green development effects of the NEDZs exhibited regional heterogeneity. Compared to the western regions, the central and eastern regions showed limited green development effects. Areas with smaller populations, lower human capital, and lower administrative levels demonstrated significant improvements after the implementation of the NEDZ. Further analysis reveals a significant spatial agglomeration pattern of GTFP and the NEDZs exert a strong ‘siphon effect’ on the GTFP of neighbouring areas. This study provides a new perspective on the GTFP research and offers theoretical and practical evidence for assessing the impact of NEDZs.

Journal of Cleaner Production, Volume 449, 10 April 2024, 141688

Abstract

The inherent unpredictability of economic policies can create a challenging environment for businesses and government. Such uncertainties may, in turn, have repercussions on environmental quality efforts. Accordingly, this study thoroughly explores the intricate relationships among several vital variables: economic policy uncertainty (EPU), economic growth, natural resource rent (NRR), renewable energy consumption (REC), and environmental quality. The geographical focus of this investigation is four Nordic economies (Sweden, Finland, Norway, and Denmark). The research method is firmly anchored in the STIRPAT framework, with a notable innovative twist. The CS-ARDL simulations estimate the long-term interaction between the series. One key advantage of the estimation model is the ability and robustness to handle reverse causality and endogeneity concerns in time-series econometric models. The empirical findings from this research demonstrate that EPU, economic growth, and NRR are primary indicators of increased CO2 emissions. These factors collectively contribute to the escalating trend of carbon emissions within the Nordic nations. In stark contrast, clean energy consumption emerges as a promising factor that not only counters the rising emissions trend but actively contributes to environmental quality. The importance of transitioning towards cleaner energy sources becomes evident in light of these findings. Policy-makers should recognize that economic policy uncertainty can be a potent driver of environmental pollution and should prioritize formulating transparent and consistent policies that attract investments in clean energy solutions.

Environmental Pollution, Volume 346, 1 April 2024, 123642

Abstract

Mitochondria are bioenergetic, biosynthetic, and signaling organelles in eukaryotes, and contain their own genomes, mitochondrial DNA (mtDNA), to supply energy to cells by generating ATP via oxidative phosphorylation. Therefore, the threat to mitochondria’ integrity and health resulting from environmental exposure could induce adverse health effects in organisms. In this review, we summarized the association between mtDNA copy number (mtDNAcn), and environmental exposures as reported in the literature. We conducted a literature search in the Web of Science using [Mitochondrial DNA copy number] and [Exposure] as two keywords and employed three selection criteria for the final inclusion of 97 papers for review. The consensus of data was that mtDNAcn could be used as a plausible biomarker for cumulative exposures to environmental chemical and physical agents. In order to furtherly expand the application of mtDNAcn in ecological and environmental health research, we suggested a series of algorithms aiming to standardize the calculation of mtDNAcn based on the PCR results in this review. We also discussed the pitfalls of using whole blood/plasma samples for mtDNAcn measurements and regard buccal cells a plausible and practical alternative. Finally, we recognized the importance of better understanding the mechanistic analysis and regulatory mechanism of mtDNAcn, in particular the signals release and regulation pathways. We believe that the development of using mtDNAcn as an exposure biomarker will revolutionize the evaluation of chronic sub-lethal toxicity of chemicals to organisms in ecological and environmental health research that has not yet been implemented.

Journal of Cleaner Production, Volume 449, 10 April 2024, 141821

Abstract

Smart energy plays an important role in alleviating energy poverty in China in the context of the new technological revolution and industrial change. This paper uses China's smart pilot policy as a quasi-natural experiment, employing China's provincial panel data from 2011 to 2022, measuring energy poverty indices based on a projection pursuit evaluation model, and conducting a quasi-natural experiment using a synthetic control method to assess the effect of smart energy on energy poverty and specific mechanisms of action. The study found that smart energy has a specific and significant impact on energy poverty, but the effect differs in different regions depending on the construction cycle and energy endowment. In the mechanism test, smart energy significantly alleviates energy poverty through the mechanisms of improving energy supply capacity, improving energy payment capacity, and improving energy cleanliness. The results of the study provide empirical references for regional solutions to energy poverty and the planning of smart energy construction.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141395

Abstract

The complementary utilization of different energy sources is a promising strategy for consuming excess electricity and improving system efficiency. In this study, complementary utilization of electricity and natural gas is proposed for a hydrogen production system based on chemical recuperation. The system uses electrolysis technology to convert excess electricity generated from intermittent and fluctuating renewable energy into green hydrogen. It also utilizes the by-product oxygen for oxy-fuel combustion to achieve near-zero carbon dioxide emissions after subsequent compression, transportation, and storage. The system uses natural gas for steam methane reforming to generate hydrogen. A portion of flue gas generated by the combustor is introduced into the reformer, replacing high-temperature steam for reforming with methane. In addition, the waste heat from the flue gas is introduced into the electrolysis cell to save electricity. Energy and exergy analyses of the proposed and reference systems were performed. The results revealed that the energy and exergy efficiencies of the proposed system are 81.20% and 73.29% at near-zero carbon dioxide emission, representing an improvement of 7.09 and 6.41 percentage points, respectively, compared to the reference system. It also appeared that 98.68% in situ oxygen consumption was achieved. The hydrogen mass flow generated by the proposed system is 33.83 kg/h, which is 8.78% higher than the 30.88 kg/h of the reference system. This study introduces a promising method for developing a hydrogen production system with high efficiency and near-zero carbon dioxide emissions.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141444

Abstract

E-commerce has been disrupting the retail marketplace with its rapid growth in India over the past few years. Multiple socio-economic factors, including the Digital India initiative, the transition towards a cashless economy, and the rise in consumer electronics and internet users, were crucial in creating a shift in consumer perceptions favouring e-commerce. One of the hidden consequences of e-commerce acceptance is the rising packaging plastic problem. It has typically employed unwanted secondary and tertiary packaging, often considered necessary for transportation. E-commerce has also given rise to multiple shopping instances, which were previously non-existent and thus contributed to excessive packaging plastic waste. However, until recently, the e-commerce sector in India has managed to escape the shackles of the plastic waste management legislation and was considered a free rider. This study aims to investigate the key factors aiding the growth of the e-commerce sector, the packaging plastic problems amplified by the e-commerce sector, the legislative backdrop, and a case study on how various e-commerce platforms have adapted to the changing policy landscapes. A multi-faceted solution integrating optimisations at the pre-shipping, post-shipping and legislative framework levels is proposed. The recommendation from this study can trigger a transformative change in reducing the packaging plastic waste generation and creating a sustainable e-commerce industry in the country.

URBAN ENVIRONMENT/ MÔI TRƯỜNG ĐÔ THỊ 

Science of The Total Environment, Volume 919, 1 April 2024, 170710

Abstract

Nowadays, urban planners and decision-makers are confronted with an increasing number of major urban spaces whose functioning is accompanied by a high density of domestic, private and professional activities, all associated with the consumption of fossil fuels and the emission of atmospheric pollutants and greenhouse gases. As centers of activity and zones of economic and demographic resources, urban centers stand out as privileged areas for the implementation of local strategies aiming at reducing air pollutant emissions, whether through spatial planning, the evolution of services or the transformation of practices. In this work, we propose a diagnosis of the links between population, urban forms, mobility and air pollutant emissions, using the OLYMPUS activity-based emission model. The model is run over two distinct French regions, Pays de la Loire and Île-de-France, characterized by contrasting urban characteristics in terms of structure, density and accessibility. The results highlight the good transposability of the OLYMPUS model over different territories. Then, the interconnections between the specificities of urban systems on one side and the travel demand, modal share, mobility patterns and total road emissions on the other side, are explored. We notably show that the densification of urban centers exerts a pull on peri-urban areas, generating car trips from the suburbs and worsening air quality in the urban cores. The results underline the importance of targeted emission reduction strategies taking into account the unique characteristics and challenges of specific urban landscapes.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141405

Abstract

As sustainable urban communities continue to seek alternative energy sources, this study explores the inclusion of renewable resources in the energy mix. With a focus on liquefied natural gas (LNG) regasification, parabolic trough solar collectors, dual-loop power cycles, proton exchange membrane electrolysis, and hydrogen liquefaction cycle, this research conducts a comprehensive examination of an integrated system. The primary objective is to provide a diverse range of valuable outputs, including electricity, liquefied hydrogen, desalinated water, and cooling for coastal areas. Through careful analysis of regional geographic features, San Francisco emerges as a suitable location due to its favorable solar radiation intensity and existing LNG transportation infrastructure. The findings reveal that the integrated system has the potential to deliver approximately 5750.4 MWh of cooling, 14988.85 MWh of electricity, and 1,491,084 m3 of fresh water, thereby significantly contributing to the city's utility demands. In terms of data-driven optimization, artificial neural networks serve as intermediary mechanisms to establish correlations between the developed code and the optimization algorithm. The results demonstrate that the optimized system exhibits notable improvements in production capacity. Moreover, significant reductions in the levelized cost of electricity (0.19 Cent/kWh), fresh water (1.22 Cent/m3), and hydrogen (0.08 $/kg) are observed. Although the optimized case entails a 16.11% higher cost rate compared to the base system, it is projected to generate a 25.59% higher profit over its operational lifespan. Additionally, the payback period of the optimized system is shortened by 6.31%, making it an attractive long-term investment for sustainable urban development.

Science of The Total Environment, Volume 920, 10 April 2024, 170963

Abstract

The recent La-Nina phase of the El Nino Southern Oscillation (ENSO) phenomenon unusually lasted for third consecutive year, has disturbed global weather and linked to Indian monsoon. However, our understanding on the linkages of such changes to regional air quality is poor. We hereby provide a mechanism that beyond just influencing the meteorology, the interactions between the ocean and the atmosphere during the retreating phase of the La-Niña produced secondary results that significantly influenced the normal distribution of air quality over India through disturbed large-scale wind patterns. The winter of 2022–23 that coincided with retreating phase of the unprecedented triple dip La-Niña, was marred by a mysterious trend in air quality in different climatological regions of India, not observed in recent decades. The unusually worst air quality over South-Western India, whereas relatively cleaner air over the highly polluted North India, where levels of most toxic pollutant (PM2.5) deviating up to about ±30 % from earlier years. The dominance of higher northerly wind in the transport level forces influx and relatively slower winds near the surface, trapping pollutants in peninsular India, thereby notably increasing PM2.5 concentration. In contrast, too feeble western disturbances, and unique wind patterns with the absence of rain and clouds and faster ventilation led to a significant improvement in air quality in the North. The observed findings are validated by the chemical-transport model when forced with the climatology of the previous year. The novelty of present research is that it provides an association of air quality with climate change. We demonstrate that the modulated large-scale wind patterns linked to climatic changes may have far-reaching consequences even at a local scale leading to unusual changes in the distribution of air pollutants, suggesting ever-stringent emission control actions.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141614

Abstract

The rapid urbanization poses the potential risk of overload and collapse for cities. Addressing the problems brought about by rapid urbanization to ensure urban safety and sustainable development has become particularly urgent and crucial, especially for regions with high ecological vulnerability and weak economic foundations. This study utilizes panel data spanning from 2013 to 2020 and applies the entropy weight-TOPSIS model to assess the urban resilience of 54 cities within the Yellow River Basin. It explores the temporal evolution, spatial distribution, and dynamics of urban resilience. Further, through the application of the Geographically and Temporally Weighted Regression model, the research investigates the drivers of urban resilience, considering temporal and spatial variations. Findings indicate a consistent increase in urban resilience across the Yellow River Basin, albeit with widening regional disparities. The spatial pattern of urban resilience exhibits a gradient decline from downstream to midstream and then upstream. The impact of various factors on urban resilience differs by region, with technological innovation emerging as the most influential. To foster a sustainable future, the Yellow River Basin should prioritize technological innovation, particularly in industrial cities, and advocate for the adoption of green technologies to diminish resource consumption and mitigate environmental pollution.

Science of The Total Environment, Volume 922, 20 April 2024, 171325

Abstract

Despite the well-established recognition of the health hazards posed by PM2.5-bound PAHs, a comprehensive understanding of their source-specific impact has been lacking. In this study, the health risks associated with PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) and source-specific contributions were investigated in the urban region of Taipei during both cold and warm seasons. The levels of PM2.5-bound PAHs and their potential health risks across different age groups of humans were also characterized. Diagnostic ratios and positive matrix factorization analysis were utilized to identify the sources of PM2.5-bound PAHs. Moreover, potential source contribution function (PSCF), concentration-weighted trajectory (CWT) and source regional apportionment (SRA) analyses were employed to determine the potential source regions. Results showed that the total PAHs (TPAHs) concentrations ranged from 0.08 to 2.37 ng m−3, with an average of 0.69 ± 0.53 ng m−3. Vehicular emissions emerged as the primary contributor to PM2.5-bound PAHs, constituting 39.8 % of the TPAHs concentration, followed by industrial emissions (37.6 %), biomass burning (13.8 %), and petroleum/oil volatilization (8.8 %). PSCF and CWT analyses revealed that industrial activities and shipping processes in northeast China, South China Sea, Yellow Sea, and East China Sea, contributed to the occurrence of PM2.5-bound PAHs in Taipei. SRA identified central China as the primary regional contributor of ambient TPAHs in the cold season and Taiwan in the warm season, respectively. Evaluations of incremental lifetime cancer risk demonstrated the highest risk for adults, followed by children, seniors, and adolescents. The assessments of lifetime lung cancer risk showed that vehicular and industrial emissions were the main contributors to cancer risk induced by PM2.5-bound PAHs. This research emphasizes the essential role of precisely identifying the origins of PM2.5-bound PAHs to enhance our comprehension of the related human health hazards, thus providing valuable insights into the mitigation strategies.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141385

Abstract

Carbon peaking is a research hotspot in China, aiming to reduce the impact of human activities on global climate change, promote the transformation of Low-carbon economy and realize high-quality development. The article takes Wuxi City in China's Jiangsu Province as a pilot low-carbon city to study its carbon emissions characters, then introduces the KAYA model, and sets different scenarios for the influencing factors, further predicts carbon emissions peak in 2019∼2030, and finally proposes the corresponding carbon reduction pathways. Results show that the total of carbon emissions in the study area is still in the upward period of the Kuznets' inverted U-shaped curve, the main factors are population growth rate, economic growth rate, energy consumption intensity and energy structure. If the enhanced carbon reduction scenario is adopted, carbon emissions peak will occur in 2025 or 2026, and the total carbon emissions will be between 120 million tCO2 e to 130 million tCO2 e, and the per capita carbon level will be about 17.5–19.5 tCO2 e. On the future, ten emission reduction pathways for China's low-carbon cities are put forward: strengthening urban spatial planning, upgrading economic structure, developing low-carbon systems in energy, industry, housing, transportation, and agriculture, encouraging low-carbon lifestyles, reforming low-carbon boosting mechanism, and improving low-carbon governance capability.

Science of The Total Environment, Volume 922, 20 April 2024, 171265

Abstract

The role of agricultural versus vehicle emissions in urban atmospheric ammonia (NH3) remains unclear. The lockdown due to the outbreak of COVID-19 provided an opportunity to assess the role of source emissions on urban NH3. Concentrations and δ15N of aerosol ammonium (NH4+) were measured before (autumn in 2017) and during the lockdown (summer, autumn, and winter in 2020), and source contributions were quantified using SIAR. Despite the insignificant decrease in NH4+ concentrations, significantly lower δ15N-NH4+ was found in 2020 (0.6 ± 1.0‰ in PM2.5 and 1.4 ± 2.1‰ in PM10) than in 2017 (15.2 ± 6.7‰ in PM2.5), which indicates the NH3 from vehicle emissions has decreased by∼50% during the lockdown while other source emissions are less affected. Moreover, a reversed seasonal pattern of δ15N-NH4+ during the lockdown in Changsha has been revealed compared to previous urban studies, which can be explained by the dominant effect of non-fossil fuel emissions due to the reductions of vehicle emissions during the lockdown period. Our results highlight the effects of lockdown on aerosol δ15N-NH4+ and the importance of vehicle emissions to urban atmospheric NH3, providing conclusive evidence that reducing vehicle NH3 emissions could be an effective strategy to reduce PM2.5 in Chinese megacities.

Journal of Cleaner Production, Volume 448, 5 April 2024, 141704

Abstract

During the rapid urbanization process, the unequal distribution of green spaces (GS) has become a prominent topic in academic discussions due to its implications for social justice. Nonetheless, the equity of GS availability among different types of residential neighborhoods remains unclear, posing a challenge to achieving environmental justice in urban greening practices. This study, taking Shenzhen as a case study, examines the equity of GS availability between urban villages (UV) and residential quarters (RQ), two common residential neighborhood types in Chinese cities. We initially categorized both inner-GS and outer-GS based on their location inside or outside the boundary of residential neighborhoods and assessed GS availability at various accessible distances. Subsequently, the Theil index was applied to evaluate the inequity of GS availability, encompassing both the inequities within and between UV and RQ. Our findings reveal that UV exhibited higher GS inequity than RQ across all accessible distances. Furthermore, within UV, GS inequity decreased as the accessible distance increased, while the opposite trend was observed for RQ. Notably, although significant inequities existed in inner-GS availability between UV and RQ, outer-GS played a crucial role in mitigating this imbalance. These results provide valuable insights into GS equity across different residential neighborhood types and offer recommendations for enhancing/balancing the equity of GS availability in Shenzhen.

Journal of Environmental Management

Volume 356, April 2024, 120561

Abstract

Recorded particulate matter (PM2.5) hourly trends are compared for fifteen urban recording sites distributed across central England for the period 2018 to 2022. They include 10 urban-background and five urban-traffic (roadside) sites with some located within the same urban area. The sites all show consistent background and peak distributions with mean annual values and standard deviations higher for 2018 and 2019 than for 2020 to 2022. The objective of this study is to demonstrate that trend attributes extracted from hourly recorded univariate PM2.5 trends at these sites can be used to provide reliable short-term hourly predictions and provide valuable insight into the regional variations in the recorded trends. Fifteen trend attributes extracted from the prior 12 h (t-1 to t-12) of recorded PM2.5 data were compiled and used as input to four supervised machine learning models (SML) to forecast PM2.5 concentrations up to 13 h ahead (t0 to t+12). All recording sites delivered forecasts with similar ranges of error levels for specific hours ahead which are consistent with their PM2.5 recorded ranges. Forecasting results for four representative sites are presented in detail using models trained and cross-validated with 2020 and 2021 hourly data to forecast 2021 and 2022 hourly data, respectively. A novel optimized feature selection procedure using a suite of five optimizers is used to improve the efficiency of the forecasting models. The LASSO and support vector regression models generate the best and most generalizable hourly PM2.5 forecasts from trained and validated SML models with mean average error (MAE) of between ∼1 and ∼3 μg/m3 for t0 to t+3 h ahead. A novel overfitting indicator, exploiting the cross-validation mean values, demonstrates that these two models are not affected by overfitting. Forecasts for t+6 to t+12 h forward generate higher MAE values between ∼3 and ∼4 μg/m3 due to their tendency to underestimate some of the extreme PM2.5 peaks. These findings indicate that further model refinements are required to generate more reliable short-term predictions for the t+6 to t+24 h ahead.

Journal of Cleaner Production, Volume 448, 5 April 2024, 141672

Abstract

A decrease in population is an emerging challenge in China's urbanization trajectory. This study utilizes data from the Sixth and Seventh Population Censuses to identify Chinese cities experiencing population decline, focusing on prefecture-level cities. It employs 30 indicators relevant to nine Sustainable Development Goals (SDGs) concerning urban areas and populations to evaluate the progress of these shrinking cities in 2010 and 2020. A novel metric, "SDG population elasticity", is introduced to quantify the association between population reduction and SDG indexes. The study employs K-means++ clustering for 130 shrinking cities. The findings reveal that out of the 130 cities, 63 exhibit a downward trend in SDG index scores, predominantly in China's northeast and western regions. The Northeast region has negative SDG population elasticity, indicating a lag in sustainable development compared to that in other areas. Additionally, the research categorizes China's shrinking cities into four groups: cities with strong population elasticity feedback-significantly declining SDGs, cities with weak population elasticity feedback-slightly regressing SDGs, cities with high population loss-negative SDGs in decline, and cities with smart population decline-steady SDGs growth. These findings offer a foundation for crafting bespoke policies in shrinking cities to ensure a balanced approach to sustainable development and monitor advancement toward achieving the SDGs.

Journal of Environmental Management, Volume 356, April 2024, 120467

Abstract

Urban flood risk assessment delivers invaluable information regarding flood management as well as preventing the associated risks in urban areas. The present study prepares a flood risk map and evaluate the practices of low-impact development (LID) intended to decrease the flood risk in Shiraz Municipal District 4, Fars province, Iran. So, this study investigate flood vulnerability using MCDM models and some indices, including population density, building age, socio-economic conditions, floor area ratio, literacy, the elderly population, and the number of building floors to. Then, the map of thematic layers affecting the urban flood hazard, including annual mean rainfall, land use, elevation, slope percentage, curve number, distance from channel, depth of groundwater, and channel density, was prepared in GIS. After conducting a multicollinearity test, data mining models were used to create the urban flood hazard map, and the urban flood risk map was produced using ArcGIS 10.8. The evaluation of vulnerability models was shown through the use of Boolean logic that TOPSIS and VIKOR models were effective in identifying urban flooding vulnerable areas. Data mining models were also evaluated using ROC and precision-recall curves, indicating the accuracy of the RF model. The importance of input variables was measured using Shapley value, which showed that curve number, land use, and elevation were more important in flood hazard modeling. According to the results, 37.8 percent of the area falls into high and very high categories in terms of flooding risk. The study used a stormwater management model (SWMM) to simulate node flooding and provide management scenarios for rainfall events with a return period ranging from 2 to 50 years and five rainstorm events. The use of LID practices in flood management was found to be effective for rainfall events with a return period of less than 10 years, particularly for two-year events. However, the effectiveness of LID practices decreases with an increase in the return period. By applying a combined approach to a region covering approximately 10 percent of the total area of Shiraz Municipal District 4, a reduction of 2–22.8 percent in node flooding was achieved. The analysis of data mining and MCDM models with a physical model revealed that more than 60% of flooded nodes were classified as "high" and "very high" risk categories in the RF-VIKOR and RF-TOPSIS risk models.

Journal of Cleaner Production, Volume 449, 10 April 2024, 141562

Abstract

Achieving urbanization sustainability is considered to be both an important component of the Sustainable Development Goals and a key way to address the conflict between limited resource constraints and urban continued growth. Regarding the urbanization sustainability, the impact of ecological environment and resource consumption has been widely discussed, while the holistic effect of urban land expansion and urban population dynamics is under-researched. This paper evaluated the urbanization sustainability of 15 urban agglomerations in China from 2000 to 2020, and applied the Geodetector model to investigate its impact mechanism. The results show that at the national level, the level of urbanization sustainability exhibited a trend of first increasing and then decreasing, accompanied by significant spatial differentiation. Spatially, the level of urbanization sustainability in urban agglomerations located in the northeast regions had strong variability during the study period. In contrast, urban agglomerations located in the central region had a lower level of urbanization sustainability due to the unrestricted expansion of urban land. In addition, urbanization sustainability varied according to the development stage of urban agglomerations. Specifically, urbanization sustainability showed a downward trend in the initial development stage, early growth stage and later growth stage of urban agglomeration, and upward trend in mature stage. Economic development level, foreign direct investment, industrial structure and urbanization level were the primary determinants of differences in urbanization sustainability at both national and regional levels. These findings may help to formulate the urban sustainable development planning and differentiated land use policies.

Environmental Pollution, Volume 346, 1 April 2024, 123543

Abstract

The study focused on detecting and characterizing microplastics in outdoor and indoor air in Ranchi, Jharkhand, India during post-monsoon (2022) and winter (2023). Stereo microscopic analysis showed that plastic fibres had a dominant presence, fragments were less abundant, whereas fewer films could be detected in indoor and outdoor air. The atmospheric deposition of microplastics outdoors observed 465 ± 27 particles/m2/day in PM10 and 12104 ± 665 and 13833 ± 1152 particles/m2/day in PM2.5 in quartz and PTFE, respectively during the post-monsoon months. During winter, microplastic deposition rates in PM10 samples were found to be 689 ± 52 particles/m2/day and 19789 ± 2957 and 30087 ± 13402 in quartz and PTFE particles/m2/day respectively in PM2.5. The mean deposition rate in indoor environment during post-monsoon was 8.3 × 104 and 1.03 × 105 particles/m2/day in winter. During the post-monsoon period in PM10, there were fibres from 7.7 to 40 μm and fragments from 2.3 μm to 8.6 μm. Indoor atmospheric microplastics, fibres ranged from 1.2 to 47 μm and fragments from 0.9 to 16 μm present respectively during the post-monsoon season. Fibres and fragment sizes witnessed during winter were 3.6–6.9 μm and 2.3–34 μm, respectively. Indoor air films measured in the range of 4.1–9.6 μm. Fourier transform infrared analysis showed that outdoor air contained polyethylene, polypropylene, Polystyrene, whereas indoor air had polyvinyl chloride. Polyethylene mainly was present in outdoor air, with lesser polypropylene and polystyrene than indoors, where polyvinyl chloride and polyethylene were in dominant proportions. Elemental mapping of outdoor and indoor air samples showed the presence of elements on the microplastics. The HYSPLIT models suggest that the particles predominantly were coming from North-West during the post-monsoon season. Principal component analysis indicated wind speed and direction influencing the abundance of microplastics. Microplastics concentration showed strong seasonal influence and potential to act as reservoir of contaminants.

Journal of Cleaner Production, Volume 449, 10 April 2024, 141554

Abstract

The degradation of ecosystems poses a significant threat to human well-being, necessitating the urgent protection of ecosystem services (ES). The incorporation of social perceptions into the assessment of ES benefits is paramount in environmental management. However, scant attention has been directed towards investigating the relationship between urban streets and resident's perception of ES benefits. Using the central urban area in Guangzhou as a case study, this research proposes a perceived ES benefits prediction method based on machine learning. The perception of ES benefits in Guangzhou was successfully predicted from street view images and perception data. "Food and material provision”, "aesthetic enjoyment”, "recreation”, and "ecological security” are the most readily perceived ES in urban streets. Spatial analysis further revealed the spatial dependence between the perceived ES benefits and street view characteristics. All perceptions of ES benefits exhibit uneven spatial aggregation patterns in the research area. "Greenness”, "openness” and "scene diversity” are key driving variables spatially related to ES benefits perception. The results of this study contribute valuable insights for practitioners in the field of ecosystem services and offer guidance to urban planners in making informed decisions for the development of sustainable urban ecosystems.

Environmental Pollution, Volume 346, 1 April 2024, 123518

Abstract

Pregnant women are highly vulnerable to environmental stressors such as ambient particulate matter (PM). Particularly during their 3rd trimester, their bodies undergo significant oxidative stresses. To further consolidate this dialogue into practice, the current study evaluated healthy pregnant women (n = 150 housewives; 18–40 years old; gestation age >36 weeks) from the highly polluted city of Yazd, Iran, from September to November 2021. The aerosol optical depth (AOD) data retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS) were employed as influencing variables and validated using field-collected PM10 data (r = 0.62, p-value <0.01). The links between blood platelet count, enzymes (SGOT, SGPT, LDH, bilirubin), metabolic products (urea and acid uric) and different combinations of AOD data were assessed using the Generalized Additive Model. The results showed a high temporal variability in AOD (0.94 ± 0.51) but a spatially stable distribution pattern. The mean AOD during the 3rd trimester, followed by that of the three-month peak, were identified as the most significant non-linear predictors, while the mean AOD during the 1st trimester and throughout the entire pregnancy showed no significant associations with any of the biomarkers. Considering the associations found between AOD variables and maternal oxidative stresses, urgent planning is required to improve the urban air quality for sensitive subpopulations.

Journal of Cleaner Production, Volume 449, 10 April 2024, 141641

Abstract

Natural hazards could have devastating consequences globally, making hazard assessment and spatial prediction crucial for enhancing the resilience of urbanized regions. However, current disaster prediction and assessment research often neglect the compound effects between multiple geohazards highly in urbanized regions. To address the concern, we employed comparative methodology, evaluating four machine learning algorithms—Extreme Gradient Boosting (XGBoost), Random Forest (RF), Back Propagation Neural Network (BP), and Long Short-Term Memory (LSTM)—in the creation of Geohazard Susceptibility Maps (GSM) for the highly urbanized Guangdong-Hong Kong-Macao Greater Bay Area (GBA). Additionally, the study investigated the triggering mechanisms and the compound interaction between multiple geohazards using the conditional vine copula model. The results showed that the XGBoost model outperformed other models (AUC = 0.89) for predicting multiple geohazards. Geohazards were predominantly concentrated in urban areas in the GBA, with surface subsidence being the most severe, followed by collapse and landslide. The primary triggers for multi-geohazards include distance to roads, slope length, and lithology, with slope length and lithology identified as the primary causative factors in urban areas. Urbanization within the GBA increased the probability of multi-geohazards by 10%, compared to their univariate counterparts. Urban regions exhibited increased risks of landslides, surface subsidence, and collapse by approximately 31%, 44%, and 32%, respectively compared to non-urban regions. Additionally, compound geohazards in the GBA were primarily triggered by heavy rainfall, resulting in the formation of landslide-collapse and collapse-landslide geohazard chains. The probability of compound geohazards is approximately 5% lower than that of univariate geohazards. This is because compound geohazards necessitate a higher cumulative rainfall, and the rainfall threshold was approximately 2–3 times higher than that of univariate geohazards. In the cascading hazard pattern, the occurrence of primary geohazards during local heavy rain increased the probability of secondary geohazards by approximately 10%. The study provides essential insights for mitigating compound geohazards in urbanized areas.

INDUSTRIAL AREA ENVIRONMENT / MÔI TRƯỜNG KHU CÔNG NGHIỆP 

Science of The Total Environment, Volume 919, 1 April 2024, 170559

Abstract

Volatile organic compounds (VOCs) play a major role in O3 formation in urban environments. However, the complexity in the emissions of VOCs and nitrogen oxides (NOx) in industrial cities has made it challenging to identify the key factors influencing O3 formation. This study used observation-based-model (OBM) to analyze O3 sensitivities to VOCs and NOx during summer in a typical industrial city in China. The OBM model results were coupled with a receptor model to analyze the sources of O3. Higher concentrations of O3 precursors were observed during polluted periods indicating that precursor accumulation contributed to the higher maxima of the net ozone formation rate and HOx concentrations. Analyses of ROx· budgets and relative incremental reactivity (RIR) indicated that O3 production is in a chemical transition regime and was sensitive to both VOCs and NOx. Results from Positive Matrix Factorization (PMF) analysis indicated that gasoline vehicle emissions, industrial processes, and coal combustion were major sources of O3 precursors. The sensitivities of O3 production to these sources depend on if both VOC and NOx sensitivities are considered. If only VOCs sensitivity is considered, in contrast, the contribution of anthropogenic sources to O3 production was significantly underestimated. This study highlights the importance of accounting for both VOCs and NOx sensitivities when O3 chemistry is in a transition regime in O3 production attribution studies.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141421

Abstract

The increasing burden of government spending on food safety regulation has been acknowledged as a common challenge faced by regulatory agencies in a multitude of countries. The Chinese government has significantly invested in food safety regulations in recent years. However, the food safety situation has not been effectively optimized, and a high proportion of food enterprises continue to have repeated food quality issues. Achieving sustainable food safety governance necessitates the attainment of dual goals: enhancing regulatory efficiency and reducing regulatory burdens. These issues have not been thoroughly investigated in the academic literature. This study aims to identify the key factors that contribute to the repeated production violations by food enterprises amid stricter regulations and to explore methods to address this issue. The study employs a Logit model to examine the pivotal factors influencing repeated production violations of food enterprises and utilizes a DID model to assess the impact of food safety regulatory information interventions on the recurrence of these violations. The study has found that: (1) The cognitive bias of food enterprises regarding the stringency of food safety inspections is a significant factor in the repeated production violation of food enterprises. Additionally, government punishment positively moderates the relationship between this cognitive bias and the occurrence of violations. (2) Interventions involving the dissemination of food safety regulatory information can effectively mitigate the recurrence of violation behaviors in food production. For each additional target of information intervention, the rate of repeated production violations by food enterprises decreases by 11.9 percentage points. The study provides theoretical substantiation and practical insights to support the Chinese government's twin objectives of improving the efficiency of food safety regulation and reducing the associated regulatory burdens.

Environmental Research, Volume 246, 1 April 2024, 118069

Abstract

Heavy metals and metalloids (HMMs) inhibit the biodegradation of organic pollutants. The degree of inhibition depends not only on the concentration and bioavailability of HMMs but also on additional factors, such as environmental variables (e.g., inorganic components, organic matter, pH, and redox potential), the nature of the metals, and microbial species. Based on the degradation pattern and metal concentrations causing half biodegradation rate reductions (RC50s), the inhibition of biodegradation was: Hg2+, As2O3 > Cu2+, Cd2+, Pb2+, Cr3+ > Ni2+, Co2+ > Mn2+, Zn2+ > Fe3+. Four patterns were observed: inhibition increases with increasing metal concentration; low concentrations stimulate, while high concentrations inhibit; high concentrations inhibit less; and mild inhibition remains constant. In addition, metal ion mixtures have more complex inhibitory effects on the degradation of organic pollutants, which may be greater than, similar to, or less than that of individual HMMs. Finally, the inhibitory mechanism of HMMs on biodegradation is reviewed. HMMs generally have little impact on the biodegradation pathway of organic pollutants for bacterial strains. However, when pollutants are biodegraded by the community, HMMs may activate microbial populations harbouring different transformation pathways. HMMs can affect the biodegradation efficiency of organic pollutants by changing the surface properties of microbes, interfering with degradative enzymes, and interacting with general metabolism.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141475

Abstract

Mine haul roads are the unpaved roads that are constructed from the overburden materials obtained from the mining operations and are used for the movement of heavily loaded dumpers and trucks. The haul roads constructed from this overburden material shows continuous distress in the form of over ruts, potholes, and shear failures, creating major issues in the movement of dumpers. In the present research study, an experimental investigation was conducted based on mechanistic empirical design to evaluate the strength-deformation characteristics, durability, and environmental emissions of cement stabilized overburden soil of a local mine. The unconfined compression tests were conducted at cement dosages varying from 1 to 6% of dry soil mass and increase in the unconfined compressive strength were examined at different intervals of time until 28 days of the curing period. In the case of static triaxial tests, the enhancement in undrained shear strength and elastic modulus of stabilized specimens was determined in comparison to the untreated specimens, whereas in cyclic triaxial tests, the reduction in permanent deformations and increase in resilient modulus were evaluated under different confining pressures and cyclic deviatoric stresses. An empirical model has been proposed to predict the long-term rutting of overburden under repeated loading. The proposed model is based on the behaviour of various parameters, such as applied cyclic deviatoric stress, number of load repetitions, loading frequencies, and on the permanent deformation characteristic of mine overburden soil. In addition, durability and environmental sustainability aspects of the treatment has also been studied to determine the optimal dose of cement.

Environmental Research, Volume 246, 1 April 2024, 118001

Abstract

In recent years, extensive research endeavors are being undertaken for synthesis of an efficient, economic and eco-friendly cerium oxide nanoparticles (CeO2 NPs) using plant extract mediated greener approach. A number of medicinal plants and their specific parts (flowers, bark, seeds, fruits, seeds and leaves) have been found to be capable of synthesizing CeO2 NPs. The specific key phytochemical constituents of plants such as alkaloids, terpenoids, phenolic acids, flavones and tannins can play significant role as a reducing, stabilizing and capping agents in the synthesis of CeO2 NPs from their respective precursor solution of metal ions. The CeO2 NPs are frequently using in diverse fields of science and technology including photocatalytic degradation of dyes, antibiotics as well as antimicrobial applications. In this review, the mechanism behind the green synthesis CeO2 NPs using plant entities are summarized along with discussion of analytical results from characterization techniques. An overview of CeO2 NPs for water remediation application via photocatalytic degradation of dyes and antibiotics are discussed. In addition, the mechanisms of antimicrobial efficacy of CeO2 NPs and current challenges for their sustainable application at large scale in real environmental conditions are discussed.

Journal of Cleaner Production, Volume 448, 5 April 2024, 141733

Abstract

Natural fibres are in great demand as a clean and green material as reinforcement in sustainable and environment-friendly biodegradable composites. The study aimed to extract palm grass leaf fibres through water retting, a cleaner and greener approach compared with the use of 5–10% NaOH. The physicochemical characterisation was done by SEM, optical microscopy, FT-IR, XRD, TGA, bundle strength, moisture content and standard biochemical tests for cellulose, hemicellulose, lignin and ash. New natural fibres extracted from Curculigo capitulata by water retting showed a smooth surface of uniaxial fibres under SEM and optical microscope compared to eroded surfaces of chemically extracted fibres. Both the fibres extracted by water retting and with 5% NaOH showed nearly similar crystallinity index (84–85%) and size (2.44nm), whereas the former contained 64% cellulose with bundle strength 154MPa compared to 72% and 219.11MPa with the latter. While using 10% (NaOH) showed cellulose 82.29 ± 0.63%, crystallinity index 87.43%, and bundle strength 256.46 ± 15.81MPa. Approximately similar lignin content (20.30 ± 0.91–21.66 ± 1.18%) and mass degradation (%) were obtained in water-retted and 5%–7.5% NaOH extracted fibres. FT-IR spectra showed the characteristic bands at 3421cm−1 for O–H stretching and 2917cm−1 for alkyl C–H stretching in cellulose; at 1630cm1 for Cdouble bondC stretching in lignin. All the extracted fibres showed industrial potential similar to successful natural fibres for fine rope, yarn, handmade paper, and fabrics aiming for a circular bioeconomy.

Environmental Research, Volume 247, 15 April 2024, 118134

Abstract

Urbanization-related human activities, such as population aggregation, rapid industrial expansion, and intensified traffic, are key factors that impact local polycyclic aromatic hydrocarbon emissions and their associated health risks. Consequently, regions with varying degrees of urbanization within a megacity may exhibit diverse spatiotemporal patterns in the presence and distribution of soil polycyclic aromatic hydrocarbons, resulting in different levels of ecological risks for local inhabitants following the same period of development. In this study, we measured the concentrations of 16 polycyclic aromatic hydrocarbons in soil samples collected from industrial district and rural district in Tianjin (China) in 2018, and compared with polycyclic aromatic hydrocarbon data in 2001 from a previous study to characterize these regional variations in occurrence, source, and human risk of polycyclic aromatic hydrocarbons induced by urbanization with time and space. The results indicate the 20-year rapid urbanization and industrialization has differentially affected the composition, distribution and sources of polycyclic aromatic hydrocarbons in soils from different economic functional zones in Tianjin. Additionally, its impact on health risks in rural district appeared to be more significant than that in industrial district.

Journal of Cleaner Production, Volume 448, 5 April 2024, 141642

Abstract

Green finance, clean technology innovation (CTI), and environmental tax are all eco-friendly measures for diminishing environmental degradation. Few studies have examined how these variables work together to realize the object of green growth (GG). Therefore, this research aims to examine the role of the above factors in achieving GG by using 28 developed countries from 1995 to 2019. These countries have passed over a time of fast progress at the expense of heavy pollution and hence have moved their emphasis to GG. This paper starts with the construction of the GG index based on entropy-weighted TOPSIS, followed by pooled OLS, fixed effect, random effect, the two-step least-square estimator (2SLS), and the System GMM models for hypothesis testing. From the findings, it is obsense of that: (1) Green finance positively affects GG; the higher the levels of GG, the greater the enhancement of green finance on GG. (2) CTI favorably mediates the impact of green finance on GG, and the mediating effect accounts for 14.06% of the overall effect. (3) Environmental tax has a significant threshold effect on the link between green finance and CTI; when high levels of environmental taxes are maintained, the influence of green finance on enterprises' CTI is greatly strengthened, with an increase of 53%. GG will be further promoted by the advancement of enterprises' CTI. Finally, emerging counties would benefit from this study in designing frameworks of green finance, environmental tax, and CTI policies to achieve GG.

Environmental Pollution, Volume 347, 15 April 2024, 123702

Abstract

The quantification of microplastic (MP) pollution in rivers is often constrained by a lack of historical data on a multi-decadal scale, which hinders the evaluation of public policies. In this study, MP contents and trends were analyzed in dated sediment cores sampled upstream and downstream of a large metropolis, in environmental deposits that exhibited consistent sedimentation patterns from the 1980s to 2021. After a thorough sedimentological analysis, MPs were quantified in samples by micro Fourier Transform InfraRed spectroscopy (μFTIR imaging) and a density separation and organic matter digestion procedure. Microplastics recorded in the upstream core are relatively ubiquitous all along the dated sequence. The results also confirmed a sever increase of microplastics levels in the downstream core, by one order of magnitude, and an increase of polymer types. Polypropylene, polyethylene, and polystyrene represent ubiquitous contamination and were predominant at the two stations, whereas polyvinyl chloride and polytetrafluoroethylene were suspected to be abundant at the downstream station, but were not detected at the upstream station. Their presence could be linked to local contamination from specific industrial sources that manufactured and utilized these polymers. Surprisingly, in the downstream station sediment has recorded a relative improvement in polymers associated with industrial sources since the 2000s and, to a lesser extent, for ubiquitous ones since the 2010s. This trend of mitigation diverges from that of global assessments, that assume uncontrolled MP pollution, and suggest that European Union wastewater policy and regulation on industrial discharges have positively influenced water quality, and certainly also on MPs. However, the accumulation of microplastics remains high in recent deposits and raises the emerging concern of the long-term management of these reservoirs.

Journal of Cleaner Production, Volume 449, 10 April 2024, 141649

Abstract

Recycling of industrial wastes into value-added functional materials is a sustainable route for industrial waste management. This study proposed a revolutionary design of low-carbon radiation shielding functional composites by incorporating iron-rich industrial waste as precursor and heavy aggregates. Experimental results showed that the iron-rich industrial waste-enhanced radiation shielding functional composites (IWRSC) reached a high compressive strength of 43.2 MPa after 3-day heat curing. Characterization analyses indicated that the alkali-active components dissolved from industrial waste aggregates reacted with the alkali-activator to generate abundant geopolymer gels, resulted in the improvement in the interfacial transition zone. Besides, the gamma ray shielding capability of IWRSC was 21.2% better than that of normal composite, due to the high density of industrial waste aggregates and the dense microstructure of IWRSC. The carbon emission and energy consumption of composites were reduced by 64.4% and 69.6% by replacing natural heavy aggregates with industrial waste heavy aggregates. The unit cost of IWRSC was only 95.9 $/m3, which was 95.0% lower than that of barite-incorporated counterpart. Thus, this novel solution can effectively recycle industrial wastes into functional composites in a sustainable way, contributing to zero-waste city construction and the realization of a circular economy.

Journal of Environmental Management, Volume 356, April 2024, 120533

Abstract

This paper examines the impact of air pollution control policies targeting key polluting enterprises, highlighting a strategic shift towards precision pollution control that concentrates on high-emission, high-risk businesses. The paper explores the efficacy of these policies and their potential spatial spillover effects, utilizing panel data from 259 Chinese cities from 2013 to 2021. Employing the difference-in-differences (DID) model and spatial Durbin model, the study analyzes both the direct local effects and the broader spatial consequences of these regulatory measures on air quality. The findings indicate a significant reduction in air pollutant concentrations in urban areas, attributing this improvement to factors such as industrial restructuring, increased investment in science and technology, and economic growth. Spatial econometric analysis further reveals a substantial positive correlation in air quality among Chinese cities. However, estimates of the spillover effect indicate that while such policies successfully reduce pollution locally, they could unintentionally degrade air quality in adjacent areas. The study highlights the need for nuanced policy strategies to mitigate unintended spatial spillovers and enhance overall effectiveness. It recommends tailored policies that integrate environmental and socioeconomic objectives, national and regional coordination for consistent enforcement, technology-driven compliance strategies, and incentives for sustainable enterprise practices.

Journal of Cleaner Production, Volume 449, 10 April 2024, 141714

Abstract

To meet increasingly stringent standards of Nitrogen oxide (NOx), it is highly desirable to develop high-efficiency denitration technology during hazardous waste incineration. Therefore, a state-of-art decoupling combustion technology of liquid hazardous wastes (LHW) has been proposed to achieve low NOx emission. In this technology, LHW is introduced into a low-NOx reactor to reduce NOx generated from solid hazardous waste (SHW) incineration prior to its complete combustion. The present article is devoted to clarifying the optimal conditions for denitration reactions by LHW, so the capabilities of nitric oxide (NO) reduction by reduction by LHW model compounds, namely methanol and methylbenzene, were evaluated in fixed-bed and fluidized-bed reactors. The highest denitration efficiency is 78.9% at 900 °C for methanol and 70.0% at 1000 °C for methylbenzene in the test temperature range. The NO reduction activities were closely associated with cracking characteristics of LHW. The presence of oxygen (O2) exhibited different effects on denitration: it promoted NO reduction at low temperatures due to the generation of more denitration-favored agents but suppressed NO reduction at high temperatures due to the oxidation of denitration-favored agents into CO2 and H2O by excessive O2. Moreover, the fluidized-bed reactor, characterized by good heat transfer, exhibited an approximately 17% higher NO reducing efficiency compared to the fixed-bed reactor at low temperatures, but both reactors demonstrated similar NO reduction efficiencies of around 83% at high temperatures. In addition, methanol and methylbenzene showed higher NO reduction efficiencies than their cracking-produced reducing gases, with the reducing gases accounting for approximately 50% of the overall NO reduction efficiency at 1000 °C. According to the above results, a two-step denitration reaction pathway was proposed in which both cracking-formed free radicals and reducing gases contribute to the overall NO reduction. The results of this study can provide valuable insights for NO reduction in the hazardous waste disposal.

Journal of Environmental Management, Volume 356, April 2024, 120531

Abstract

This paper interprets the implicit carbon flows in global industrial sectors from a network perspective. Using the SNA-IO integrated model, along with cross-border input-output data from Eora26 (2000–2020) and global energy balance data, the implicit carbon emissions of global industrial sectors and their evolution are analyzed. A carbon emission network structure from an industrial chain perspective is proposed. The results indicate that the carbon emissions responsibility of an industry is not only associated with its own energy consumption. It also involves the carbon emissions transfer resulting from the exchange of products and services between upstream and downstream industries. Block model analysis reveals the carbon emission transfer relationships and their interconnections among global industrial sectors, tending towards an industry clustering pattern where "production side” converges with "demand side” coexisting in supply and demand. There are noticeable inequalities in wealth gains and environmental burdens between these blocks. This paper can provide targeted carbon reduction policy recommendations for various industrial sectors to participate in global responsibility allocation and promote the formation of a low-carbon global industrial sector network.

Journal of Cleaner Production, Volume 447, 1 April 2024, 141275

Abstract

As the path of industrial eco-efficiency (IEE) needs to be re-examined from a multi-dimensional perspective, this research opens the internal "black box” of China's industrial eco-economic system driven by sustainable development goals (SDGs) and decomposes IEE into industrial production and sustainable development stages. It further divides the industrial production stage into two parallel subsystems of water use efficiency (WUE) and energy efficiency (EE) and derives SDG6 efficiency (SDG6E) and SDG7 efficiency (SDG7E) in the sustainable development stage respectively. The paper proposes a meta two-stage parallel entropy dynamic DDF-DEA model to re-measure IEE of 30 provinces in China from 2015 to 2021, discusses the relationship between overall efficiency and stage efficiency, and by using the Tobit model explores various types of influencing factors by subregion. The results show that the modified DDF-DEA model can explore China's IEE more accurately under SDGs. China's IEE is more stable from 2015 to 2021, with the efficiency value always fluctuating between 0.59 and 0.64, the overall level is low, and there is more room for improvement. There are significant inter-provincial differences in IEE and efficiency inertia. In more than 75% of the provinces SDG7E constrains IEE improvement, while the dynamic evolution of IEE and its subsystem efficiency varies across regions. Environmental regulation is a common factor affecting IEE across the country and in the east, central, and west regions, whereas the level of economic development, openness to the outside world, and urbanization rate are differential factors affecting IEE across the country and in the three major regions. This study offers new perspectives for exploring the path of IEE enhancement and providing empirical references for the collaborative construction of industrial ecological civilization.

Journal of Environmental Management, Volume 356, April 2024, 120559

Astract

In November 2015, a catastrophic rupture of the Fundão dam in Mariana (Brazil), resulted in extensive socio-economic and environmental repercussions that persist to this day. In response, several reforestation programs were initiated to remediate the impacted regions. However, accurately assessing soil health in these areas is a complex endeavor. This study employs machine learning techniques to predict soil quality indicators that effectively differentiate between the stages of recovery in these areas. For this, a comprehensive set of soil parameters, encompassing 3 biological, 16 chemical, and 3 physical parameters, were evaluated for samples exposed to mining tailings and those unaffected, totaling 81 and 6 samples, respectively, which were evaluated over 2 years. The most robust model was the decision tree with a restriction of fewer levels to simplify the tree structure. In this model, Cation Exchange Capacity (CEC), Microbial Biomass Carbon (MBC), Base Saturation (BS), and Effective Cation Exchange Capacity (eCEC) emerged as the most pivotal factors influencing model fitting. This model achieved an accuracy score of 92% during training and 93% during testing for determining stages of recovery. The model developed in this study has the potential to revolutionize the monitoring efforts conducted by regulatory agencies in these regions. By reducing the number of parameters that necessitate evaluation, this enhanced efficiency promises to expedite recovery monitoring, simultaneously enhancing cost-effectiveness while upholding the analytical rigor of assessments.

Science of The Total Environment, Volume 919, 1 April 2024, 171000

Abstract

The exponential growth in textile fiber production and commensurate release of textile waste-based effluents into the environment has significant impacts on human wellbeing and the long-term planetary health. To abate these negative impacts and promote resource circularity, efforts are being made to recycle these waste materials via conversion into adsorbents for water decontamination. This review critically examines plant- and regenerated cellulose-based fibers for removing water pollutants such as heavy metals, dyes, pharmaceutical and petrochemical wastes. The review reveals that chemical modification reactions such as grafting, sulfonation, carboxymethylation, amination, amidoximation, xanthation, carbon activation, and surface coating are normally employed, and the adsorption mechanisms often involve Van der Waals attraction, electrostatic interaction, complexation, chelation, ion exchange, and precipitation. Furthermore, the adsorption processes and thus the adsorption mechanisms are influenced by factors such as surface properties of adsorbents, pollutant characteristics including composition, porosity/pore size distribution, specific surface area, hydrophobicity/hydrophobicity, and molecular interactions. Besides, feasibility of the approaches in terms of handling and reuse, environmental fate, and economic impact was evaluated, in addition to the performances of the adsorbents, the prospects, and challenges. As current cost analysis is non-exhaustive, it is recommended that researchers focus on extensive cost analysis to fully appreciate the true cost effectiveness of employing these waste materials. In addition, more attention must be paid to potential chemical leaching, post-adsorption handling, and disposal. Based on the review, fiber precursors and textile fiber wastes are viable alternative adsorbents for sustainable water treatment and environmental management, and government entities must leverage on these locally accessible materials to promote recyclability and circularity.