Search Results (60)

This study investigates the impact of rural digital economy development on agricultural carbon emission efficiency, aiming to elucidate the intrinsic mechanisms and pathways through which digital technology enables low-carbon transformation in agriculture, thereby contributing to the achievement of agricultural carbon neutrality goals. Based on provincial-level panel data from China spanning 2011 to 2022, this study examines the relationship between the rural digital economy and agricultural carbon emission efficiency, along with its underlying mechanisms, using bidirectional fixed effects models, mediation effect analysis, and Spatial Durbin Models. The results indicate the following: (1) A significant N-shaped-curve relationship exists between rural digital economy development and agricultural carbon emission efficiency. Specifically, agricultural carbon emission efficiency exhibits a three-phase trajectory of “increase, decrease, and renewed increase” as the rural digital economy advances, ultimately driving a sustained improvement in efficiency. (2) Industrial integration acts as a critical mediating mechanism. Rural digital economy development accelerates the formation of the N-shaped curve by promoting the integration between agriculture and other sectors. (3) Spatial spillover effects significantly influence agricultural carbon emission efficiency. Due to geographical proximity, regional diffusion, learning, and demonstration effects, local agricultural carbon emission efficiency fluctuates with changes in neighboring regions’ digital economy development levels. (4) The relationship between rural digital economy development and agricultural carbon emission efficiency exhibits a significant inverted N-shaped pattern in regions with higher marketization levels, planting-dominated areas of southeast China, and digital economy demonstration zones. Further analysis reveals that within rural digital economy development, production digitalization and circulation digitalization demonstrate a more pronounced inverted N-shaped relationship with agricultural carbon emission efficiency. This study proposes strategic recommendations to maximize the positive impact of the rural digital economy on agricultural carbon emission efficiency, unlock its spatially differentiated contribution potential, identify and leverage inflection points of the N-shaped relationship between digital economy development and emission efficiency, and implement tailored policy portfolios—ultimately facilitating agriculture’s green and low-carbon transition. Full article

Atmospheric emissions of industrial-origin trace metals are a major environmental problem that negatively affects air quality and the functioning of forest ecosystems. Traditional air quality monitoring methods require investments in equipment and infrastructure. Indeed, it is difficult to measure most of these pollutants because their concentrations usually occur at very low levels. However, this study explores an ecological approach for low-cost air quality biomonitoring that is based on native biological indicators in the context of the Mediterranean basin. This study aims (i) to evaluate the lichen species composition, diversity, and distribution across three distinct forest sites; (ii) investigate the relationship between lichen species richness and proximity to the pollution source; and (iii) evaluate heavy metal bioaccumulation using a moss species (Funaria hygrometrica) and a lichen species (Xanthoria parietina) as bioindicators of atmospheric pollution. High concentrations of toxic metals were observed along the transect and closer to the pollutant source with marked interspecies variability. X. parietina exhibited high bioaccumulation potential for most toxic metals (Fe, Zn, Pb, Cr, Cu, and Ni) compared to F. hygrometrica with concentrations varying across the three sites, reaching maximum dry-mass values of 6289 µg/g for Fe at the first site and 226 µg/g for Zn at Site 3. Our results suggest that X. parietina can be used as a potential bioindicator for long-term spatial biomonitoring of air quality by determining atmospheric toxic metals concentrations. Full article

The proximity of ecologically valuable areas to industrial zones indicates a strong need for monitoring their condition. Soil assessment involves both molecular techniques for studying microbial biodiversity, such as PCR, sequencing, and metagenomics, as well as parameters of biochemical and enzymatic activity of soil microorganisms. The authors studied the activity of microorganisms responsible for the nitrogen cycle to compare the condition of soils under different uses (wastelands and arable fields) located in the ecologically valuable areas of the Polesie National Park (PNP, protected area) and its surroundings. Additionally, they assessed the suitability of gangue for reclamation and its effectiveness depending on treatment duration (2 and 10 years). In most of the activities analyzed, their levels were lower in the park. A higher intensity of ammonification and nitrification was observed in the soil sampled from the field in the park; however, a reduced N₂O emission was also recorded after incubation in the lab of soil samples collected in the autumn, which may indicate that nitrogen loss from the soil does not occur in this particular habitat, which requires further, long-term and cyclical field trials. These observations confirm the potential protective role of the park in relation to soils and atmosphere in the context of the nitrogen cycle. The activities under study in the reclaimed soils were in both cases lower than in soils from the fields. The current results prove that this method of reclamation is not entirely effective; however, long-term reclamation yielded better results. The present study provided valuable information on the effectiveness of the protective role of the PNP in relation to soils and air. Additionally, these results may be helpful in making decisions regarding the use of waste, such as gangue, for reclamation. Full article

The food industry generates substantial waste, contributing to environmental challenges, such as pollution and greenhouse gas emissions. Utilizing by-products, particularly fruit peels that are rich in fiber, antioxidants, and vitamins, presents a sustainable approach to reducing waste, while enhancing the nutritional value of food products. Specifically, peach peel can be used to produce gluten-free flours, with increased fiber content and antioxidant properties. Extrusion technology is a highly effective method for developing these functional flours, as it improves digestibility, reduces anti-nutrients, and enhances nutrient bioavailability. This study investigates the potential of combining corn flour with peach peel flour, derived from Royal Summer peachs (RSF), at different concentrations (0%, 5%, and 15%). A factorial experimental design was utilized to evaluate the impact of RSF incorporation on the proximate composition, antioxidant capacity, and functional properties of the flour. The results indicate that flours containing 15% RSF demonstrated significant improvements in terms of the dietary fiber content (5.90 g per 100 g⁻¹) and antioxidant capacity (ABTS^•+ 745.33 µmol TE per 100 g⁻¹), meeting the “source of fiber” labelling requirements. The glycemic index of the 15% RSF flour was reduced to 78.09 compared to non-enriched flours. The functional properties of the flour, such as swelling and gelation capacities, were also enhanced with RSF incorporation. These findings highlight the potential of RSF-enriched flours in regard to the development of sustainable, health-promoting, plant-based, and gluten-free flours. Full article

Petroleum refining and petrochemical complexes are significant sources of air pollution, emitting a variety of harmful pollutants with substantial health risks for nearby populations. While much of the information regarding this issue and the potential health impacts of this pollution has been documented, it remains fragmented across studies focusing on specific regions or health outcomes. These studies are often clustered into meta-analyses or reviews or exist as undeclared knowledge held by experts in the field, making it difficult to fully grasp the scope of the issue. To address this gap, our review consolidates the existing knowledge on the sources of air pollution from petroleum refining and petrochemical industries, the main pollutants involved, and their associated health outcomes. Additionally, we conducted an umbrella review of systematic reviews and meta-analysis and also included critical reviews. With this approach, we identified 12 reviews that comprehensively evaluate the health impacts in populations living near petroleum refining and/or petrochemical complexes. These reviews included studies spanning several decades (from 1980 to 2020) and encompassing regions across North America, Europe, Asia, South America, and Africa, reflecting diverse industrial practices and regulatory frameworks. From these studies, our umbrella review demonstrates that residents living near these facilities face elevated risks related to leukemia, lung and pancreatic cancer, nonmalignant respiratory conditions (such as asthma, cough, wheezing, bronchitis, and rhinitis), chronic kidney disease, and adverse reproductive outcomes. Furthermore, we discuss the key challenges in mitigating these health impacts and outline future directions, including the integration of cleaner technologies, which can significantly reduce harmful emissions; strengthening policy frameworks, emphasizing stringent emission limits, continuous monitoring, and regulatory enforcement; and advancing research on underexplored health outcomes. This review emphasizes the need for coordinated global efforts to align the industry’s evolution with sustainable development goals and climate action strategies to protect the health of vulnerable communities. Full article

Social and economic growth in developing countries has heightened the awareness of environmental challenges, with carbon emissions emerging as a particularly pressing concern. However, the impact of economic development on carbon emission intensity has rarely been considered from the perspective of economic agglomeration, and the relationships and mechanisms between the two remain poorly understood. We analyzed the impact of economic agglomeration on carbon emission intensity and its spatial spillover effect in Guangdong Province, the most economically advantaged province of China, based on a spatial weight matrix generated using geographic proximity, exploratory spatial data analysis (ESDA), and the spatial Durbin model. Between 2000 and 2019, economic agglomeration and carbon emission intensity in Guangdong Province exhibited persistent upward trajectories, whereas between 2016 and 2019, carbon emission intensity gradually approached zero. Further, 80% of the province’s economic output was concentrated in the Pearl River Delta region. Strong spatial autocorrelation was observed between economic agglomeration and carbon emission intensity in the cities, and the economic agglomeration of the province had a parabolic influence on carbon emission intensity. Carbon emission intensity peaked at an economic agglomeration level of 1.2416 × 10⁹ yuan/km² and then gradually decreased. The spatial spillover effect of the openness degree on carbon emission intensity was positive, while GDP per capita and industrial structure had negative effects. Further, the economic agglomeration effects of Guangdong Province increased the carbon emission intensity of major cities and smaller neighboring cities. The stacking effect of economic agglomeration between cities also affected the carbon emission intensity of neighboring cities in the region. During the period of rapid urban development, industrial development and population agglomeration increased resource and energy consumption, and positive externalities such as the scale effect and knowledge spillover were not well reflected, resulting in greater overall negative environmental externalities relative to positive environmental externalities. Full article

Soil, geochemical, microbiological, and archeological studies were conducted at eight settlements dating from the Paleolithic to Late Medieval and Modern Ages near the southern Trans-Urals Mountains, Russia. The forest-steppe landscapes, rivers, and abundant mineral resources have attracted people to the region since ancient times. Cultural layers (CLs) are marked by finds of ceramics fragments, animal bones, stone, and metal tools. The properties of CLs include close-to-neutral pH, being well structured, the absence of salinity, enrichment with exchangeable calcium, and anthropogenic phosphorus (0.2–0.4%). The majority of CLs start at a depth of 3–25 cm, extend to 40–60 cm, and contain 6–10% organic carbon (Corg) in the 0–20 cm layer, reflecting carbon input from modern-day processes. At the Ishkulovo site (0.6–0.8 ka BP), Corg decreases to 1.3% because the CL is below 80 cm, and in the absence of fresh organic material input, carbon has been mineralized. The proximity of sites to deposits of copper, chromium, zinc, and manganese in the Ural Mountains creates natural high-content anomalies in the region, as indicated by their abundance in soils and parent rocks. In the past, these elements were also released into CLs from metal products, ceramic fragments, and raw materials used in their manufacture. The sites are quite far (18–60 km) from the Magnitogorsk Metallurgical plant, but industrial stockpiles of S (technogenic coefficient—Ct 30–87%), and, less often, Cr, Mn, and Sr (Ct 30–40%) accumulated in surface layers. These three factors have led to the concentration of pollutants of the first (arsenic, chromium, lead, and zinc) and second (cobalt, copper, and nickel) hazard classes at CLs, often in quantities 2–5 times higher than values for parent materials and geosphere average content (“Clarke” value), and, and less often, more than the allowable content for human health. This may have influenced their health and behavioral functions. Due to the above properties, chernozems have a high buffering capacity and a strong bond with heavy metals. Therefore, no inhibition of microbes was observed. The microbial biomass of the 0–10 cm layer is high, 520–680 µg C/g, and microbes cause the emission of 1.0 C-CO₂ µg/g of soil per hour. During the ancient settlements’ development, a favorable paleoclimate was noted based on the data cited. This contributed to the spread of productive paleolandscapes, ensuring the development of domestic cattle breeding and agriculture. Full article

As the largest carbon-emitting industry in China, the power industry has huge potential for carbon emission reductions. It is vital to study the spatial correlation of carbon emission efficiency in the power industry (CEEP) from a system perspective to understand the interaction mechanisms of CEEP in different provinces. This study applies the SBM-undesirable model to measure the CEEP in China, and a modified Gravity model and social network analysis (SNA) method are applied to analyze the interaction mechanism of the CEEP from a system perspective. Finally, the influencing factors of the CEEP’s spatial correlation are investigated using the quadratic allocation procedure (QAP) method. The results show that (1) the national CEEP is gradually increasing, while the CEEP gap between provinces is widening; (2) the overall network size shows an increasing trend, but the hierarchical structure is somewhat fixed; (3) the central province of a network has a high degree of consistency with the geographically central province, but the spatial spillover effect of the central node provinces on the peripheral provinces is not sufficient; and (4) differences in geographic proximity, energy intensity, and technical level of power generation significantly affect the formation of spatially correlated networks in the CEEP. Full article

Canada, as one of the largest oil and gas producer in the world, is responsible for large emissions of methane, a powerful greenhouse gas. At low levels, methane is not a direct threat to human health; however, human health is affected by exposure to pollutants co-emitted with methane. The objectives of this research were to estimate and map pollutants emitted by the oil and gas industry, to assess the demographic of the population exposed to oil and gas activities, and to characterize the impact of well density on cardiovascular- and respiratory-related outcomes with a focus on Alberta. We estimated that ~13% and 3% people in Alberta reside, respectively, within 1.5 km of an active well and 1.5 km of a flare. Our analysis suggests that racial and socioeconomic disparities exist in residential proximity to active wells, with people of Aboriginal identity and people with less education being more exposed to active wells than the general population. We found increased odds of cardiovascular-related (1.13–1.29 for low active well density) and respiratory-related (1.07–1.19 for low active well density) outcomes with exposure to wells. Close to 100 countries produce oil and gas, making this a global issue. There is an important need for additional studies from other producing jurisdictions outside the United States. Full article

In order to reduce CO₂ emissions from industrial processes, countries have commenced the vigorous development of CCUS (carbon capture, utilization and storage) technology. The high geographical overlap between China’s extensive coal mining regions and CO₂-emitting industrial parks provides an opportunity for the more efficient reduction in CO₂ emissions through the development of Enhanced Coal Bed Methane (ECBM) Recovery for use with CCUS technology. Furthermore, the high geographical overlap and proximity of these regions allows for a shift in the transportation mode from pipelines to tanker trucks, which are more cost-effective and logistically advantageous. The issue of transportation must also be considered in order to more accurately assess the constructed cost function and CCUS source–sink matching model for the implementation of ECBM. The constructed model, when considered in conjunction with the actual situation in Shanxi Province, enables the matching of emission sources and sequestration sinks in the province to be realized through the use of ArcGIS 10.8 software, and the actual transport routes are derived as a result. After analyzing the matching results, it is found that the transportation cost accounts for a relatively small proportion of the total cost. In fact, the CH₄ price has a larger impact on the total cost, and a high replacement ratio is not conducive to profitability. When the proportion of CO₂ replacing CH₄ increases from 1 to 3, the price of CH₄ needs to increase from $214.41/t to $643.23/t for sales to be profitable. In addition, electric vehicle transportation costs are lower compared to those of fuel and LNG vehicles, especially for high-mileage and frequent-use scenarios. In order to reduce the total cost, it is recommended to set aside the limitation of transportation distance when matching sources and sinks. Full article

Poor indoor air quality (IAQ) in schools is associated with pupils’ health and their learning performance. This study aims to provide an overview of the outdoor factors that affect the IAQ in educational settings in order to develop public health measures. We conducted a systematic literature review to investigate the outdoor factors that affect IAQ in educational settings. The selection of articles included 17,082 search string hits from the ScienceDirect database published between 2010 and 2023, with 92 relevant studies selected based on the inclusion and exclusion criteria. Based on a systematic review of the literature, we identified the following outdoor factors: proximity to busy roads, commercial and industrial establishments, meteorological conditions, compounds from the natural environment, emissions from heating buildings, atmospheric reactions and secondary pollutants, unpaved school playgrounds, and smoking. This study provides key information on the mentioned outdoor factors and gives recommendations on measures to reduce classroom pollutant concentrations while highlighting educational settings that require special attention. Our study shows that classroom IAQ is affected by many outdoor pollutant sources, the prevalence of which depends on the educational setting’s micro location. Therefore, it is essential to develop an appropriate classroom ventilation strategy for each educational setting. Full article

Ventilation Air Methane (VAM) significantly contributes to global warming. Capturing and mitigating these emissions can help combat climate change. One effective method is the thermal decomposition of methane, but it requires careful control to prevent explosions from the high temperatures involved. This research investigates the influence of methane concentration and coal dust particle properties on the minimum ignition energy (MIE) required for fugitive methane thermal decomposition and flame propagation properties. This knowledge is crucial for the mining industry to effectively prevent and mitigate accidental fires and explosions in VAM abatement plants. Coal dust samples from three different sources were selected for this study. Experiments were conducted using a modified Hartmann glass tube and a Thermal Gravimetric Analyser (TGA). The chemical properties of coal dust were determined through ultimate and proximate analysis. The particle size distribution was determined using a Mastersizer 3000 apparatus (manufactured by Malvern Panalytical, Malvern, UK). The results showed that the MIE is significantly affected by coal dust particle size, with smaller particles (<74 µm) requiring less energy to ignite compared to coarser particles. Additionally, blending methane with coal dust further reduces the MIE. Introducing methane concentrations of 1% and 2.5% into the combustion space reduced the MIE by 25% and 74%, respectively, for the <74 µm coal dust size fraction. It was observed that coal dust concentration can either raise or lower the MIE. Larger coal dust concentrations, acting as a heat sink, reduce the likelihood of ignition and increase the MIE. This effect was noted at a methane concentration of 2.5% and coal dust levels above 3000 g/m³. In contrast, small amounts of coal dust had little impact on MIE variation. Moreover, the presence of methane during combustion increased the upward flame travel distance and propagation velocity. The flame’s vertical travel distance increased from 124 mm to 300 mm for a coal dust concentration of 300 g·m⁻³ blended with 1% and 2.5% methane, respectively. Full article

The cement industry contributes around 7% of global anthropogenic carbon dioxide emissions, mainly from the combustion of fuels and limestone decomposition during clinker production. Using alternative fuels derived from wastes is a key strategy to reduce these emissions. However, alternative fuels vary in composition and heating value, so selecting appropriate ones is crucial to maintain clinker quality and manufacturing processes while minimizing environmental impact. This study evaluated various biomass and industrial wastes as potential alternative fuels, characterizing them based on proximate analysis, elemental and oxide composition, lower heating value, and bulk density. Sawdust, pecan nutshell, industrial hose waste, and plastic waste emerged as viable options as they met the suggested thresholds for heating value, chloride, moisture, and ash content. Industrial hose waste and plastic waste were most favorable with the highest heating values while meeting all the criteria. Conversely, wind blade waste, tire-derived fuel, and automotive shredder residue did not meet all the recommended criteria. Therefore, blending them with alternative and fossil fuels is necessary to preserve clinker quality and facilitate combustion. The findings of this research will serve as the basis for developing a computational model to optimize the blending of alternative fuels with fossil fuels for cement production. Full article

Forest ecosystems and urban parks are an integral part of the natural environment and the natural system of a city, where they form a mosaic of habitats resulting from the variation in soil cover due to human activities. The study was conducted in urban forests in five urban parks in Upper Silesia (southern Poland) and investigated the chemical properties and content of potentially toxic metals (PTMs) in the topsoil, which had an average thickness of 15 cm for all samples. The soil reaction ranged from acidic (pH = 4.7–5.1, in KCl) to slightly acidic (pH = 5.6, to neutral—6.6–7.2) at most sites. The organic carbon (OC) content was relatively high at all sites, ranging from 1.19 to 14.3%, with the highest total nitrogen (Nt) content being 0.481%. The average total phosphorus (Pt) content in the parks ranged from 310 mg kg⁻¹ to 684 mg kg⁻¹, while the highest values were 1840 mg kg⁻¹. The total Cr, Cu, Co and Ni content was within acceptable limits, while the Zn, Pb, Cd, As, Sr and Ba exceeded acceptable standards. In terms of content, Zn dominated the PTMs at each site (Zn > Pb > Ba > Sr > Cu > Cr > As > Ni > Cd > Co), while Ba and Pb alternated in taking second place (Zn > Ba > Pb > Sr > Cu > Cr > Ni > As > Co > Cd). Environmental indicators, such as the geoaccumulation index (Igeo), enrichment factor (EF) and potential ecological risk index (RI), showed that the analyzed soils are highly contaminated with PTMs. Among the sources of pollution in the urban forest are low emissions from coal combustion, industrial activities, water runoff from streets and proximity to transportation routes. Identification of PTM levels in urban parks will provide valuable information on the behavior of these metals, which is important in sustainable development and can help evaluate the local spatial development plans of urbanized areas. Full article

A sustainable alternative to fossil fuels, cow dung is a renewable energy source that might considerably lower carbon emissions. By modifying its characteristics, such as its gross calorific value (GCV), it could be utilized as a flexible and effective fuel for both industrial and domestic use. To create a fuel composite with a higher heating value, this research examines the heating values and proximate analysis of local cow dung as well as the effects of blending it with agricultural waste. To provide the best heating value, the technique comprises infusing prepared agricultural biomass blends and cow dung at particular ratios. The composite’s quality was enhanced by increasing GCV from 3066 Kcal/kg to 3600 Kcal/kg, increasing volatile matter content, i.e., from 60% to 68%, as well as lowering the ash content of the resultant pellet from 19% to 11%, on average. Full article