To understand the transport patterns and major sources of ozone (Osub.3) in Nanjing, this study carried out the 48-hour backward trajectories of air masses in Nanjing from March 2021 to March 2022, ...based on the HYSPLIT backward trajectory model driven by GDAS global reanalysis data. The primary transmission routes and putative source locations of Osub.3 pollution in Nanjing were determined through the integration of trajectory clustering analysis, potential source contribution function (PSCF), and concentration-weighted trajectory (CWT) analysis with meteorological data and Osub.3 concentration data. The results showed that the high Osub.3 concentrations and exceedance rates in Nanjing were in late spring and early summer, with the highest in June. The diurnal variation of Osub.3 concentrations in all seasons exhibited a single peak with a maximum from 13:00 to 16:00. The southeasterly flow passing through Zhenjiang, Changzhou, Wuxi, Suzhou, and Shanghai dominated the Osub.3 pollution in Nanjing. The PSCF and CWT presented a high consistency of Osub.3 potential sources in Nanjing. Zhenjiang, Ma'anshan, Changzhou, Wuxi, Suzhou, and Huzhou were identified as the main potential source regions of Osub.3 pollution in Nanjing. This study provides accurate theoretical references for regional joint prevention and control of Osub.3 pollution in Nanjing.
Most governmental initiatives in India, to leash down urban air pollution, have yielded little results till date, largely due to purely technocratic vision, which is shrouded by technological, ...economic, social, institutional, and political hardships. We present this reflective article on urban greenery, as a proposition to urban authorities (e.g., pollution regulators, environmental systems’ managers, urban landscape planners, environmental policy makers), shift from purely technocratic way of thinking to
thinking with nature
, by strategic greening of urban spaces, for long-term air pollution prevention and control measures. To that end, we offer a meta-analysis of recent (post 2005) global literature using four-stage PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) approach. We open the narrative by briefing about main pollutant filtration mechanisms by trees, followed by cognitive aspects of species selection (e.g., deciduous vs. evergreen, air pollution tolerance index, environmental stressors). Till date, most Indian studies on urban greenery mostly but focused on physiological aspects of trees. Here, we draw attention of urban authorities to an equally compelling, but yet less explored, aspect: design criteria, with reference to two most common urban configurations, namely, street canyon and open road. With pictorial depictions, we enumerate various categories of street canyons and discuss aspect ratio (building height to street width) and various wind flow regimes (isolated roughness, wake interface, and skimming), that the urban authorities should be cognizant about to maximize pollutant removal efficiency. For open road, we discuss vegetation barriers, with special emphasis on canopy porosity/density functions. In the final sections, we reflect on a potential systems’ thinking approach for on-ground implementation, comprising of revamping of urban forestry programs, research and development, community mobilization and stakeholder engagement, and strategic outreach. In addition, we emphasize on means to harness co-benefits of urban greenery, beyond mere pollutant removal, to garner support from urban residents’ communities. Last but not the least, we also caution the urban authorities about the undesirable outcomes of urban greenery that will require more process-level research.
Identifying potential sources of pollution in tributaries and determining their contribution rates are critical to the treatment of water pollution in main streams. In this paper, we conducted a ...multivariate statistical analysis on the water quality data of 12 parameters for 3 years (2018–2020) at six sampling sites in the Laixi River to qualitatively identify potential pollution sources and quantitatively calculate the contribution rates to reveal the tributaries’ pollution status. Spatio-temporal cluster analysis (CA) divided 12 months into two parts, corresponding to the lightly polluted season (LPS) and highly polluted season (HPS), and six sampling sites were divided into two regions, corresponding to the lightly polluted region (LPR) and highly polluted region (HPR). Principal component analysis (PCA) was used to determine the potential sources of contamination, identifying four and three potential factors in the LPS and HPS, respectively. The absolute principal component score-multiple linear regression (APCS-MLR) receptor model quantitatively analyzed the contribution rates of identified pollution sources, and the importance of the different pollution sources in LPS can be ranked as domestic sewage and industrial wastewater and breeding pollution (33.80%) > soil weathering (29.02%) > agricultural activities (20.95%) > natural influence (13.03%). HPS can be classified as agricultural cultivation (41.23%), domestic sewage and industrial wastewater and animal waste (33.19%), and natural variations (21.43%). Four potential sources were identified in LPR ranked as rural domestic sewage (31.01%) > agricultural pollution (26.82%) > industrial effluents and free-range livestock and poultry pollution (25.13%) > natural influence (14.82%). Three identified latent pollution sources in HPR were municipal sewage and industrial effluents (37.96%) > agricultural nonpoint sources and livestock and poultry wastewater (33.55%) > natural sources (25.23%). Using multivariate statistical tools to identify and quantify potential pollution sources, managers may be able to enhance water quality in tributary watersheds and develop future management plans.
Soil heavy metal pollution threatens ecological health and food security. It is significant to classify pollution risk management and control zones, which can effectively cope with soil pollution and ...scientifically carry out soil remediation projects. In this study, based on 665 soil samples collecting from Ningbo (southeast China), single pollution index and Nemerow composite pollution index (NCPI) were measured to assess soil pollution risk, and self-organization mapping model was applied to classify management and control zones. Results showed that the heavy metal pollution in the northwest part was more serious, while the east part was less polluted. Although more than 75% soil samples had negligible risks, the Hg and Cu pollution was greatly influential and notable as their polluted samples accounted for 24.21% and 12.48% respectively. Moreover, about 55.34% soil samples and more than half study region had pollution grades, and NCPI values were obviously high with the center of northwest study area. Results also showed that the study region could be classified into four zones with good spatial variabilities. Specifically, Monitored Zone with High-risk Pollution had the highest NCPI caused by human activities, while Controlled Zone with Severe Pollution had relatively high NCPI caused by industrial and agricultural production. Protected Zone with Ecological Conservation and Restricted Zone with Potential Pollution had low NCPIs attributing to historical or natural factors. Our study implies that the classified zones can provide fundamental and momentous information for establishing appropriate priorities of heavy metal risk management and control.
Nonpoint source pollution (NPSP) has always been the dominant threat to regional waters. Based on empirical models of the revised universal soil loss equation and the phosphorus index, an NPSP risk ...assessment model denoted as SL-NPSRI was developed. The surface soil pollutant loss was estimated by simulating the rain-runoff topographic process, and the influence of path attenuation was quantified. A case study in the Yellow River Delta and corresponding field surveys of soil pollutants and water quality showed that the established model can be applied to evaluate the spatial heterogeneity of NPSP. NPSP usually occurs during high-intensity rainfall periods and in larger estuaries. Summer rainfall increased pollutant transport into the sea from late July to mid-August and caused estuarine dilution. Higher NPSP risks often correspond to coastal areas with lower vegetation coverage, higher soil erodibility, and higher soil pollutant concentrations. Agricultural NPSP originating from cropland significantly increase the pollutant fluxes. Therefore, area-specific land use management and vegetation coverage improvement, and temporal-specific strategies can be explored for NPSP control during source-transport hydrological processes. This research provides a novel insight for coastal NPSP simulations by comprehensively analyzing the soil erosion process and its associated pollutant loss effects, which can be useful for targeted spatiotemporal solutions.
Graphical Abstract
Pesticides are indispensable in agricultural production. They have been used by farmers to control weeds and insects, and their remarkable increases in agricultural products have been reported. The ...increase in the world's population in the 20th century could not have been possible without a parallel increase in food production. About one-third of agricultural products are produced depending on the application of pesticides. Without the use of pesticides, there would be a 78% loss of fruit production, a 54% loss of vegetable production, and a 32% loss of cereal production. Therefore, pesticides play a critical role in reducing diseases and increasing crop yields worldwide. Thus, it is essential to discuss the agricultural development process; the historical perspective, types and specific uses of pesticides; and pesticide behavior, its contamination, and adverse effects on the natural environment. The review study indicates that agricultural development has a long history in many places around the world. The history of pesticide use can be divided into three periods of time. Pesticides are classified by different classification terms such as chemical classes, functional groups, modes of action, and toxicity. Pesticides are used to kill pests and control weeds using chemical ingredients; hence, they can also be toxic to other organisms, including birds, fish, beneficial insects, and non-target plants, as well as air, water, soil, and crops. Moreover, pesticide contamination moves away from the target plants, resulting in environmental pollution. Such chemical residues impact human health through environmental and food contamination. In addition, climate change-related factors also impact on pesticide application and result in increased pesticide usage and pesticide pollution. Therefore, this review will provide the scientific information necessary for pesticide application and management in the future.
Chelating agents may decrease the extent of Ni phytoextraction by reducing plant growth and soil health due to Ni toxicity during enhanced phytoextraction. Contrarily, inducing acidity in the ...rhizosphere of Ni-accumulating plants with plant growth-promoting rhizobacteria (PGPR) having rhizosphere acidification ability can enhance Ni phytoextraction by increasing Ni bioavailability in the soil, plant growth, and plant stress tolerance. We investigated the efficacy of a PGPR species with rhizosphere acidification potential, named Bacillus sp. ZV6 (ARB), in enhancing Ni phytoextraction by white willow (Salix alba) from a Ni-affected soil. The plants were grown for 120 days in soil with zero, threshold, and moderate Ni pollution levels (0, 50, and 100 mg Ni kgsup.−1 soil, respectively) with and without ARB inoculation. After harvest, the effects of the treatments on rhizosphere acidification and associated Ni bioavailability in this zone, Ni distribution in plants, and Ni removal from the soil were investigated. Moreover, enzyme activity, count of bacteria, biomass of microbes, and organic C in the soil, together with indices of plant growth and antioxidant defense, were evaluated. The ARB inoculation significantly improved the plant parameters and soil health and reduced plant oxidative stress at each Ni level compared to the treatments lacking ARB. Besides lowering the soil pH and increasing Ni bioavailability in the rhizosphere with respect to the bulk zone, ARB inoculation exerted additional effects. Surprisingly, the Ni 100 + ARB treatment induced the highest decrease in soil pH (0.32 unit) and an increase in DPTA-extractable Ni (0.45 mg kgsup.−1 soil) between that measured in the bulk zones and that obtained in the rhizosphere zone. Ni distribution in plant parts and Ni removal (% of total Ni) from the soil were also significantly improved with ARB inoculation, compared to the Ni treatments without ARB. The extent of Ni removal was similar for the Ni 50 + ARB (0.27%) and Ni 100 + ARB (0.25%) treatments. Concluding, ARB-inoculated Salix alba can remove similar amounts of Ni from the soil, irrespective of the Ni pollution level.
The study of marine environments inevitably involves considering the problem of marine pollution, which includes questions that focus on the essential need to ensure the long-term health of these ...exceptional ecosystems and the lives and livelihoods they support. The open access textbook "Marine Pollution: monitoring, management and mitigation" approaches these questions in a practical and highly readable format. It gives newcomers to the field background and perspective through the first comprehensive, multidisciplinary exploration of the topic. The topic is indeed complex, requiring the integration of the natural sciences and chemistry with management, policymakers, industry and all of us who are users of the marine environment. The textbook was written by leading experts to especially prepare graduates for a career in marine pollution studies. At the same time, it is relevant for anyone invested in the marine environment with a will to reduce their impacts. The chapters can easily be used independently and are also connected through the cross-referencing of related content. The introductory chapter provides a historical account of marine pollution and explores the fundamental physicochemical conditions of seawater. Two full chapters cover the requisite resources for ensuring success in field and laboratory studies. Then, chapter by chapter the book dives into to the various types of marine pollutants. In closing, it discusses the challenges of understanding multiple stressors and presents mitigation and restoration practices, along with a global overview of marine pollution legislation. We envisioned this textbook as being open access for the very reason we created it: this topic calls for global contributions and champions, and financial restraints should not limit access to this knowledge.
![Study on O[sub.3] Variation...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1687-9309/small "Study on O[sub.3] Variations in Nanjing and the Surrounding Source Analysis")
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