Environmental protection and innovation performance are key issues that affect the sustainable development and value growth of cities. Using data of 272 prefecture-level cities during 2002–2016 and 2,169 listed companies, and the air ventilation coefficient and government environmental regulations, as the instrumental variables for PM₂.₅ concentrations, this paper applies two-stage OLS (2SLS) to investigate how air pollution affects China’s technological innovation and its realization mechanism. The results indicate that the rise in air pollution significantly inhibits the technological innovation level of regions as a whole as well as individual enterprises. When considering the spatial effect of the spread of PM₂.₅ concentrations, due to positive spillover effects on innovation activities, the spread of air pollution has negative impacts on technological innovation activities in surrounding cities. Human capital and labour costs are important channels through which air pollution influences China’s technological innovation. The implementation of pilot carbon trading policies can effectively reduce air pollution and then contribute to the achievement of the goals of the green growth strategy.

China’s agriculture is dominated by smallholder farms, which have become major sources of negative environmental impacts including eutrophication, formation of haze, soil acidification and greenhouse gas emissions. To mitigate these environmental impacts, new farming models including family farming, cooperation farming and industrial farming have emerged in recent years. However, whether these new farming practices would improve the economic and environmental performance as compared to the current smallholder farming has yet to be verified on ground level. In this paper, by using pilot farming cases within the watershed of Tai Lake, we found that alternative farming models produced 7% more crop yield, while using 8% less fertilizer, leading to a 28% decrease in pollutant emission per hectare. These alternative farming models have a 17% higher fertilizer use efficiency and 50% higher profit per hectare. Compared to smallholder farming, these alternative farming practices invest 27% more resources into agricultural facilities, including advanced machinery, and have a younger, better educated labor force as a consequence of a larger farm size and more specialization. These input changes substantially increase fertilizer use efficiency and reduce agricultural pollution. Policy arrangements to support and facilitate the uptake of these farming models will further promote the green development and sustainable intensification of agricultural production.

Cephalosporin antibiotics, a group of widely prescribed antibiotics, are frequently detected in wastewater effluent and in the natural aquatic environment. Materials have been sought to effectively degrade the antibiotics. In this study, a novel high-iron clay was prepared with potassium ferrate and montmorillonite via a strong alkaline in situ synthesis method. Degradation of cefazolin sodium (CFZ) by this novel Fe (VI)-clay was investigated. The optimal conditions for the degradation of CFZ were determined using a single factor experiment and response surface optimization method. We found that 89.84% removal efficiency was obtained in 137 min when pH value was 5.16 and Fe (VI)-clay dosage was 0.79 g. The CFZ degradation mechanism was studied by computations on the Frontier Electron Density (FED) in combination with spectroscopic and mass spectroscopic analysis. The spectroscopic characteristics of the products at different stages showed that the oxidation decomposition reaction occurred during the degradation of CFZ by Fe (VI)-clay. Furthermore, FED calculation combined with GC–MS results showed that the degradation pathways of CFZ by the Fe (VI)-clay was mainly the cleavage of β-lactam, thiadiazole, tetrazole, and dihydrothiazine rings.

Coastal basins are the world’s largest ultimate natural system for productivity and more than 40% of the world’s population prefers to live on the coastline. Thus, the coastal region is of great economic and nutritional importance. The current research study investigates the seasonal deviations in coastal water quality at four different locations along the Gulf of Khambhat, Gujarat, India, for three consecutive seasons (pre-monsoon, monsoon, and post-monsoon). The coastal water samples were collected and analyzed for the water quality in the prescribed study area. As a result, sea surface temperature, salinity, pH, EC, alkalinity, turbidity, salinity, total suspended particles, dissolved oxygen, biological oxygen demand, chemical oxygen demand, chloride, sulfate, and nutrients such as nitrate, nitrite, phosphate, and total organic carbon were investigated at Gulf of Khambhat Region. The samples were collected from four different locations (Ghogha, Dumas, Dahej, and Purna). The multivariate statistical analysis indicates that oxygen, dissolved solids, salinity, nutrients, the natural, and anthropogenic conditions are the major factor that affects water quality. The water quality index was calculated to evaluate the seasonal water quality of GoK. The results revealed that the quality of water was moderate in pre-monsoon, monsoon, and post-monsoon. The findings suggest that anthropogenic disturbances and the development of a variety of activities with increased point and non-point stormwater runoff are pumped directly into the coastal areas which damaged water quality. Therefore, the outcomes of physicochemical research of water quality indicators may be a useful tool for government leaders trying to ensure GoK’s long-term sustainability.

The objective of present study was to assess the water quality parameters in two experiments, comprising six configurations of pilot-scale vertical subsurface flow constructed wetlands (VSFCWs) by the comparison of the removal efficiency of organic matter and nutrient pollutants from water in arid region. Effluent treatments were studied in 5-month experiment under different operational conditions including (1) substrate type: sand (S) (experiment 1) or fine gravel (G) (experiment 2) and (2) agronomic species: Phragmites australis (Ph) or Typha latifolia (Ty). This experiment demonstrated that the vegetated wetlands were more efficient than non-planted (Np) ones in terms of removal of TSS, COD, NO₃-N, and TKN from wastewater in the first experiment and more efficient for all water quality parameters except for TSS and BOD₅ in the second experiment. For a given species, the efficiency of both experiments was generally higher with Ph–S than Ph-G and with Ty-S than Ty-G. Regarding unplanted CWs, Np-S performed better than Np-G for all of the tested water quality parameters except TSS. The wetland efficiency indicated that CWs planted with P. australis contributed greatly to the removal of COD, NO₃-N, and TKN in the first experiment, and NO₃-N, NH₄-N, PO₄³-P, and TP in the second experiment, whereas CWs planted with T. latifolia provided the highest removal only with TSS for the first experiment, and COD and TKN for the second experiment. The highest efficiency of unplanted setups (Np-S) was for BOD₅, NH₄-N, PO₄³-P, and TP, while with Np-G was only for TSS and BOD₅. In general, the first experiment is better than the second in removal efficiency for most of the tested parameters. Therefore, the use of sand substrate was more suitable than gravel for wastewater treatment in VSSFCW. As well as, P. australis performed better than T. latifolia for most of the studied parameters.

Previous ecological studies suggest the existence of possible interplays between the exposure to air pollutants and SARS-CoV-2 infection. Confirmations at individual level, however, are lacking. To explore the relationships between previous exposure to particulate matter < 10 μm (PM₁₀) and nitrogen dioxide (NO₂), the clinical outcome following hospital admittance, and lymphocyte subsets in COVID-19 patients with pneumonia. In 147 geocoded patients, we assessed the individual exposure to PM₁₀ and NO₂ in the 2 weeks before hospital admittance. We divided subjects according to the clinical outcome (i.e., discharge at home vs in-hospital death), and explored the lymphocyte-related immune function as an index possibly affecting individual vulnerability to the infection. As compared with discharged subjects, patients who underwent in-hospital death presented neutrophilia, lymphopenia, lower number of T CD45, CD3, CD4, CD16/56 + CD3 + , and B CD19 + cells, and higher previous exposure to NO₂, but not PM₁₀. Age and previous NO₂ exposure were independent predictors for mortality. NO₂ concentrations were also negatively related with the number of CD45, CD3, and CD4 cells. Previous NO₂ exposure is a co-factor independently affecting the mortality risk in infected individuals, through negative immune effects. Lymphopenia and altered lymphocyte subsets might precede viral infection due to nonmodifiable (i.e., age) and external (i.e., air pollution) factors. Thus, decreasing the burden of air pollutants should be a valuable primary prevention measure to reduce individual susceptibility to SARS-CoV-2 infection and mortality.

The environmental planning of cities and rural regions is associated with monitoring the performance of several services, including solid waste management. This study proposes a new framework for the comparative assessment of the performance of integrated municipal solid waste management. The framework includes the fuzzy MACBETH multi-criteria decision-making model used to investigate the uncertainties and inefficiencies associated with solid waste management systems. The model consists of all major stages in solid waste management and its environmental impact. The applicability of the model was examined in the South European region. According to the global fuzzy values of the criteria weights, the most influential reported criteria were GHG emission (0.113,0.157,0.202), the waste generation growth rate (0.034,0.063,0.141), and waste generation (0.034,0.054,0.127). The other results indicated that Italy (47.26) and France (42.67) had shown a better performance, only to be followed by Spain (37.68), whereas Greece (15.77) and Portugal (12.85) had received the lowest score. In the context of promoting the circular economy in Europe, having a higher recycling rate and less landfilling is beneficial for Greece and Portugal. In addition to this, all these countries should make efforts on decoupling the waste generation-GDP correlation. Furthermore, the applicability of the model depends on an appropriate scale and criteria. The model can be replicated to other developed societies with a few modifications. However, it is necessary to modify the criteria for assessing developing societies based on local conditions.

The present study investigated metal and metalloid dynamics in the estuarine water of the Doce River (Brazil) after the collapse of an iron ore-processing tailing dam in 2015. Spectroscopic and isotopic techniques were applied to bring new insights into the effects of the dam failure on the dynamics and hazardousness of particulate and dissolved metal(loid) concentrations along the fluvial-estuarine continuum. Spectroscopic analysis showed that the suspended particulate matter (SPM) of the Doce River estuary consisted of a combination of soil-delivered particles and fine tailing mud particles with small amounts of coarse tailing mud Fe oxides (~150-μm width). Enrichment and contamination factors showed that the dam failure increased particulate Fe, Pb, Cd, and As, and dissolved Pb concentrations. Total concentrations of As (15 μg/L), Pb (30 μg/L), Cd (8 μg/L), and Cr (105 μg/L) increased up to values higher than quality and regulatory guidelines. Human health risk assessment showed that local communities are exposed to a potentially chronic Cr noncarcinogenic effects, although Cr high concentrations were not linked with the dam failure by this study. The particulate Pb isotope signatures reported herein (²⁰⁶/²⁰⁷Pb ratios of 1.214 ± 0.006 and ²⁰⁸/²⁰⁶Pb ratios of 2.025 ± 0.011) can be applied to constrain metal(loid) sources in the Doce River sediment plume and continental shelf. The river-ocean mixing zone caused abrupt changes metal(loid) partitioning (Zn, Pb, Cr, Cu, Cd, and As), controlling their fate in the estuary and the Brazilian southeast coastal.

Excessive phosphorus in water causes eutrophication and leads to the ecological unbalance. The main treatment for eutrophication is to remove the phosphorus in aqua system effectively and efficiently. A composite of fly ash (FA) and metal compound was proposed as the effective sorbent for phosphorus removal, attributed to the active metal compositions and stable structure, as well as the wide source availability of economy. Copper and iron were co-precipitated as a bimetallic compound (BM), well adhered onto fly ash, to acquire the composite sorbent of Cu/Fe-BM@FA. Through the characterizations of XPS, FTIR etc., phosphorus adsorption was achieved mainly upon heterogeneous chemisorption and electrostatic attraction. Consequently, from pH 3 to pH 6, phosphorus of 98% on average was removed in solutions of 0 ~ 40 mg P/L, and the maximum adsorption capacity was up to 32.88 mg/g. Promisingly, the composite sorbent of FA and copper/iron bimetallic compound was a potential and economic selection for phosphorus removal.

Fluoride is one of the most abundant anions in groundwater, posing a significant threat to the safe drinking water supply worldwide. Fluoride contamination in drinking water at levels greater than 1.5 mg L–¹ causes a variety of serious health problems. To address this problem, the current study deals with the synthesis of Mg(OH)₂ nanoflakes by a facile and simple hydrothermal method in the absence of any added template. The sizes of these nanoflakes are in the range of 90 to 200 nm. These nanoflakes are pure and crystalline, possessing hexagonal phase structures. The surface areas of Mg(OH)₂ nanoflakes are varying from 75.8 to 108.1 m² g–¹. These Mg(OH)₂ nanoflakes exhibit excellent adsorption performance for fluoride over a pH range of 2.0 to 9.0 with a maximum Langmuir adsorption capacity of 3129 mg g–¹ at pH 7.0 at 313 K which is the highest for such kind of adsorbent reported so far. The adsorption process is spontaneous and endothermic which primarily follows pseudo-second-order kinetics. The adsorbent is effective in the presence of co-existing anions and is reusable up to the fifth cycle with a minimal loss of adsorption performance. The nanoflakes can effectively remove highly concentrated groundwater fluoride to a permissible limit within a short time which increases the versatility of using these nanoflakes for practical applications.