Research on the current strategic interaction of local governments in air pollution control is a key breakthrough. Based on the theory of Chinese style decentralization, this paper puts forward a theoretical framework to explain the incomplete enforcement of air pollution regulation. Using the panel data of 30 provinces in China from 2004 to 2016, this study employs spatial Durbin model, empirically tested the inter-regional strategic interaction of air pollution regulation, and further explores the effect of performance assessment indicators on this strategic interaction. The main conclusions of this paper are as follows: (1) Empirical results confirm that adjacent provinces do exist strategic interaction of air pollution regulation. Furthermore, the strategic interaction of air pollution regulation belongs to complementarities. (2) Meanwhile, from a regional perspective, due to the low level of economic development stock and the low level of air pollution, the interaction effect of air pollution regulation strategies in northwestern region is weaker than that in southeastern region. (3) In addition, under the national sample and the southeast sample, the air environment performance assessment indicators weaken the inter-regional strategic interaction of air pollution regulation, and economic performance assessment indicators on the contrary.

Having knowledge about household environmental behaviors is important for planning and conducting efforts to reduce carbon footprint. In this study, the relationship between environmental awareness, purchasing, household practices, and carbon footprint was investigated, and the impact of demographics on these variables was determined. The analysis shows that sensitivity dimension of environmental awareness is related to few environmental behavior variables (purchasing and efficiency) whereas willingness dimension was related to all variables (except gas). While improvements in demographic factors (income, education, and female employment status) positively affect environmental sensitivity, they increase carbon footprint from automobile. Only increase in income has an effect on willingness. It is determined that income positively affects environmental purchasing. Furthermore, it is revealed that environmental household practices did not differ in terms of demographic characteristics, except the effect of education on pollution.

The microbial fuel cell coupled constructed wetland (CW-MFC) was used for treatment sewage and simultaneously generating electricity. The main aim of this study was to explore the optimal conditions for the treatment of hexavalent chromium (Cr (VI)) wastewater by the CW-MFC system. The performance of CW-MFC in removing Cr (VI) and chemical oxygen demands (COD) contained in wastewater and its electricity generation were studied. Electrode spacing, Cr (VI) and COD concentration, and hydraulic retention time (HRT) had certain effects on the performance of CW-MFC. For the electrode spacing of 10 cm, the highest power density of 458.2 mW/m³ could be obtained with the influent concentration of Cr (VI) (60 mg/L) and COD (500 mg/L). The highest Cr (VI) and COD removal rate were obtained with the HRT of 3 days. Compared with CW system, the electrical energy generated in CW-MFC was beneficial to improving the removal efficiency of COD and Cr (VI). Thus, the results confirmed that CW-MFC is a promising technology to remove Cr (VI) from wastewater and achieve bioelectricity production simultaneously.

To coordinate economic development and carbon emission reduction targets, China needs to improve carbon emission efficiency and upgrade the industrial structure. Therefore, it is important to study the coupling degree and coupling path between these two factors in various provinces in China, and thereby promote the development of China’s low-carbon economy. We first calculate carbon emission efficiency using the Super-SBM model, then analyze an extended coupling model between carbon emission efficiency and industrial structure upgrading, and finally design the coupling paths using the framework of distribution dynamics. There are three main findings. First, the coupling degree of nearly half the provinces is at the level of mild-to-moderate imbalance recession. And in terms of specific coupling characteristics, nearly half the provinces belong to the type “low-level coordination,” with a low development degree and high coordination degree. Second, there is an obvious dynamic imbalance between China’s carbon emission efficiency and industrial structure upgrading, and the “low-level trap” of regional carbon emission efficiency is more serious than that of regional industrial structure upgrading. Finally, if the government prioritizes provinces with low carbon emission efficiency, carbon emission efficiency and the coupling efficiency with industrial structure can be improved, which would not only improve the coupling degree within each region but also alleviate the disharmony between regions.

Considering combinatorial optimality of functional group analysis, speciation, solution chemistry complexity, Pd(II) adsorption–desorption characteristics, this article addresses the competence and efficacy of anion exchange resins namely Amberlite IRA958, Dowex Marathon MSA, Lewatit TP214, and Amberlyst A21 commercial resins. Based on preliminary batch adsorption experiments conducted in the range of 2−10 pH, 0.2−2 g L⁻¹ adsorbent dosage, and 5−1080-min contact time, the optimal adsorption process parameters refer to 4 pH, 1.6, and 1.4 g L⁻¹ adsorbent dosage, and 840- and 720-min contact time for Amberlite IRA958 and Dowex Marathon MSA resins, respectively. Among alternate models, the best-fit models refer to the Freundlich isotherm and pseudo-second-order kinetic models to represent Pd(II) adsorption data obtained for both Dowex Marathon MSA and Amberlite IRA958 resins. Based on the Langmuir isotherm, the maximum monolayer adsorption capacity was evaluated to be 185.16 and 166.67 mg g⁻¹ for Dowex Marathon MSA and Amberlite IRA958 resins, respectively. For model electroless plating solutions as adsorbate system possessing desired solution chemistry complexity and resin cost, nitrogen- and oxygen-containing Amberlyst A21 resin is concluded to be optimal resin. This is not in agreement with the generalized rule of thumb that considers sulfur–nitrogen functional group containing commercial resins to be effective than resins with nitrogen–oxygen functional groups. Due to functional group interactions with the noble metal, no other by-products or exchanged chemicals have been produced in due course of Pd(II) adsorption process, which can be also regarded as an added advantage of the process. Graphical abstract

The study investigates the relationship between air pollution and the status of human mental health using the data of the China Migrant Dynamic Survey (CMDS), 2014. Various econometric methods were used. Particularly, the ordinary least square (OLS) was used to estimate the parametric impact of mental health. Moreover, a robustness test was used to estimate negative impact of air pollution on mental health. Results found that air pollution significantly increased psychological disorder. The concentration of PM2.5 in the air leads to higher prominence of the four negative emotions such as nervous, depression, powerless, and restless or fidgety. After introducing the instrumental variable to solve the endogenous problem, the impact of air pollution on the level of the mental illnesses was still significant and negative. Results are also evident that air pollution has heterogeneity to the negative status of residents’ mental health. Specifically, it has a significant and negative impact on women, rural and urban population, and middle- and low-income groups. The study results suggest that the government must have to revise the environmental regulation policy reduce the negative impact on human health.

To evaluate the hazard assessment of dredging and disposal of sediments, an in-depth chemical and toxicological characterization of sediments was carried out in Venice Lagoon. The bioaccessible and mobile concentration of trace elements in superficial and deep sediments (in the Holocene-Pleistocene limit) can deeply affect the quality of the aquatic ecosystem. Geospeciation and total concentration of trace elements in sediment cores were assessed and several toxicological tests were carried out. The indices of contamination (e.g., geochemical accumulation index, Igₑₒ, pollution load index, PLI) and of speciation (individual contamination factor, ICF and global contamination factor, GCF) were evaluated. Factor Analysis (FA) was performed to explore possible significant correlations between toxicity data and sediment chemistry. Results underlined that the total concentration of trace elements cannot adequately assess the hazard, while bioavailability, mobility, and toxicity of trace elements allow a thorough evaluation of the environmental threats. The integration of results from chemical characterization ex ante and toxicity assays will provide for a better sustainable handling and management of sediments.

Several chemicals present in the aquatic environment have the ability to alter the endocrine system of aquatic organisms, including the metals cadmium (Cd) and zinc (Zn). In males, a tool to analyze this effect is the vitellogenin (VTG) detection, a protein with defined function in the yolk production and subsequent aid to embryo-larval development. This protein is produced just by females and can be detected by simple and cheap methods such as histochemical method. Thus, this study aimed to analyze the capacity of Cd and Zn to induce VTG production in Danio rerio males and determine whether the histochemical labeling method is efficient to study estrogenic effects in this species. For this, D. rerio adult males were exposed chronically (21 days) to 0.25 and 1 μg/L of Cd and 120 and 180 μg/L of Zn, values allowed by the Brazilian and American legislation to aquatic life protection. After which, the organisms were submitted to a histological process as preparation to liver VTG marking by histochemical method and subsequent qualitative analysis of this protein in zebrafish’s liver. After analyzes, it was possible observed that Cd and Zn are capable of inducing VTG production in D. rerio males and that the histochemistry method is efficient for detection of estrogenic effects in this species.

Cadmium (Cd) is one of the toxic metals in the aquatic environment. This study was designed to examine the effects of Cd on the activities of ALT and AST and the concentrations of TP in plasma of freshwater turtle Mauremys reevesii. Experiment turtles were exposed to Cd at the concentration of 15 mg/kg by intraperitoneal injection. The activities of ALT and AST and the concentrations of TP were investigated. Compared with the controls, the activities of ALT and AST in plasma of the treated turtles significantly increased. The concentrations of TP were comparable between the treated turtles and the controls except that were higher than the control turtles in 14 days (14 d) and 56 days (56 d). As a result that turtles exposed to Cd were led to liver function damage.

Biotic interactions shape the community structure and function of ecosystems and thus play an important role in ecosystem management and restoration. To investigate how water temperature (related to the season) and water depth (related to spatial patterns of river morphology) affect macrophyte–bacterioplankton interactions in a groundwater-fed river, we conducted the structural equation modeling on datasets grouped by hydrological conditions. In addition to direct effects on macrophyte growth and/or bacterioplankton development, water temperature and water depth could both regulate the role of different nutrients (inorganic and organic) on affecting these biological indicators. Deeper water depth intensified the positive relationship between macrophytes and bacterioplankton, while higher temperature switched the relationship from being positive to negative. Our study provides empirical evidences that abiotic variables, even with relatively low fluctuations, play a critical role in regulating the patterns and strengths of interaction between macrophytes and bacterioplankton.