Blue carbon sinks (mangroves, saltmarshes, and seagrasses) are considered an effective nature-based approach for climate change mitigation. Despite growing interest, a systematic review of this topic is still scarce. This study evaluated 1348 blue carbon sink-related articles from 1990 to 2020 using bibliometric technology. The results from total of 85 countries, 1538 institutions, and 4492 authors indicated that blue carbon sink research shows the characteristics of rapid growth. The most active country, institution, and author were USA, Chinese Academy of Sciences, and Duarte C.M., respectively. Relatively close academic collaboration has formed in blue carbon science. Environmental Sciences was the most popular category with 590 papers. The percentages of articles related to mangroves, saltmarshes, and seagrasses were 63.87%, 40.36%, and 40.65%, respectively. Mangrove carbon sinks are the most popular topic, and stable isotope and remote sensing are the most researched technologies for mapping and quantifying blue carbon sinks. The threats to blue carbon sinks are complex and distinctive. Restoration, conservation, and management of blue carbon ecosystems aimed to improve their carbon sink capacity are becoming hot issues and should be further investigated in the future. These findings provide a scientific roadmap for further research in this field and will enable stakeholders to identify the research trend.

An increase in population compels the textile industry to expand production to fulfill the apparel requirement, resulting in huge textile waste. These wastes are managed either by landfilling or incineration processes, which negatively contribute to the environment. Converting waste into value-added products is essential to reducing environmental pollution and thereby achieving a circular economy through proper waste management practices. This paper provides a comprehensive overview of different categories and forms of textile waste, their source of generation, the reusing capability of the textile industry, other valorization potentials in different fields, and various challenges associated with their valorization practices. This review presents textile wastes as the raw material source for preparing different value-added products such as in manufacturing textiles, packaging materials, plastics, composites, construction applications, energy generation, chemical additives, composting, and several other applications.

The global spread of COVID-19, international trade protectionism, geopolitical conflicts, and climate change presents challenges and risks to sustainable supply chains (SSCs). In recent years, scholarly interest in sustainable supply chain risk management (SSCRM) has continued to rise. A helpful literature review is necessary to enable supply chain practitioners to apply empirical findings from academic research or conceptual frameworks to their operations to maintain the stability and competitiveness of sustainable supply chains. The knowledge map of SSCRM is explored in this study using both quantitative and qualitative analysis. A total of 793 articles were retrieved to reveal the knowledge map of SSCRM. Scientometric and context analysis are combined in quantitative analysis to identify the intellectual structure of risk management research related to SSC. Then, a critical review is conducted in qualitative analysis to summarize and analyze the motivations, strategies, approaches, and tools of SSCRM. Combining the quantitative and qualitative analysis results, a conceptual model is constructed for SSCRM from three aspects: (1) risk identification, (2) risk assessment, and (3) risk mitigating and responding. Finally, future research directions are suggested based on the conceptual model for guiding the theories and practice of SSCRM. This study can work as a roadmap for providing appropriate risk management policies and toolkits to SSC, which could advance theoretical thinking on how to mitigate SSC risks.

Strategic emerging industries are key areas to transform the traditional industrial model of high pollution, high energy consumption, and high emissions. This paper focuses on the measurement of financing efficiency of strategic emerging industries. On the one hand, in order to overcome the interference of external environment and statistical error existing in the traditional single data envelope model, the SSBM-BOOT five-stage model is proposed. On the other hand, Malmquist index method and Luenberger productivity method are combined to evaluate dynamic efficiency, which select Beijing-Tianjin-Hebei listed companies’ data. The results show that (1) external environmental factors play a significant role in financing efficiency. The empirical results of the SSBM-BOOT five-stage model show that environmental factors “raise” the efficiency value of the whole Beijing-Tianjin-Hebei region. (2) Based on the revised data and the overall and decomposition results of SBM-ML index, it can be seen that the regional industry is still in the stage of scale expansion, and the financing efficiency depends on technological innovation that needs to be improved. Finally, the paper puts forward the concrete strategies of creating industrial development environment, promoting technological innovation, and establishing green investment and financing mechanism.

Desiccation cracking endangers the stability of expansive soils subjected to cyclic moisture variations. In the current research, prominent cracking prediction models including linear, linear elastic, linear elastoplastic, and linear elastic fracture were studied. Then, Monte Carlo limit state functions were generated based on predictions. Results indicate that there is less than 5% chance of cracking for depths beyond 0.5, 6, 8, and 9 m as predicted by the linear elastoplastic, linear elastic, linear, and linear elastic fracture models, respectively. Moreover, a series of sensitivity analysis was performed to evaluate model and parameter uncertainties. Comparatively, it was found that the linear model exhibits the highest uncertainty while linear elastoplastic model possesses the least uncertainty thus yielding a reasonable prediction. Additionally, soil parameters including matric suction followed by dry density were identified to govern the overall cracking. Using Bayesian inference, numerous conditional probabilities of variation of soil properties were investigated. Then, several cracking probabilities under history of low to high matric suction and dry density were obtained. Accordingly, Monte Carlo Markov decision chains were established based on several ecofriendly and feasible stabilization policies and their performance was also evaluated. The obtained safety factors (SF) suggest that stabilization plans resulting in high moisture and dry density have the least likelihood of cracking with a SF equal to 5.1. However, stabilization policies having low dry density and moisture yield have the least SF of 0.39. Findings of this study can improve the decision-making processes for expansive soil stabilization by considering a variety of environmental conditional probabilities.

The reinforcement strength characteristics of mechanically biologically treated (MBT) waste were studied by conducting consolidated undrained triaxial tests with MBT waste collected from the Hangzhou Tianziling landfill pilot project. In the tests, the effects of the reinforcement material used (geomembrane, geotextile, and geogrid) and the number of reinforcement layers used (one, two, and three layers) were assessed. The results showed the following: (1) even through the axial strain increases up to 25%, the deviator stress of MBT waste could not reach a well-defined peak; (2) the reinforcement effect is related to the type of reinforcement material, with geogrid exhibiting the best reinforcement effect and geomembrane the worst; (3) the strength ratio of reinforced MBT waste is related to the confining pressure and the number of reinforcement layers, with a greater strength ratio in the MBT waste attained with a lower confining pressure in a logarithmic relationship and a greater strength ratio in the MBT waste attained with a greater number of reinforcement layers in a linear relationship; (4) the reinforced MBT waste shear strength parameter variation ranges for the cohesion (c), internal friction angle (φ), effective cohesion (c′), and effective internal friction angle (φ′) are 3.92–13.69 kPa, 19°–29°, 10.10–27.94 kPa, and 24°–45°, respectively; and (5) the deviations in the test values from the apparent cohesion method and the semi-empirical formula method are less than 15%, indicating that these two theories of reinforced sand can also be applied to MBT waste. The results of this study are useful as a baseline reference for the stability assessment of MBT waste landfills.

One major factor, contributing to the emission of greenhouse gas in the environment, is generation of hazardous gases in municipal landfills. Due to these potential negative impacts, it is obligatory to estimate the amount and type of landfill gasses to design and build a gas collecting system. Landfill gas emissions are governed by the type of waste, its biodegradability, its methane emission potential, the degree of separation, and other miscellaneous factors. LandGEM model was used to predict the amount of gases produced in the landfills of Trichy (Ariyamangalam) and Thanjavur (Srinivasapuram). According to the results, the largest amount of landfill gas emissions would be in 1993 for Trichy (Ariyamangalam) landfill and in 2027 for Thanjavur (Srinivasapuram) landfill. The total amount of produced gas, methane, and carbon dioxide would be 16.2E + 10, 8.2E + 10, and 16.2 + 10 cubic meters per year in 1993 for Trichy and 13E + 6, 5E + 6 and 13E + 6 cubic meters per year in 2027 for Thanjavur.

Gene expression can be modified in people who are chronically exposed to high concentrations of heavy metals. The soil surrounding the Ventanas Industrial Complex, located on the coastal zone of Puchuncaví and Quintero townships (Chile), contain heavy metal concentrations (As, Cu, Pb, Zn, among others) that far exceed international standards. The aim of this study was to determine the potential association of the heavy metals in soils, especially arsenic, with the status of methylation of four tumor suppressor genes in permanent residents in those townships. To study the methylation status in genes p53, p16, APC, and RASSF1A, we took blood samples from adults living in areas near the industrial complex for at least 5 years and compared it to blood samples from adults living in areas with normal heavy metal concentrations of soils. Results indicated that inhabitants of an area with high levels of heavy metals in soil have a significantly higher proportion of methylation in the promoter region of the p53 tumor suppressor gene compared with control areas (p-value: 0.0035). This is the first study to consider associations between heavy metal exposure in humans and aberrant DNA methylation in Chile. Our results suggest more research to support consistent decision-making on processes of environmental remediation or prevention of exposure.

In this study, a combination of physical and chemical separation processes was used to recover the metallic components of red mud. At first, the impact of carbothermal reduction on magnetic separation of iron was studied. Low magnetic properties of iron minerals resulted in insignificant separation of iron from other components in the non-carbothermally reduced sample. Various carbothermal reduction parameters were optimized to maximize iron separation from other components. The optimum conditions were found T = 1350 °C, t = 120 min, coal/red mud ratio of 3, reaction time of 120 min, and the soda ash/red mud ratio of 0.2. Under the optimum condition, the iron recovery of the magnetic product was observed 91% with 81% Fe content, while the non-magnetic product has contained 90% of Ti and Al and 80% of rare earth elements (REEs). Following the physical separation of iron, the chemical separation of remaining red mud components was investigated using leaching with sulfuric, hydrochloric, and nitric acids. The leaching experiments were performed on two samples, treated red mud with carbothermal reduction and an untreated sample. The untreated sample had a higher dissolution efficiency for Ti and REEs than the carbothermally reduced sample. Different dissolution behavior of the red mud components was explained by samples’ mineralogy. In the end, considering the obtained results, various scenarios for the recovery of red mud components were evaluated from technical and environmental aspects.

We engineered a tiger nut residue (TNR, a low-cost agricultural waste material) through a facile and simple process to take advantage of the introduced functional groups (cetylpyridinium chloride, CPC) in the removal of 2,4-dichlorophenoxyacetic acid (2,4-D) in batch mode and further investigated its impingement on bacterial growth in a yeast-dextrose broth. The surface characterizations of the adsorbent were achieved through Fourier-transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller method (BET), X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS). The batch adsorption studies revealed that solution pH, adsorbent dose, temperature, and salt affected the adsorptive capacity of TNR-CPC. The equilibrium data were best fitted by Langmuir isotherm model with a maximum monolayer adsorption capacity of 90.2 mg g–¹ at 318 K and pH 3. Pseudo-second-order model best fitted the kinetics data for the adsorption process. Physisorption largely mediated the adsorption system with spontaneity and a shift in entropy of the aqueous solid-solute interface reflecting decreased randomness with an exothermic character. TNR-CPC demonstrated a good reusability potential making it highly economical and compares well with other adsorbents for decontamination of 2,4-D. The adsorption of 2,4-D proceeded through a probable trio-mechanism; electrostatic attraction between the carboxylate anion of 2,4-D and the pyridinium cation of TNR-CPC, hydrogen bonding between the hydroxyl (–OH) group inherent in the TNR and the carboxyl groups in 2,4-D and a triggered π-π stacking between the benzene structures in the adsorbate and the adsorbent. TNR-CPC reported about 99% inhibition rate against both gram-positive S. aureus and gram-negative E. coli. It would be appropriate to investigate the potential of TNR-CPC as a potential replacement to the metal oxides used in wastewater treatment for antibacterial capabilities, and its effects against airborne bacteria could also be of interest.