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The present study was conducted in order to investigate the efficiency of different advanced oxidation processes both individually and in combination with the biological method for the removal of color and chemical oxygen demand (COD) from wastewater in the pulp and paper industry. Advanced oxidation processes include ozone, Fenton, hydrogen peroxide, and photo-Fenton. Biologically treated wastewater was successively subjected to advanced oxidation processes (AOPs). The optimum conditions for the ozone treatment of raw wastewater were found to be a contact time of 9 min and a pH of 5 at a fixed dose of ozone for a removal efficiency of 41.22% for color and 88.53% for COD. Similar optimum conditions for the ozone treatment of biologically treated wastewater showed a removal efficiency of 46.36% for color and 95.92% for COD. The photo-Fenton process also showed an efficiency comparable to the ozone treatment for both raw wastewater and biologically treated wastewater, resulting in a removal efficiency of 39.85% (color) and 90.13% (COD) for raw wastewater, and of 41.34% (color) and 94.29% (COD) for biologically treated wastewater. Each had a contact time of 12 h. The Fenton oxidation of raw wastewater showed a removal efficiency of more than 26.30% for color and 86.33% for COD. Fenton oxidation, however, showed an efficiency of 26.62% for color and 84.49% for COD removal from biologically treated wastewater. Hydrogen peroxide showed an efficiency of 28.45% for color and 85.13% for COD removal from raw wastewater, and 39.48% for color and 86.53% for COD removal from biologically treated wastewater. The results for the raw wastewater treatments indicated that higher removal efficiencies can be achieved when they are used as pre-treatments. Biological treatment is a cost-effective method but it has less efficiency for color removal. In combination with one of the AOPs, either as a pre- or post-treatment under a controlled time and dose, biological treatment increased the efficiency, making treatment feasible at larger scales. [ABSTRACT FROM AUTHOR]

With the increasingly strict supervision of the ecological environment and the continuous improvement of pollution control requirements, there are many options for water pollution control technology in the pulp and paper industry. How to choose reasonable and effective control technology has become the focus of attention. In this paper, a water pollution control technology evaluation model based on the Pythagorean language neutrosophic set (PLNS) is proposed for the first time. Firstly, the concept of PLNS is defined and its characteristics are discussed. Then the score function and accuracy function of the Pythagorean language neutral number (PLNN) are defined. To apply PLNNs to multi-attribute decision-making, PLNN power-weighted geometric operator (PLNNPWG) and PLNNPWG geometric Heronian mean operator (PLNNPWG-GHM) are proposed and a multi-attribute decision-making method is proposed. Finally, this method is used to evaluate the water pollution control technology of the pulp and paper industry. Through the experimental results, it can be seen that if the comprehensive weights are used, elemental chlorine-free (ECF) clean bleaching technology is the best choice, when using single weights to calculate, in technical characteristics, ECF clean bleaching performed best. In economic cost, chlorination, enhanced alkali treatment, hypochlorite (CEH) three-stage bleaching performed best. In operation management and environmental impact, ECF clean bleaching and total chlorine-free (TCF) clean bleaching had almost the same score. This model can provide a reliable basis for enterprises to choose the appropriate water pollution control technology and also provide strong support for the management department to recommend the best feasible technology. [Display omitted] • Propose the Pythagorean language neutrosophic set (PLNS). • Define the score function and accuracy function of Pythagorean language neutral number (PLNN). • Propose the PLNN power-weighted geometric (PLNNPWG) and PLNNPWG geometric Heronian mean (PLNNPWG-GHM) operators. • Propose a decision-making method to evaluate the water pollution control technology of pulp and paper industry. • Provide strong support for the management department to recommend the best feasible technology. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the integration of urban habitat data in spatial development documents across Poland's 28 largest cities and assessed the implications for urban environmental management and biodiversity conservation. The detailed habitat maps identify critical areas for protection, enhancing ecosystem services, and supporting nature-based solutions that positively impact residents' health and social cohesion. A total of 372 sources were analyzed and 467 habitat types were identified primarily from phytosociological surveys. However, only 33.2% of these habitats have been included in urban planning documents, highlighting a substantial integration gap. Complete taxa lists and habitat maps covering the entire city area, suitable for biodiversity management needs, are rarely included in urban planning documents. The findings have underscored the need for detailed habitat mapping to improve urban environmental management, biodiversity conservation, and public health promotion. [ABSTRACT FROM AUTHOR]

The present study was conducted in order to investigate the efficiency of different advanced oxidation processes both individually and in combination with the biological method for the removal of color and chemical oxygen demand (COD) from wastewater in the pulp and paper industry. Advanced oxidation processes include ozone, Fenton, hydrogen peroxide, and photo-Fenton. Biologically treated wastewater was successively subjected to advanced oxidation processes (AOPs). The optimum conditions for the ozone treatment of raw wastewater were found to be a contact time of 9 min and a pH of 5 at a fixed dose of ozone for a removal efficiency of 41.22% for color and 88.53% for COD. Similar optimum conditions for the ozone treatment of biologically treated wastewater showed a removal efficiency of 46.36% for color and 95.92% for COD. The photo-Fenton process also showed an efficiency comparable to the ozone treatment for both raw wastewater and biologically treated wastewater, resulting in a removal efficiency of 39.85% (color) and 90.13% (COD) for raw wastewater, and of 41.34% (color) and 94.29% (COD) for biologically treated wastewater. Each had a contact time of 12 h. The Fenton oxidation of raw wastewater showed a removal efficiency of more than 26.30% for color and 86.33% for COD. Fenton oxidation, however, showed an efficiency of 26.62% for color and 84.49% for COD removal from biologically treated wastewater. Hydrogen peroxide showed an efficiency of 28.45% for color and 85.13% for COD removal from raw wastewater, and 39.48% for color and 86.53% for COD removal from biologically treated wastewater. The results for the raw wastewater treatments indicated that higher removal efficiencies can be achieved when they are used as pre-treatments. Biological treatment is a cost-effective method but it has less efficiency for color removal. In combination with one of the AOPs, either as a pre- or post-treatment under a controlled time and dose, biological treatment increased the efficiency, making treatment feasible at larger scales.

This paper studies the impact of digital economy development on carbon emissions, which is a hot topic in the field of environmental economics. This topic is within the scope of the Frontiers in Environmental Science and is particularly in line with the theme of Environmental Economics and Management section in the journal. Firstly, this paper constructs the Digital Economy Development Index and its variable indicators to measure the development of the digital economy. Secondly, this paper uses urban panel data to reveal the impact of digital economy development on carbon emissions, and further adopts IV method to deal with endogeneity issues. Thirdly, this paper performs the heterogeneity analyses depending on the characteristics of the city. The results can provide a basis for formulating differentiated policies. Fourthly, this paper further explores the mechanism by which the digital economy affects carbon peaking. The results show that the digital economy may influence carbon peaking through upgrading of the industrial structure, technical innovation, and energy consumption. [ABSTRACT FROM AUTHOR]

The Spanish National Advisory Board of Mariculture (JACUMAR) developed an initiative to unify methodologies between the regions of Spain, in which they proposed the implementation of site-specific “Environmental Monitoring Plans” (EMPs). In this study, we tested the feasibility of an EMP on a fish farm in the Mediterranean Sea. The methods and tools proposed in the EMP are highly useful for environmental monitoring of aquaculture. However, spatial heterogeneity figured prominently in a univariate analysis with environmental variables and a multivariate analysis of polychaete assemblages. This variability may be due to habitat patchiness, and may therefore be solved by an improved experimental design, e.g. by adding replications for increasing statistical power. Multivariate analysis of polychaete assemblages provided accurate information about the quality of the sediment. This information could also be improved using ecological data about key polychaete families in order to avoid misleading results. Thus, the JACUMAR EMP has proved useful in providing precise information about the ecological status of marine benthic habitats, meeting the requirements of current European Directives. However, we suggest that some modifications may be required in order to account for possible misleading thresholds for environmental quality standards, spatial heterogeneity and increasing power analyses.