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Corporate governance, environmental sustainability performance, and normative isomorphic force of national culture Texte intégral
2022
Peng, Xuhui | Zhang, Ruru
With the increasing concern regarding climate change, academics and practitioners are devoting attention to corporate environmental sustainability development. However, corporate environmental responsibility as an outcome of corporate governance (CG) practice is also constrained by national culture as an institutional factor, and research on the relationship between CG and environmental sustainability performance (ESP) with consideration for national culture remains scarce. Therefore, this study investigates the ESP data of Forbes’ listed multinational corporations (MNCs) through content analysis and applies STATA software with stepwise regression models to empirically test the relationship between CG and MNCs’ ESP and the moderating effects of national culture on this relationship. The results show that board independence and board size positively affect MNCs’ ESP, and the relationship between board independence and MNCs’ ESP is negatively moderated by masculinity and uncertainty avoidance. Our results emphasize the importance of CG in environmental decision-making by board management supervision enhancement and explain how national culture affects ESP because of its influence on CG. Our study explains the agency effect of board composition on MNCs’ environmental sustainability development and the influence of national culture, which establishes a link between CG, ESP, and national culture. Moreover, policymakers and MNCs’ suggestions for enhancing ESP through CG measures, while considering national culture, are also provided.
Afficher plus [+] Moins [-]Multifactor effects on the N2O emissions and yield of potato fields based on the DNDC model Texte intégral
2022
Wang, Liwei | Zhang, Kai | Guo, Kangjun | Liu, Limin | Zhang, Tao | Xu, Mingjie | Yan, Xuefei | Gao, Xining
Maintaining or increasing grain yields while also reducing the emissions of field agricultural greenhouse gases is an important objective. To explore the multifactor effects of nitrogen fertilizer on nitrous oxide (N₂O) emissions and the yield of potato fields and to verify the applicability of the denitrification–decomposition (DNDC) model when used to project the N₂O emission load and yield, this research chooses a potato field in Shenyang northeast China from 2017 to 2019 as the experiment site. The experiment includes four nitrogen levels observing the emission of N₂O by static chamber/gas chromatograph techniques. The results of this study are as follows: (1) DNDC has a good performance regarding the projection of N₂O emissions and yields. The model efficiency index EFs were 0.45 ~ 0.88 for N₂O emissions and 0.91, 0.85, and 0.85 for yields from 2017 to 2019. (2) The annual precipitation, soil organic carbon, and soil bulk density had the most significant influence on the accumulated N₂O emissions during the growth period of potatoes. The annual precipitation, annual average temperature, and CO₂ mass concentration had the most significant influences on yield. (3) Under the premise of a normal water supply, sowing potatoes within 5 days after the 5-day sliding average temperature in this area exceeds 10℃ can ensure the temperature required for the normal growth of potatoes and achieve the purpose of maintaining and increasing yield. (4) The application of 94.5 kg·hm⁻² nitrogen and 15 mm irrigation represented the best results for reducing N₂O emissions while also maintaining the yield in potato fields.
Afficher plus [+] Moins [-]Analysis of core risk factors and potential policy options for sustainable supply chain: an MCDM analysis of Saudi Arabia’s manufacturing industry Texte intégral
2022
Alshehri, Sultan Mohammed A | Jun, Wang Xue | Shah, Syed Ahsan Ali | Solangi, Yasir Ahmed
Sustainable supply chain management (SSCM) has been a tough challenge for developing economies like Saudi Arabia. Implementation of SSCM practices in the manufacturing industry has been prone to multiple risk factors that need to be identified, evaluated, and prioritized especially considering the dynamics of the manufacturing industry in a developing economy. Moreover, it is also imperative to trace out feasible and sustainable strategies to overcome the risks to SSCM practices adoption. This study serves this purpose and identifies, evaluates, prioritizes the risk factors, sub-factors, and strategies to overcome these risk factors in the implementation of SSCM practices in the manufacturing industry in Saudi Arabia. An integrated multi-criteria decision analysis approach by combining fuzzy AHP and fuzzy WASPAS methods is employed for the analyses. The fuzzy AHP analysis results show that economic risks are dominant risks followed by the managerial policy risks and environmental risks in implementing SSCM. Industrial emissions are the leading risk factors in the overall ranking of the sustainable supply chain sub-risk factors followed by market dynamics, management policy failures, financial constraints, and credit uncertainty. While evaluating the sustainable supply chain strategies using fuzzy WASPAS, it is concluded that commitment and support of top, middle, and lower level management is the most pivotal strategy to deal with the risks to SSCM in Saudi Arabia followed by establishing environmental policies and goals to adopt SSCM, and provision of the financial resources and subsidies.
Afficher plus [+] Moins [-]The association between phenanthrene and nutrients uptake in lotus cultivar 'Zhongguo Hong Beijing' Texte intégral
2022
Wang, Xiaowen | Wang, Yanjie | Zhao, Xiaoyan | Chen, Bingqiong | Kong, Nannan | Shangguan, Lingfei | Zhang, Xiaobin | Xu, Yingchun | Hu, Feng
It has been well documented that polycyclic aromatic hydrocarbon (PAHs) can be taken up from the environment by the plants and translocated into the shoots. However, the mechanisms underlying this process are poorly understood. Nelumbo nucifera L. (lotus) is a highly ornamental aquatic plant known to possess strong phytoremediation capability. In the present study, the association between phenanthrene (Phe) and nutrients, including nitrogen (N) and phosphorus (P), in lotus was investigated. Over 2 years, all eight lotus cultivars tested accumulated Phe to various degrees when grown in PAH-polluted sediment (0.46 mg/kg Phe). Cluster analysis showed N. nucifera 'Zhongguo Hong Beijing (ZHB)' was the one with the highest Phe levels in the leaves and petals in 2 years. The Phe concentrations in the tissues of 'ZHB' were 3.14 mg/kg and 1.63 mg/kg on average in the first and second year, respectively. Interestingly, 'ZHB' was also the cultivar with the lowest N and P levels considering 2 years and tissues. Hydroponic studies further revealed a negative association between the concentrations of Phe and those of N and P in the aerial tissues under 0.5 and 1.0 mg/L Phe treatments in 'ZHB'. Furthermore, the significant reductions of the roots number (72.6%), longest root length (75.8%), and petiolar height (34.6%) in 'ZHB' seedlings exposed to 1.0 mg/L Phe were observed, indicating that Phe retarded the growth of lotus. These results provide a new understanding of the accumulation of Phe in plants and the association with nutrients and enrich the basis of phytoremediation to the contaminated environment.
Afficher plus [+] Moins [-]An integrated framework for exploring the tradeoffs between cost-optimized fuel allocation and regional air quality impacts in a water-energy nexus infrastructure Texte intégral
2022
Alhajeri, Nawaf S. | Al-Fadhli, Fahad M. | Alshawaf, Mohammad | Aly, Ahmed
This paper presents an integrated framework in which an air quality dispersion model is combined with an economic dispatch model to address the environmental tradeoffs of a cost-optimized fuel allocation strategy. A unit commitment dispatch model was developed to re-allocate fuel between power generation and desalination plants. Then, an air quality dispersion model was run for a 1-year period to simulate the spatiotemporal transport of pollutants and the possible formation of air pollution hotspots. The results showed that optimizing fuel allocation can reduce the associated fuel cost by as much as 16.5% of the total cost (1.08 billion USD). The optimized fuel allocation approach resulted in reducing the base case emissions of NOx, SO₂, CO, and PM₁₀ by 25%, 4.6%, 3.1%, and 7.6%, respectively. However, the air quality impact of the optimized fuel allocation scheme was not as favorable. The 1-h-averaged maximum concentration of SO₂ increased, and NOx concentrations were slightly above the allowable limits. Although fewer pollutants were emitted over the study period in the optimized fuel allocation case, the variability in how fuel was allocated between power and desalination plants concentrated emissions near residential areas. As a result of this trend, the maximum 1-h concentrations of all pollutants increased, with increases ranging from 1% for CO to 29% for PM₁₀. In addition, the total number of hourly SO₂ concentration violations increased dramatically, leading to additional hotspot areas. Therefore, the effectiveness of any environmental-economic fuel dispatch strategy should be tested based on additional indicators such as the allowable limits of pollutant concentrations and not exclusively the overall emissions of the system. This approach could promote the selection of the most economic fuel dispatch method while simultaneously considering regional air quality impacts.
Afficher plus [+] Moins [-]Nutrient and tetracycline removal from simulated biogas slurry and biogas upgrading by microalgae cultivation under different carbon nanotubes concentrations Texte intégral
2022
Sun, Li | Zhao, Chunzhi | Sun, Shiqing | Hu, Changwei | Zhao, Yongjun | Liu, Juan
The present study sought to determine the effects of multi-walled carbon nanotubes (MWCNTs) concentrations (0–10 mg L⁻¹) on tetracycline (TC) and biogas slurry nutrient removal by microalga Chlorella vulgaris cultivation. Treatments with 1 mg L⁻¹ MWCNTs yielded the maximum chlorophyll a content, dry weight, and algal density of 143.73 ± 3.11 μg L⁻¹, 0.81 ± 0.008 g L⁻¹, and 5.83×10⁷ cells L⁻¹, respectively, suggesting that 1 mg L⁻¹ MWCNTs could enhance microalgal growth performance and photosynthesis effectively. The highest removal rates of chemical oxygen demand, total phosphorus, total nitrogen, TC, and CO₂ under 1 mg L⁻¹ MWCNTs were 90.43 ± 5.15%, 78.12 ± 4.33%, 77.07 ± 4.12%, 89.64 ± 3.08%, and 64.26 ± 0.71%, respectively. These results elucidated that moderate MWCNTs concentrations might promote TC and nutrient removal by enhancing Chlorella vulgaris photosynthesis activity.
Afficher plus [+] Moins [-]Greenhouse gas emissions of biosolid and cow manure during composting and vermicomposting and when applied to soil cultivated with wheat (Triticum sp. L.) Texte intégral
2022
Miranda-Carrazco, Alejandra | Ramírez-Villanueva, Daniel Alejandro | Dendooven, Luc
Biosolids are a by-product of wastewater treatment, and their nutritional composition makes them ideal for fertilizing crops. However, pre-treatments, such as conditioning and/or (vermi)composting, are often required to stabilize the product and remove pathogens. Biosolids, cow manure, and a 50–50% mixture were conditioned for 21 days, composted or vermicomposted with Eisenia fetida (Savigny 1826) for 28 days, and applied to soil cultivated with wheat (Triticum sp. L.), while emissions of nitrous oxide (N₂O), methane (CH₄), and carbon dioxide (CO₂) were monitored. Emissions of CH₄ were large from the biosolid and N₂O from the cow manure during conditioning. Emissions of CH₄ remained high during (vermi)composting of the biosolids, while the emissions of N₂O from the cow manure dropped. The addition of E. fetida did not affect the emissions of greenhouse gases during (vermi)composting. The emission of N₂O was higher when (vermi)composted biosolid was applied to soil cultivated with wheat than when (vermi)composted cow manure was applied. The global warming potential (GWP) of the sum of the emitted greenhouse gases (GHG) during conditioning, (vermi)composting, and when the final product was applied to soil was 3 times larger from the cow manure than from the biosolid, but mixing biosolid with cow manure eliminated that difference. It was concluded that mixing biosolid with cow manure might be a simple way to reduce the GWP of the emitted GHG during storage, (vermi)composting, and when applied to soil.
Afficher plus [+] Moins [-]Mechanical property and microstructure of cemented tailings backfill containing fly ash activated by calcium formate Texte intégral
2022
Wang, Yiming | Wu, Jiangyu | Bu, Hai | Yin, Qian | Jing, Hongwen
Cemented tailings backfill (CTB) is the most economical and environmental method to recycle tailings and fly ash (FA) for filling mining, but the high content of FA will weaken its strength property. This paper aims to use calcium formate (CF) as an activator to stimulate the activity of FA, thereby enhancing the mechanical property of CTB. The influence of FA and CF content on the stress-strain behavior, dilatancy deformation, and compressive strength of CTB was investigated using uniaxial compression test and scanning electron microscope. The coupling effect mechanism of FA and CF content on the compressive strength of CTB was revealed. The results show that increasing the content of FA and CF can enhance the bearing capacity of CTB during the dilatancy deformation stage, but the excessive content of FA and CF will lead to the attenuation of peak stress. The relations between FA content, CF content, and the compressive strength of CTB can be characterized by quadratic polynomial. Adding CF can stimulate the activity of insoluble FA, increasing the utilization of FA in CTB and producing rich hydration products to fill the internal defects of CTB. The microstructure of CTB is effectively improved by adding CF, including the size and distribution of microcracks and micropores, so that the strength property of CTB is optimized. However, too much CF will make the microstructure of CTB loose and porous, resulting in more microcracks and micropores. Microcracks propagate and connect with micropores to form defects, which deteriorate the microstructure of CTB, thus weakening the strength parameters of CTB. This study provides a method to increase the utilization of FA in CTB, which is of great significance for strengthening the mechanical properties of CTB and improving engineering economic benefits.
Afficher plus [+] Moins [-]Asbestos cement waste treatment through mechanochemical process with KH2PO4 for its utilization in soil pH correction and nutrient delivery Texte intégral
2022
Borges, Roger | Giroto, Amanda S. | Guimarães, Gelton G. F. | Reis, Heitor P. G. | Farinas, Cristiane S. | Ribeiro, Caue
The manufacture of asbestos materials has been banished worldwide due to their toxicity, but discarding the existing wastes remains a challenge. We investigated an alternative mechanochemical method to treat asbestos-cement materials by loading them with potassium and phosphorus from KH₂PO₄ during the milling process to obtain a product used as liming and soil conditioner. The results showed total asbestos fibrous elimination after 7 to 8 h of milling. The materials showed a slow-release fertilizer profile. The liming property is maintained when the asbestos-cement weight proportion used is equal to or higher than KH₂PO₄. A comparative soil experiment with limestone also indicates that lower doses of the K- and P-enriched detoxified asbestos cement were required to reach similar liming effects. Maize cultivation (greenhouse) was used to evaluate its performance showing higher biomass production for the sample loaded with potassium and phosphorous.
Afficher plus [+] Moins [-]Tracking the effect of climatic and non-climatic elements on rice production in Pakistan using the ARDL approach Texte intégral
2022
Gul, Amber | Xiumin, Wu | Chandio, Abbas Ali | Rehman, Abdul | Siyal, Sajid Ali | Asare, Isaac
The present study aims to investigate the effect of climatic and non-climatic factors on rice production by employing an annual time series data from the period of 1970 to 2018. The study employed an ARDL (Autoregressive Distributed Lag) approach, and the long-term equilibrium linkages between the variables have been discovered. Additionally, the study also used a regression model to determine the robustness for the authentication of results. The Fully Modified Ordinary Least Squares (FMOLS), Canonical Cointegration Regression (CCR) methods, and the VECM (Vector Error Correction Model) technique confirmed the long-run causal relationships amid the variables. The empirical results further revealed that climatic factors including annual temperature negatively affect the rice crop production, while carbon dioxide emission positively influenced via long-run. Similarly, non-climatic factors like area under rice crop, fertilizer consumption, labor force, and water availability affect the rice production positively in the long-run analysis. Finally, the pairwise Granger causality test revealed that both climatic and non-climatic variables had a substantial impact on rice yield in Pakistan. Based on the study’s findings, the government and policy makers should formulate alleviation polices to tackle with harsh effects of climate change and consistent adoption of measures to secure overall agricultural production including rice crop because it is a country stable food.
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