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The driving forces of energy-related carbon dioxide emissions from South Latin American countries and their impacts on these countries’ process of decoupling Texto completo
2020
Moutinho, Victor | Santiago, Renato | Fuinhas, Jose Alberto | Marques, António Cardoso
An extensive decomposition analysis was used to research the primary driving forces behind energy-related carbon dioxide emissions per capita for the period 1993 to 2017 in a panel of South American countries. Evidence was found that the effect of per capita renewable productivity was challenging and compromised in South Latin American countries. Decoupling changed from a weak state to a strong decoupling state after the Kyoto protocol. When we remove the renewable productivity per capita effect, the results show that the state of strong decoupling was mainly achieved due to a group of economic drivers, with the negative changes in energy intensity, and in the gross domestic investment, proving to be the most significant contributors to decreasing CO₂ emission per capita.
Mostrar más [+] Menos [-]Decoupling of environmental pressure and economic growth: evidence from high-income and nuclear-dependent countries Texto completo
2020
This paper proposes a three-step process, based on the definition of absolute decoupling (AbsDec), to analyze the role of nuclear energy in the absolute decoupling between environmental pressures (including Energy resource use and CO₂Emissions) and Economic growth (3-E) during the period 1987–2016. First, we select the top four Nuclear-Dependent Countries (4-NDC), including France, Belgium, Sweden, and Switzerland, from high-income economies and the USA as a sample (i.e., 5-country). Second, we provide compound annual growth rate (CAGR) statistics for all relevant variables in each country. Third, we assess the Carbon Kuznets Curve (CKC) and investigate the dynamic interactions between 3-E by using Lotka–Volterra ecosystem model. For the 5-country, we find that the CAGR of GDP is positive, the CAGRs of CO₂ emissions, CO₂ intensity, and energy intensity are negative, the panel CKC exists, and the projected CAGRs of CO₂ emissions are negative between 2017 and 2025. For the USA, a commensalism of energy-led growth and an amensalism of emissions-limited growth exist. For the 4-NDC, neutralisms between 3-E exist. The aggregated results indicate that the 4-NDC seem to have achieved an AbsDec between 3-E, the USA appears to achieve an AbsDec between economic growth and emissions while undergoing a relative, and perhaps absolute, decoupling between 3-E. The findings can infer that nuclear power is one of the most important energy sources for achieving absolute decoupling and genuinely sustainable development. The policy implication is that measures to reduce energy consumption and control CO₂ emissions may not significantly impair economic growth in countries that rely on nuclear power.
Mostrar más [+] Menos [-]Estimation of chlorophyll-a Concentration of lakes based on SVM algorithm and Landsat 8 OLI images Texto completo
2020
Chlorophyll-a (Chl-a) is the main component of phytoplankton and an important index of water quality. Pearson correlation analysis is conducted on measured Chl-a concentration and band reflectance to determine the sensitive bands or multiband combinations of the Chl-a to input to a support vector machine (SVM) model. An indicator β is defined to evaluate the model performance of fitting and prediction. The model performs well with the lowest β (decision coefficient, (R²) = 0.774; root mean square error (RMSE) = 22.636 μg/L) of the validation set. The model test results prove that the model performs well. We analyze the impact factors of the model. The seasonal factor affects the model performance significantly; thus, samples from different seasons should be combined to train the model and inverse the water quality. Noise points reduce the model accuracy significantly; therefore, obvious outliers must be excluded at first. Additionally, the sampling method affects model accuracy, and systematic sampling in the descending order of Chl-a concentration is recommended. The combination of SVM algorithm and remote sensing technology provides a convenient, scientific, and real-time method to monitor and control water quality.
Mostrar más [+] Menos [-]A comprehensive analysis of e-waste legislation worldwide Texto completo
2020
The improper disposal and informal processing of e-waste have raised serious concerns for the environment and human health worldwide. A variety of legislative frameworks have been implemented to regulate e-waste management and upcycling in order to prevent environmental pollution and adopt resource reuse. Current e-waste legislation in different countries mostly include restrictions on e-waste import/export, regulations for recycling specific categories of e-waste, and Extended Producer Responsibility (EPR). This article serves as a comprehensive commentary to weigh the advantages and drawbacks of the different e-waste legislation enforced around the world. Though each country’s e-waste legislation is enframed to address the country-specific problems, the legislation is mostly not holistic, leading to different management issues. A variety of e-waste management issues prevalent in most countries (with e-waste specific legislation) have been listed and categorized for better understanding of the status quo. Further, the article proposes a generic e-waste management model catering to requirements of countries around the world. The implementation of such a model for Europe, China, India, Japan, South Korea, Taiwan, and Australia has been illustrated to show that the model can suit both developed and developing countries with contrasting e-waste management issues. The challenges that would arise in implementing an effective legislation and mechanisms for overcoming these challenges have also been discussed. To conclude, the role of governing bodies in tackling the future e-waste problems has been highlighted. In total, the article promotes scaling up the feasibility and efficacy of the implementation of e-waste policies across the globe in the coming years.
Mostrar más [+] Menos [-]The influences of openness on China’s industrial CO2 intensity Texto completo
2020
As a main cause of global warming, carbon emissions have received growing concerns of Chinese government. As the main sources of carbon emissions, industrial sectors account for approximately 70% of China’s total emissions. In this study, the effect of openness involving foreign direct investment, together with import and export on the industrial CO₂ intensity, is comprehensively analyzed from the technology spillover perspective. Employing a panel dataset of 34 industrial sectors for the period of 2000–2010, linear regression analysis by fixed effects, the feasible generalized least squares estimator, and the Driscoll–Kraay estimator are employed. The estimation results indicate that the openness is conducive to low-carbon development except export. A further investigation conducted by employing the panel threshold model suggests that the influences of openness on the industrial CO₂ intensity are dependent on the specific characteristics of the industrial sectors, such as the domestic innovation and the level of foreign investment entering in China’s industrial sectors. These findings allow the relevant policy makers to carry out insightful policies aimed at pursuing low-CO₂ intensity by considering the characteristics and situations of the local absorptive ability.
Mostrar más [+] Menos [-]Monitoring the effects of open-pit mining on the eco-environment using a moving window-based remote sensing ecological index Texto completo
2020
Environmental problems caused by mines have been increasing. As one of the most serious types of mining damage caused to the eco-environment, open pits have been the focus of monitoring and management. Previous studies have obtained effective results when evaluating the ecological quality of a mining area by using the remote sensing ecological index (RSEI). However, the calculation of RSEI does not consider that the ecological environmental impact is limited under natural conditions. To overcome this shortcoming, this paper proposes an improved RSEI based on a moving window model, namely the moving window-based remote sensing ecological index (MW-RSEI). This improved index is more in agreement with the First Law of Geography than RSEI. This study uses Landsat ETM/OLI/TIRS images to extract MW-RSEI information of a case area in Zhengzhou City, Henan Province, central China, in 2009 and 2018. The results revealed that the average value of MW-RSEI declined from 0.668 to 0.611 from 2009 to 2018, and the main drivers of the deterioration of the eco-environment were land use/cover (LUCC) changes, most of which were derived from urban expansion and mining. The serious impact of open pits on the eco-environment in mining areas is mainly due to their low vegetation cover; therefore, some effectively managed open pits can have a positive impact on the mining environment. The use of MW-RSEI provides valuable information on the eco-environment surrounding the open pit, which can be used for the rapid and effective monitoring of the eco-environment in mining areas.
Mostrar más [+] Menos [-]Nitrous oxide gas emissions estimated by liquid-phase measurements: robustness and financial opportunity in single and multi-point monitoring campaigns Texto completo
2020
Fenu, Alessio | Wambecq, Tom | de Gussem, Kris | Weemaes, Marjoleine
A liquid-phase nitrous oxide sensor can be used as a proxy to estimate the gas emissions. Experiments conducted in a pilot-scale Anammox reactor, at different degrees of aeration intermittency, indicate a predictive error in the range of 13.4–19.3% during the stripping phase, with a higher error range in the unaerated phases (23.4–62.8%). The total emissions not explained by the aerated model amounted to 14.1%. Only a negligible fraction (3.6%) of the total nitrous oxide emissions were not captured by the unaerated phase model, indicating thus a minor concern for full-scale application. A sensitivity analysis performed on the present study indicates that the quality of the nitrous oxide measurement is of extreme importance to decrease the load prediction uncertainty. Air flow measurement errors have lower impact on the overall load prediction. The financial attractivity of this monitoring approach is significant in completely mixed tank reactors. In presence of a multi-point analysis, and starting from two monitoring points, the financial interest deteriorates by the relatively short lifetime of the commercially available liquid-phase nitrous oxide sensor.
Mostrar más [+] Menos [-]Potential use of morphological deformities in Chironomus (Diptera: Chironomidae) as a bioindicator of heavy metals pollution in North-East Algeria Texto completo
2020
Human activities have led to profound changes in aquatic environments and degradation at several levels. Preserving the quality of aquatic environments, their good functioning, and the species that are dependent on them has become a crucial element. In order to monitor the overall health of aquatic ecosystems, it is necessary to develop early indicators of environmental quality. In this work, we have tried to evaluate whether the analysis of morphological deformities affecting Chironomidae larvae could tell us about the state of degradation of water courses that are subjected to different discharges. To do this, water, sediment, and larvae of Chironomidae were sampled in dry weather in August–September of 2017 at three sites located in the North-East of Algeria. The heavy metals in the three compartments as well as the deformities affecting the mentum and mandibles of Chironomus were analyzed. The results showed a metal contamination especially in sediments; the highest values were found in Meboujda River and Seybouse River. The three sites have high deformities incidences, more than 33%, which suggests the presence of toxic stress. This study reflected the relationship between heavy metal concentrations in water, sediments, and deformities larval mouthparts (mentum and mandibles) in Chironomus. The use of deformities in Chironomus sp. can serve as an effective tool for bioassessment of freshwater ecosystems.
Mostrar más [+] Menos [-]Adverse effects of oxo-degradable plastic leachates in freshwater environment Texto completo
2020
The production of biodegradable plastics is considered to be a way to reduce plastic waste issue. Among others, oxo-degradant additives enable a faster degradation of plastics in the environment. However, the introduction of these new materials could provoke the release of substances potentially toxic in the environment. This work determined and compared the toxicity of leachates from various additivated polymers (polyethylene, PE; polypropylene, PP; polystyrene, PS) upon different test organisms: plants (Sorghum saccharatum, Lepidium sativum, Sinapis alba, and Vicia faba), crustacean (Daphnia magna), and luminescent bacteria (Vibrio fischeri). Daphnia magna survival was mainly affected by PS and PP leachates (72% and 61% effect, respectively) while PS notably reduced the reproduction rate. On plants, only PP exerted a negative effect (S. saccharatum IG% 32.4), while V. fischeri always showed values around 50%. The data integration, through the Toxicity Test Battery Integrated Index (TBI) approach, allowed to rank the leachates toxicity as PE > PS > PP. This result could be mainly ascribable to the highest metals content in PE since no difference with organic compounds analysis was evidenced. In conclusion, since the polymers exerted dissimilar toxicity, the additive could not be considered the sole responsible of the measured toxicity, but its role in the enhancement of the virgin polymers leachates effects can be solidly hypothesized.
Mostrar más [+] Menos [-]Identification of critical factors in construction and demolition waste recycling by the grey-DEMATEL approach: a Chinese perspective Texto completo
2020
The extensive waste produced in construction and demolition activities affects the ecological environment, impeding green development in countries worldwide, including China. China has paid increasing attention to managing construction and demolition waste (CDW). However, most of the existing research only qualitatively studies the factors affecting the recycling of CDW and does not reveal the critical factors. Therefore, based on stakeholder theory and the grey-DEMATEL method, this paper aims to identify and quantitatively analyze the critical factors in CDW recycling from the perspective of China. This paper drew the following conclusions: (1) Stakeholders in China’s CDW recycling mainly include the government, CDW production units, and CDW recycling units. (2) Public policy, government subsidies, media promotion, human resources, cost, environmental awareness, technological innovation, and supply chain management are the eight dimensions with 13 factors that constitute CDW recycling in China. (3) For the total relations between factors affecting the recycling of CDW in China, the most influential factor is specific legislation and regulations. The factor with the highest degree of prominence is environmental awareness. The factor with the largest net cause value is the rationality of disposal and landfill charges. The factor with the largest net effect value is experienced construction workers. (4) The critical factors in China’s CDW recycling include specific legislation and regulations, mandatory degree of normative standards, environmental awareness, the supply of raw materials for CDW recycling units, and the sale of remanufactured products. Finally, this paper identifies the following management implications: (1) the government should prioritize the task of improving specific legislation and regulations, with a focus on a mandatory degree of normative standards. (2) CDW production units should put the task of improving environmental awareness high on their agenda, with a focus on the supply of raw materials for recycling units. (3) CDW recycling units should prioritize the issue of the sale of remanufactured products. This paper also provides a theoretical basis for revealing the critical factors of CDW recycling in other countries or regions.
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