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Polybrominated diphenyl ethers in indoor and outdoor dust from Southeast Asia: An updated review on contamination status, human exposure, and future perspectives
2021
Hoang, Anh Quoc | Tran, Tri Manh | Tu, Minh Binh | Takahashi, Shin
Contamination status, potential emission sources, environmental fate, and human exposure risk of polybrominated diphenyl ethers (PBDEs) are reviewed for indoor and outdoor dust from Southeast Asian countries, under an international comparison point of view. PBDEs have been widely detected in house, workplace, car, and road dust samples collected from Indonesia, Philippines, Singapore, Thailand, and Vietnam. The highest PBDE levels up to hundreds of μg/g were found in settled dust from some e-waste processing areas in Thailand and Vietnam. Concentrations of PBDEs in house, car, and road dust from this region were generally lower than those reported in China and Western developed countries. BDE-209 was the most predominant congener in almost all analyzed samples, reflecting the widespread application of materials and products treated with commercial deca-BDE mixtures in this region. The market demand and application rate of commercial PBDE mixtures in Southeast Asia were lower than those documented for other regions in the world. As a result, PBDE contamination levels in the environments (e.g., indoor and outdoor dust) and associated risks in these countries were not significantly high. However, more attention should be paid to informal processing activities and management strategies for modern wastes such as e-waste, plastics, and end-of-life vehicles. There exist several knowledge gaps about spatiotemporal trends, potential sources, risk assessment, inventory, management, and legislation regarding PBDEs in dust from this region, which should be filled by additional comprehensive, detailed studies with relevant inter-country/regional monitoring schemes.
Show more [+] Less [-]Undesirable odour substances (geosmin and 2-methylisoborneol) in water environment: Sources, impacts and removal strategies
2022
Abd El-Hack, Mohamed E. | El-Saadony, Mohamed T. | Elbestawy, Ahmed R. | Ellakany, Hany F. | Abaza, Samar S. | Geneedy, Amr M. | Salem, Heba M. | Taha, Ayman E. | Swelum, Ayman A. | Omer, Fatima A. | AbuQamar, Synan F. | El-Tarabily, Khaled A.
Off-flavours in fish products generated from recirculating aquaculture systems (RAS) are a major problem in the fish farming industry affecting the market demand and prices. A particular concern is the muddy or musty odour and taste in fish due to the presence of secondary metabolites geosmin and 2-methylisoborneol (2-MIB), produced by actinobacteria (mainly Streptomyces), myxobacteria and cyanobacteria. Off-flavours have deteriorated the quality of fish, rendering their products unfit for human consumption. The process of odour removal requires purification for several days to weeks in clean water; thus this leads to additional production costs. Geosmin and 2-MIB, detected at extremely low odour thresholds, are the most widespread off-flavour metabolites in aquaculture, entering through fish gills and accumulating in the fish adipose tissues. In this review, we aimed to determine the diversity and identity of geosmin- and 2-MIB-producing bacteria in aquaculture and provide possible strategies for their elimination.
Show more [+] Less [-]Development characteristics, influencing mechanism and coping strategies of resource-based cities in developing countries: a case study of urban agglomeration in Northeast China
2022
Wang, Yufeng
The transformation of resource-based cities and coordinated regional development are of great value to global urbanization and sustainable economic development in developing countries. Based on Landsat satellite monitoring data and urban economic data, statistical analysis and geospatial model were used to analyze the characteristics of urban development in urban agglomeration in Northeast China from 2000 to 2020, and the influencing mechanism was quantitatively revealed. The results show that the expansion of urban agglomerations rate reached its peak from 2005 to 2010, and then the expansion rate continued to decline. The resources of central cities were concentrated, while the development of sub-central cities was weak. The overall urbanization rate slows down, the scale difference between high-order cities and low-order cities expands, and the regional urban system shifts from balanced development to polarized development. The overall development of urban agglomerations shows a centripetal agglomeration characteristic centered on the Harbin Changchun-Daqing and Central and southern Liaoning Economic belt. Its west expands faster than the East, and its south expands faster than the north. The driving factors of urban agglomeration development are mainly administrative power, followed by market power, external power and weak internal power. From the point of time and space, the external power is on the rise, while the internal power is affected by the industrial adjustment and lacks the staying power. In view of the coordinated development of resource-based cities, this paper proposes to establish the linkage and coordination mechanism of integrated development of urban agglomeration, speed up the construction of unified market system, carry out transformation positioning according to market demand and implement differentiation policy.
Show more [+] Less [-]Biopesticides extension and rice farmers’ adoption behavior: a survey from Rural Hubei Province, China
2022
Huang, Yanzhong | Li, Zhaoliang | Luo, Xiaofeng | Liu, Di
Although the beneficial effects of the agricultural extension of farmers’ biopesticides adoption have been largely demonstrated, the questions of what approaches can better extend biopesticides and how to improve their effectiveness still need to be explored. In a survey of 1148 rice farmers in Hubei Province, China, the technology supply and demand theory is used to explain the low efficiency of biopesticides extension. The endogenous switching probit model is used to estimate the impact of biopesticides technology publicity, training, demonstration and subsidies on farmers’ adoption. The results show that biopesticides extension can promote rice farmers’ adoption probability by 10.3 ~ 11.7%. And technology demonstration is currently the best way to extend biopesticides. Moreover, inadequate supply and demand of biopesticides are important for explaining the inefficiency of biopesticides extension in China. Extending biopesticides is better for farmers with smaller scales, younger ages, and lower education and for those who are cooperative members. Therefore, we should not only actively conduct biopesticides demonstration but also more importantly induce farmers’ biopesticides demand and secure the market supply of biopesticide products. These findings will provide useful guidance for biopesticides extension and pesticides reduction in China and other developing countries.
Show more [+] Less [-]Quantifying ecosystem service mismatches for land use planning: spatial-temporal characteristics and novel approach—a case study in Jiangsu Province, China
2022
Zhou, Yangfan | Li, Jianguo | Pu, Lijie
Land use and land cover changes associated with urbanization have had a significant influence on ecosystem services (ESs), but previous studies have insufficiently focused on the relationships between ES supply and demand; these relationships are seldom considered in the science-policy frameworks of land use planning. In this study, a specific supply-demand indicator was constructed to measure ES supply and demand and their disparity across multiple scales in Jiangsu Province from 2000 to 2018. High spatial heterogeneity and mismatches of ES supply and demand were found in water yield, grain production, carbon sequestration, soil conservation, heat regulation, and recreation services. At provincial scale, the supplies of carbon sequestration and heat regulation services were smaller than their demands. At the 1-km² grid scale, the ES supply and demand mismatches in urban areas were more serious than those in surrounding areas, especially for carbon sequestration and recreation services. Five ES supply-demand risk zones were identified based on the current status and trends of all ES supply and demand. Southern Jiangsu generally had high risks of ES mismatch, which should be reduced by strategic planning. Constructing the ES supply-demand indicator is a novel practice that assists in evaluating environmental issues and integrating them into further development decisions. This paper suggests that governments should reduce ES mismatches with reference to local conditions (economic development, industrial type, and ecological carrying capacity) and the actual situation of ES supply and demand.
Show more [+] Less [-]System dynamics approaches to assess the impacts of climate change on surface water quality and quantity: case study of Karoun River, Iran
2021
Ganji, Fatemeh | Nasseri, Mohsen
The aim of this research is to gain a better understanding of the effects of climate change with a comprehensive and dynamic perspective. Therefore, by using the System Dynamics (SD) approach to simulate the effects of climate change on the quality and quantity of the Karoun River and regarding the water supply and demand systems in the region and their feedback relations, a model was developed in Vensim. CGCM3 outputs under A2, B1, and A1B emission scenarios have been used to investigate the effects of climate change on both the quality/quantity of the water resources system. Also, to determine the effects of climate change on agricultural demand, the water requirement of selected crops for the next period (2015–2050) has been calculated via CROPWAT model. The results show that the maximum and minimum temperature and evaporation will increase. The results of the developed SD model show that if the current development process continues under all three climate change scenarios, the system will be able to meet the domestic, industrial, and environmental demand. However, the supply of agricultural demand will be deficient. Also, the average EC value in Ahvaz station under three emission scenarios has increased more than 21%, compared to the 15-year average. The average pH value did not change much. Then, several proposed management scenarios were evaluated to improve system performance. The results show that the scenario of optimal operation of upstream dams has the best performance. However, due to the unrealistic growing trend, despite applying this scenario, the development of the agricultural sector will fail down after a few years. Therefore, to reach a long-term solution to the problem of water shortage, the growth trend of this sector for the next period should be reviewed in light of the effects of climate change.
Show more [+] Less [-]Optimization of competitive supply chains with retailers’ horizontal cooperation and consumers’ green preference
2021
Shang, Wenfang | Teng, Liangliang | Yang, Jian-bo
With the wider recognition of the concept of environmental protection and sustainable development, more and more manufacturers have begun to implement green manufacturing strategies. However, green development is a gradual process, and the coexistence of ordinary and green products is common. This paper examines the competition between ordinary products and green ones based on supply chains, and discusses the impact of retailers’ horizontal cooperation on pricing, greenness, market demand, profit, and other related decisions and results. Model solutions and numerical experiments have shown that consumers’ green preference (CGP) has a positive impact on the results of green products and negative effects on those of ordinary ones; however, the impact of competition intensity (CI) is more complex, and the trend tends to change if it exceeds a certain critical value. In general, cooperation encourages retailers to raise prices and make manufacturers lower wholesale prices, but the retail and wholesale prices of green products are always higher than the corresponding prices of ordinary ones. Market demand can be reduced due to cooperation, but it is conducive to strengthening green products’ greenness. However, if CI exceeds a certain threshold, the greenness will be weakened by cooperation. Both retailers can benefit from cooperation easily and they always reach a win-win situation, but manufacturers suffer badly as a result. Nevertheless, when CI is weak, cooperation will bring a greater profit improvement to the whole chain of ordinary products; in this case, if a retailer is willing to compensate for a manufacturer’s profit loss and help it benefit from cooperation, the manufacturer will encourage the retailer to cooperate horizontally with the green retailer, but the green chain will be seriously damaged. When CI is strong, the greenness of green products is not obvious enough, and cooperation can bring some chances to achieve a win-win situation for two chains; if the green retailer can obtain a larger share from cooperation under this scenario, it can also enable its manufacturer to obtain compensation and change the profit increment from negative to positive. From an overall perspective, when CI is very weak or very strong, horizontal cooperation is conducive to improving the profit of the entire supply chain competition system, but when CI is relatively flat, independent operation for each chain is more advantageous; if the competition status is stable and unchanged, independent competition will be superior to horizontal cooperation.
Show more [+] Less [-]Exploring the impact of tourism and energy consumption on the load capacity factor in Turkey: a novel dynamic ARDL approach
2022
Pata, Ugur Korkut | Balsalobre-Lorente, Daniel
In the last two decades, the tourism and energy sectors have grown rapidly and boosted economic growth, but it is inevitable that these sectors will cause environmental changes. So far, attempts have been made to determine the impact of the tourism and energy sectors on environmental degradation by examining pollution indicators such as CO₂ emissions and ecological footprint. However, these indicators neglect the supply side of the environment. In this context, this paper, for the first time, examines the influence of tourism, income, and energy consumption on the load capacity factor that results from dividing biocapacity by ecological footprint. Thus, the study aims to conduct a comprehensive sustainability analysis for Turkey by assessing the environmental quality on the supply and demand side. For this purpose, the study employs the novel dynamic Autoregressive-Distributed Lag (ARDL) simulations for the period 1965–2017, and the results indicate that tourist arrivals, energy consumption, and economic growth have a negative long run effect on the load capacity factor. Among these factors, only economic growth exerts a significant impact on the load capacity factor in both the short and long run. In the long run, the negative environmental effect of economic growth is less than in the short run. Therefore, the environmental Kuznets curve hypothesis is valid for Turkey. Based on the results, some policy recommendations are proposed to help Turkey improve its environmental quality.
Show more [+] Less [-]The influencing factors and hierarchical relationships of offshore wind power industry in China
2021
Xu, Yan | Yang, Kun | Zhao, Guohao
As a new and cost-effective renewable energy power generation technology, offshore wind power is getting more and more attention. The development of offshore wind power industry is affected by policy-making, technology management, resources and environment, market supply and demand, and the relationship among the influencing factors is complex. This paper analyzes the factors that affect offshore wind power industry from a unique and comprehensive perspective. Fourteen factors are selected and interpretative structural model (ISM) is established to study the relationship between the influencing factors of offshore wind power industry. The results show that 14 influencing factors can be divided into five levels: the first level is the surface factors, including the economic incentive policy, operation mechanism, industrial chain, energy market mechanism, investment, and financing mechanism; the second and third levels are the intermediate factors, including generation cost, operation management, and offshore wind power technology; the fourth and fifth levels are deep-seated factors, including development planning and grid price, site selection, R&D investment, environmental protection policy, and offshore wind power supply. Deep-seated factors have a direct impact on the intermediate factors, the intermediate factors have an important impact on the surface factors, and the surface factors directly affect the development of offshore wind power industry. The influence of the 14 factors selected in this paper on offshore wind power industry is from bottom to top, from deep to shallow.
Show more [+] Less [-]Identification of ecosystem services supply and demand and driving factors in Taihu Lake Basin
2022
Li, Jinghui
A comprehensive understanding of the multiple factors affecting ecosystem services (ESs) supply and demand balance is essential for effective ecosystem management and policy making. However, the importance of individual factors for ES balance is still unclear. Using Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) models and Structural Equation Modeling, I mapped the supply–demand balance of four types of ESs (carbon sequestration, water yield, soil conservation, and recreation) in Taihu Lake Basin, China, and quantified the causal relationships between multiple factors and ES balance. The results revealed spatial heterogeneity and imbalance in ES supply and demand in the basin, with the greatest imbalances in built-up city center areas. ES balance was influenced by multiple factors, but particularly normalized difference vegetation index (NDVI), elevation, precipitation, and human disturbance. For appropriate watershed management in the future, it is recommended that numbers of small-scale community parks in city centers be increased and that green space be expanded in the suburbs, implementing multi-objective ES management systems and step-by-step implementation plans, and optimizing the configuration of natural ecosystems by creating buffer strips for built-up areas. By carefully managing ES supply–demand balance and associated influencing factors, ecosystem status and human well-being in Taihu Lake Basin, and in other similar basins, can be substantially improved.
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