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.

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.

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.

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.

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.

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.

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.

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.

The rapid economic development in China places a large demand for energy, and as a result, thermal power plants in China are producing an enormous amount of coal fly ash (CFA) which causes severe environmental pollution. This paper briefly describes the current production and utilization status of CFA in China and identifies the challenges confronting sustainable CFA utilization as the Chinese economy is being transformed. These issues include a regional imbalance in supply and demand, reducing demand in the real estate industry as well as stricter laws for environmental protection. Viable directions for future CFA utilization are proposed, for example, production of CFA-based ceramic tiles, recovery of elemental resources, agricultural melioration, treatment of wastewater and flue gas, and production of high-volume CFA concretes. This paper has some guiding significance for sustainable and cleaner utilization of CFA in China and even worldwide. Graphical abstract

In the last decade, the approach to waste management has undergone severe changes. The urgent need to face the sustainable demand for energy and materials while limiting the burdens associated to traditional waste handling practices have figured out the concept of waste as a resource. New strategies boosting the extensive recovery and diverting waste from disposal activities have been promoted and framed in the wider context of the urban mining, promoting the full exploitation of waste as resource for either new materials or energy production. Such approach has been recently proposed to handle over 5 million tons of pretreated municipal solid waste produced and stored in the form of bales in Campania Region, in southern Italy, between 2000 and 2009. However, since the feasibility of this approach is related to the waste composition as well as to the selection process, an experimental study was performed at an industrial mechanical treatment plant to assess the potential for valorisation of this waste. Results showed that the overall sustainability of the urban mining strategies for the management of Campania waste bales is tightly linked to the flexibility of the selection process scheme to be adopted, which should make the waste recovery fit the market demand of either material or energy.