Search

The stacking of impermissible materials in the disposal of dry fly ash is unprecedented in the last 40 years of power plant management in China, and their effect on the stability of the whole facility is uncertain. Due to the lack of relevant treatment experience, a more comprehensive method such as numerical modeling must be adopted for the final design. This paper set up a borehole database from geological logging data to obtain the distribution of the coal gangue solid waste. Then, it established an accurate three-dimensional mesh model through Rhino. Based on elastic–plastic mechanics, the finite difference code Flac3D 6.0 was employed to study the risk of the coal gangue as a dam foundation. A comparative analysis of the influence of the displacement method and the composite foundation method on subdam deformation and differential subsidence was conducted. The simulation revealed that the composite foundation method showed the best reductions: 70.57% in shear failure, 97.83% in tension failure, and 22.63% in maximum subsidence. Ultimately, the optimum stone column diameter of 0.5 m and the spacing of 6 m were proposed due to the standard deviation. [ABSTRACT FROM AUTHOR]

• The first framework for estimating plastic litter from aquaculture was developed. • The framework was applied to a plastic load survey of oyster farming in the Maowei Sea. • The plastic load from aquaculture approximates the plastic input of a river. • This source-based approach to plastic litter evaluation is suitable for management. • This framework can be extended to other aquaculture patterns. Aquaculture provides livelihoods for hundreds of millions of people, but it also forms a significant source of plastic litter that poses a serious hazard to aquatic ecosystems. How to assess and subsequently manage plastic loads from aquaculture is a pending and pressing issue for aquaculture sustainability, and an important concern for water environment monitoring and management. In this study, we developed the first framework for estimating plastic litter from aquaculture by combining data from satellite remote sensing, drones, questionnaires, and in situ measurements. By acquiring multidimensional (human and nature) and multiscale (centimeter to basin scale) data, this framework helped us understand the aquaculture farming patterns and its spatial and temporal evolution, and thus estimate the plastic load it generates and suggest effective management approaches. Applying this framework, we assessed the marine plastic load from oyster floating raft farming in the Maowei Sea, a typical mariculture bay in China, with an increasing farming area. Approximately 3840 tons of plastic waste is expected to be discharged into the sea in the next four years (the average service life of a floating raft) without improvements in aquaculture waste management. Strengthening governance, timely plastic removal, innovative replacement, and transforming farmers' behavior patterns are recommended as the subsequent measures for plastic management. This framework can be extended to other regions and other aquaculture patterns, and is applicable to local, regional, and global aquaculture plastic litter assessments. It is a source-based method for evaluating plastic pollution that is more conducive to subsequent plastic management than traditional post-contamination environmental monitoring. In the context of the global expansion of mariculture and the global commitment to action to combat plastic pollution, this approach could play a critical role in the investigation and management of plastic waste in aquatic environments. [Display omitted] [ABSTRACT FROM AUTHOR]

In the Anthropocene, marine microplastic debris has been rapidly increasing and interacting with wildlife. As apex predators, cetaceans have been proven to be ideal sentinel species to indicate ecosystem changes and umbrella and flagship species to help develop environmental management strategies. Here, we report the presence of microplastics in the intestines of Sousa chinensis for the first time, which highlights the potential impacts of microplastic pollution in coastal environments. Microplastics were detected in the intestinal contents of both adult and calf individuals, indicating that consumption of prey and unintentional ingestion are the potential pathways for microplastic accumulation in Sousa chinensis. The properties of the microplastics indicated that fibers, white and blue items, 1-5 mm items, and polyester were the predominant shapes, colors, sizes and plastic materials, respectively. More microplastics were detected in the foreguts and midguts than in the hindguts, which may be correlated with the specific intestinal structure of Sousa. This study indicates that coastal delphinids might suffer from microplastic pollution, even young calves. The sample size in this study is limited, whereas it's a starting point for assessing microplastics in the endangered coastal delphinid, Sousa. We suggest that assessments of the risks of microplastic consumption by cetaceans and the presence of microplastics in their habitats should be conducted at a global scale. Moreover, further works should be done to look for evidence of adverse effects of microplastics pollution on cetaceans., (Copyright © 2018 Elsevier B.V. All rights reserved.)