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Cities, the main place of human settlements, are required to offer high-quality environments to citizens. To achieve this, it is essential to overcome several mega challenges of urbanization, population growth, economic development, environmental deterioration, and climate change. Urban infrastructure construction is capable of enhancing economic growth and promoting urban sustainability, while it will lead to many environmental problems if the infrastructure construction is not properly planned and designed. To address this challenge, this study aims to understand how to ensure the construction land expansion sustainably in rapidly urbanizing cities. In particular, this study analyzed the suitability of construction land expansion in Nanchang, a rapid urbanizing city in China, from 1995 to 2015. The results indicate that the urban expansion speed from 1995 to 2005 was faster than that from 2005 to 2015. The construction land in Nanchang was expanding towards "all directions" and sprawled towards surrounding districts and counties from the original core areas. Nevertheless, about 70% of the Nanchang area was allowable construction area (highly suitable expansion, relatively suitable expansion, and basically suitable expansion areas), indicating that the abundant reserved land resources for urban construction. This study also identified multiple suitability expansion paths of construction land, providing a scientific guidance for the land use planning of Nanchang city. Overall, this study provides a reference to the understanding of the construction land expansion for the achievement of United Nations sustainable development goals. It can also promote the understanding of spatial territory planning and practically enhance the capabilities of land use planning and design.

The footprints of microplastics in the water bodies of urban agglomerations are largely dominated by superimposed anthropogenic influences. Understanding these influences and how they are correlated is essential to better understand the occurrence and variability of microplastics in different ecosystems. This study longitudinally assessed the abundance and distribution of microplastics in the water bodies of urban agglomerations at the watershed-scale in Shanghai Megacity. Particularly, the behavior of microplastics with the impacts of drainage system overflow in wet weather (WWF), land uses, and environmental management practices were explored. WWF can greatly aggravate microplastic pollution in aquatic environments. A systemic estimation based on detailed data was used to show that the annual load of microplastics discharged via WWF in the watershed area was 8.50 × 10 14 p/year, which was approximately six times larger than that discharged via the local Wastewater Treatment Plant effluent. Findings here contribute to research concerning the spatial variability of aquatic microplastics and the extent to which they are affected by land use. In descending order, the highest microplastic concentrations were found in heavy industrial > commercial/public/recreational > agricultural/light industrial > agricultural > and residential areas. The longitudinal pattern of microplastics observed in the water bodies suggested that there were superimposed effects of land use and hydrodynamics. This paper is the first to provide an integrated framework that demonstrates the significant role of environmental management practices in controlling the production and transmission of microplastics to receiving waters at a city-scale. Improved management of WWF might be a tangible solution that would help achieve an immediate and large-scale reduction of microplastics in sewage. Determining the optimized management practices for different weather or hydrological conditions could be an essential factor in decreasing microplastic concentrations and altering their flow-path pattern in a given region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)