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• New sedimentary evidences of high-magnitude floods in the Purlung Tsangpo basin. • Reconstruct the paleo-discharge of 37,000 m3/s, possibly resulting from outburst flood. • The Paleo-flood event occurred 2.2–2.6 cal kyr BP, following Holocene climate transition. Catastrophic flood events are the most devastating natural hazard in the world, and direct human observation or instrumental/systematic measurement cannot capture the full range of their frequency-magnitudes. It is essential to reconstruct large-magnitude, rare floods that are recorded in landforms and sediments. Recently, palaeohydrology studies associated with Holocene palaeofloods in Himalayan rivers have been gaining attention. Exceptional Holocene outburst floods have been invoked as a highly efficient erosion agent contributing to the rapid incision of the Tsangpo Gorge. Despite its significance, palaeoflood records upstream of Tsangpo Gorge have rarely been explored. This study presents a series of flood deposits consisting of laminated silt and sand or repeated cross-bedding sets, which points to high-magnitude flood. Inverse hydraulic modelling of the step-backwater method based on HEC-RAS software was applied to acquire the water surface profile under varying peak discharge scenarios. The discharges of palaeofloods were estimated by relating elevations of flood features to water surface profiles calculated for the reach. The result provides a minimum estimate of the peak discharge of approximately 3.70 × 104 m3/s with a maximal depth of up to 47 m. The overestimation of the peak discharge due to post-event channel incision is up to 3000 m3/s. Seven charcoal 14C dates give a narrow age range between 2.2 and 2.6 ka cal BP. This flood occurred only a few hundred years after a period of climate transition at ∼ 3 ka BP, which was prone to hydrological extremes. Since the reconstructed palaeodischarge is significantly beyond the scope of either rainfall floods or glacial lake outburst floods, it can be inferred that the breaching of an upstream landslide dam is the most reasonable origin. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) is a reflection of the culture that generates it and has a negative impact on the health of the humans and the environment. In the global context, people are abandoning increasing volumes of garbage, and the content of that waste is becoming more complicated than it has ever been, as plastic and electronic consumer goods spread. At the same time, the world is rapidly urbanizing. These changes place a burden on cities to manage garbage appropriately on both a social and environmental level. Globally, extensive research has been conducted to develop a comprehensive MSW management system that includes treatment. The primary objective of this article is to examine municipal solid waste in eight of China's eastern coastal regions. With the use of this review, we found that MSW generation is increasing in Shandong, Guangdong, Zhejiang, and Fujian provinces, but declining in other eastern coastal cities, provinces, and special zones. Furthermore, municipal solid waste in China is treated utilizing 52 percent landfill, 45 percent incineration, and 3 percent composting techniques, resulting in significantly lower usage efficiency than in developed countries. The effectiveness of China's municipal waste management system must be improved. In addition, this review examines MSW management issues and prospects in China, as well as recommendations for strengthening the MSW management system. [Display omitted] • Impact of municipal solid waste on human health and the environment is explored. • Waste management challenges due to rapid urbanization are summarized. • Characteristics of municipal solid waste and relevant laws are reviewed. • Integrated municipal solid waste management and technologies are proposed. [ABSTRACT FROM AUTHOR]