Declining sediment discharge in the Yangtze River from 1956 to 2017: Spatial and Temporal changes and their causes

In this study, an empirical curve describing the relation between erosion and deposition rate and water/sediment discharge was developed based on the recent evolution trend of the submerged delta at the Yangtze River Mouth, and the one-dimensional mathematical model for unsteady water-and sediment-transport was calibrated using the water and sediment discharge data after water impounding to predict the water and sediment discharge for the future 10 years and the future evolution of the submerged delta at the Yangtze River Mouth. The results showed that the 10 m and 20 m isobaths areas of the submerged delta changed with the water and sediment discharge from siltation to siltation slowing down to erosion. Siltation increased with large amount of rain received by the watershed during 1997-2000, while continuous retreat of erosion happened during 2000-2009. Using the one-dimensional mathematical model for river water and sediment calibrated and tested with data collected after impounding, the water and sediment discharges were calculated for Series 60 and 90, and its evolution in 2013-2022 was predicted for the delta. For Series 60, its 10 cm and 20 cm isobaths areas showed alternative scour and siltation, while the delta showed trends of erosion. For Series 90, its 10 m and 20 m isobaths showed substantial siltation in flood years. The water and sediment discharges since the Three Gorges Reservoirs was filled were lower than the calculated results for both Series 60 and 90. If the water and sediment discharges continue to decease, the delta will take an erosion trend.

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Seasonal variations of sediment discharge from the Yangtze River before and after impoundment of the Three Gorges Dam

Geomorphology ◽

10.1016/j.geomorph.2008.09.004 ◽

2009 ◽

Vol 104 (3-4) ◽

pp. 276-283 ◽

Cited By ~ 271

Author(s):

Kehui Xu ◽

John D. Milliman

Keyword(s):

Seasonal Variations ◽

Yangtze River ◽

Three Gorges Dam ◽

Three Gorges ◽

Sediment Discharge ◽

The Yangtze River ◽

The Three Gorges ◽

Before And After ◽

The Three Gorges Dam

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Spatio-temporal changes of cropland soil pH in a rapidly industrializing region in the Yangtze River Delta of China, 1980–2015

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2018.11.015 ◽

2019 ◽

Vol 272 ◽

pp. 95-104 ◽

Cited By ~ 8

Author(s):

Enze Xie ◽

Yongcun Zhao ◽

Haidong Li ◽

Xuezheng Shi ◽

Fangyi Lu ◽

...

Keyword(s):

Soil Ph ◽

Yangtze River ◽

Yangtze River Delta ◽

Temporal Changes ◽

River Delta ◽

The Yangtze River ◽

Spatio Temporal ◽

The Yangtze River Delta

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Study on Spatial-Temporal Change of Urban Green Space in Yangtze River Economic Belt and Its Driving Mechanism

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182312498 ◽

2021 ◽

Vol 18 (23) ◽

pp. 12498

Author(s):

Chunyu Chen ◽

Linglan Bi ◽

Kuanfan Zhu

Keyword(s):

Spatial Distribution ◽

Yangtze River ◽

Green Space ◽

Temporal Changes ◽

Urban Green Space ◽

Sustainable Urban Development ◽

Driving Mechanism ◽

The Yangtze River ◽

Rapid Urbanization ◽

Urban Green

Urban green space plays an important role in beautifying the environment, improving the quality of life of residents, and promoting sustainable urban development. Rapid urbanization has led to great changes in the spatial structure and layout of urban green space. It is urgent to put forward the sustainable development strategy of green space through the research on the change of urban green space. Based on the geographical spatial differences of urban green space and integrating the factors of economy, society, industry, land use, and the environment, we constructed a research framework of “space-supply-demand” integration of urban green space by GI and geodetector methods, and we conducted an empirical study on the spatial–temporal changes of urban green space and its driving mechanism in prefecture-level cities along the Yangtze River Economic Belt in China. First, the urban green space along the Yangtze River Economic Belt is concentrated in spatial distribution, while uneven development appears in urban greening among the zones. Second, the influence of different factors on urban green space change varies greatly and can be divided into three types: key factors, important factors, and auxiliary factors. The driving mechanism of the spatial distribution of urban green space supply and demand is quite different, but urban population and commercial service facilities land are their key influence factors, having a comprehensive influence on the spatial–temporal changes of urban green space. Third, the factors are classified into three categories of high, medium, and low levels according to the mean of interacting forces; in particular, the factors of per capita GDP, utility land, industrial smoke (dust) emissions, and other factors have a very strong interactive effect with other factors. Fourth, according to the spatial distribution characteristics of urban green space and its driving mechanism, this paper puts forward planning and policy suggestions, providing reference for other areas to deal with the green space change.

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