scholarly journals An Analysis of the Periodic Evolution of the Jingjiang Sandbank in the Tidal Reach of the Yangtze River

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1652
Author(s):  
Ying Hu ◽  
Minxiong Cao ◽  
Aixing Ma ◽  
Xiping Dou ◽  
Yuncheng Wen
Keyword(s):  
Yangtze River ◽  
Fish Habitat ◽  
Evolution Process ◽  
Periodic Change ◽  
Main Body ◽  
The Yangtze River ◽  
Evolution Pattern ◽  
Term Change ◽  
Tidal Reach

The Jingjiang Sandbank (JJS) is located on the bank of the tidal reach in the Yangtze River. It experiences a periodic evolution process of increase, split, migration, and dissipation, which affects the current direction, fish habitat, navigation safety, etc. In this paper, the periodic evolution of the JJS is investigated based on 17 field bathymetric measurements of the river from 1999 to 2017. Firstly, six cycles of the evolution process of the sandbank are described, and the evolution pattern of the split detached bar and the main body of the sandbank are analyzed according to the migration tracks of the detached bars and the historical volume-change of the JJS, respectively. Then an empirical orthogonal function (EOF) is conducted on the historical measurements of the bathymetry. The first four eigenfunctions correspond to the time-averaged bathymetry, the long-term change of the pattern of bathymetry, the periodic change of the JJS, and the downstream migration of the split detached bar, and the periodic change of the rip at the back of JJS. It is pointed out that the construction of two waterway regulation projects might have changed the evolution pattern of the JJS permanently.

Monitoring permafrost changes in the Yangtze River source region of the Qinghai-Tibetan Plateau using differential SAR interferometry

2020 ◽  
Author(s):  
Lingxiao Wang ◽  
Lin Zhao ◽  
Huayun Zhou ◽  
Shibo Liu ◽  
Xiaodong Huang ◽  
...  
Keyword(s):  
Active Layer ◽  
Yangtze River ◽  
Ground Deformation ◽  
Source Region ◽  
Deformation Monitoring ◽  
Tibet Plateau ◽  
Permafrost Degradation ◽  
The Yangtze River ◽  
Ground Ice

<p>Qinghai-Tibet Plateau (QTP) has the largest high-altitude permafrost zone in the middle and low latitudes. Substantial hydrologic changes have been observed in the Yangtze River source region and adjacent areas in the early 21st century. Permafrost on the QTP has undergone degradation under global warming. The ground leveling observation site near Tangula (33°04′N, 91°56′E) located in the degraded alpine meadow indicates that the ground has subsided 50mm since 2011. The contribution of permafrost degradation and loss of ground ice to the hydrologic changes is however still lacking. This study monitors the permafrost changes by applying the Small BAseline Subset InSAR (SBAS-InSAR) technique using C-band Sentinel-1 datasets during 2014-2019. The ground deformation over permafrost terrain is derived in spatial and temporal scale, which reflects the seasonal freeze-thaw cycle in the active layer and long-term thawing of ground ice beneath the active layer. Results show the seasonal thaw displacement exhibits a strong correlation with surficial geology contacts. The ground leveling data is used to validate the ground deformation monitoring results. Then, the ground deformation characteristics are analyzed against the landscape units. Last, the long-term inter-annual displacement value is used to estimate the water equivalent of ground ice melting.</p>

Research on Continuous Traffic Safety Evaluation of Yangtze River Shipping

2013 ◽  
Vol 442 ◽  
pp. 617-622 ◽  
Author(s):  
Kai Jin Xu ◽  
Qin Liu ◽  
Lei Xu
Keyword(s):  
Traffic Safety ◽  
Yangtze River ◽  
Evaluation Model ◽  
Safety Evaluation ◽  
Scientific Basis ◽  
The Yangtze River ◽  
Affecting Factors ◽  
Analytic Hierarchy ◽  
Safety Mechanism

Traffic safety has characteristics of long-term and arduous, and continued safety is the essential goal of safety, the continued safety of Yangtze River shipping is not only an important part of Yangtze River safety culture, but also a concrete manifestation of long-term safety mechanism. This paper analyzes the affecting factors of the Yangtze River shipping safety, from the perspective of sustainable safety, extract with operational index of safety evaluation, construct of the Yangtze River shipping safety evaluation model, combined with the improved analytic hierarchy process , estimates the main aspects that affects the continued safety of the Yangtze River shipping , and the research results can provide scientific basis for the long-term management of Yangtze River shipping safety.

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