In an estuary,tidal,wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its evolution.In the Huanghe(Yellow) River estuaries and nearby delta,there are many ...In an estuary,tidal,wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its evolution.In the Huanghe(Yellow) River estuaries and nearby delta,there are many small sediment-affected estuaries with a unique morphology,such as the Xiaoqing River estuary.In this study,we investigated the special evolution and genetic mechanism of the Xiaoqing River estuary by analyzing graphic and image data with a numerical simulation method.The results show that NE and NE-E tide waves are the main driving force for sandbar formation.Sediment shoals have originated from huge amounts of sediment from the Huanghe River,with consequent deposition at the Xiaoqing River mouth.The lateral suspended sediments beyond the river mouth move landward.Siltation takes place on the northern shoreline near the river mouth whereas erosion occurs in the south.The deposits come mainly from scouring of the shallow seabed on the northern side of the estuary.Storm surges speed up deposition in the estuary.Development of the sediment shoals has occurred in two steps involving the processes of growth and further southward extension.Although the southward shift increases the river curvature and length,the general eastward orientation of the estuary is unlikely to change.Processes on the adjacent shorelines do not affect the development of the sediment shoals.The study presents a morphodynamic evolutionary model for the Xiaoqing River estuary,with a long-term series cycle,within which a relatively short cycle occurs.展开更多
应用ArcGIS软件中的Topo to Raster工具、MATLAB软件中的人工神经网络及Surfer软件中自然邻点法,本文对使用差分GPS测量的青藏高原不同地区的冰碛垄数据进行了数字地貌模拟,从模拟精度、准确度、地貌晕渲、易操作性及后期定量分析等方...应用ArcGIS软件中的Topo to Raster工具、MATLAB软件中的人工神经网络及Surfer软件中自然邻点法,本文对使用差分GPS测量的青藏高原不同地区的冰碛垄数据进行了数字地貌模拟,从模拟精度、准确度、地貌晕渲、易操作性及后期定量分析等方面进行了分析对比。结果表明ArcGIS中的Topo to Raster工具较其他两种方法有较好的模拟精度;综合考虑各方面因素,ArcGIS软件在冰碛垄地貌的定量研究中具有优势。展开更多
To conduct a large-scale hydrologic-response and landform evolution simulation at high resolution,a complex physics-based numerical model,the Integrated Hydrology Model(InHM),was revised utilizing cluster parallel com...To conduct a large-scale hydrologic-response and landform evolution simulation at high resolution,a complex physics-based numerical model,the Integrated Hydrology Model(InHM),was revised utilizing cluster parallel computing.The parallelized InHM(ParInHM) divides the simulated area into multiple catchments based on geomorphologic features,and generates boundary-value problems for each catchment to construct simulation tasks,which are then dispatched to different computers to start the simulation.Landform evolution is considered during simulating and implemention in one framework.The dynamical Longest-Processing-Time(LPT) first scheduling algorithm is applied to job management.In addition,a pause-integratedivide-resume routine method is used to ensure the hydrologic validity during the simulation period.The routine repeats until the entire simulation period is finished.ParInHM has been tested in a computer cluster that uses 16 processors for the calculation,to simulate 100 years' hydrologic-response and soil erosion for the 117-km2 Kaho'olawe Island in the Hawaiian Islands under two different mesh resolutions.The efficiency of ParInHM was evaluated by comparing the performance of the cluster system utilizing different numbers of processors,as well as the performance of non-parallelized system without domain decomposition.The results of this study show that it is feasible to conduct a regional-scale hydrologic-response and sediment transport simulation at high resolution without demanding significant computing resources.展开更多
基金Supported by the Knowledge Innovative Program of Chinese Academy of Sciences(No.KZCX2-EW-207)the National Natural Science Foundation of China(Nos.41106041,40706035,40676037,41076031)+1 种基金the Open Fund of the Key Laboratory of Marine Resources and Environmental Geology, SOA(No.MASEG200807)the Marine Scientific Research and the Open Fund of the Key Laboratory of Marine Geology and Environment, Chinese Academy of Sciences(No.MGE2009KG04)
文摘In an estuary,tidal,wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its evolution.In the Huanghe(Yellow) River estuaries and nearby delta,there are many small sediment-affected estuaries with a unique morphology,such as the Xiaoqing River estuary.In this study,we investigated the special evolution and genetic mechanism of the Xiaoqing River estuary by analyzing graphic and image data with a numerical simulation method.The results show that NE and NE-E tide waves are the main driving force for sandbar formation.Sediment shoals have originated from huge amounts of sediment from the Huanghe River,with consequent deposition at the Xiaoqing River mouth.The lateral suspended sediments beyond the river mouth move landward.Siltation takes place on the northern shoreline near the river mouth whereas erosion occurs in the south.The deposits come mainly from scouring of the shallow seabed on the northern side of the estuary.Storm surges speed up deposition in the estuary.Development of the sediment shoals has occurred in two steps involving the processes of growth and further southward extension.Although the southward shift increases the river curvature and length,the general eastward orientation of the estuary is unlikely to change.Processes on the adjacent shorelines do not affect the development of the sediment shoals.The study presents a morphodynamic evolutionary model for the Xiaoqing River estuary,with a long-term series cycle,within which a relatively short cycle occurs.
文摘应用ArcGIS软件中的Topo to Raster工具、MATLAB软件中的人工神经网络及Surfer软件中自然邻点法,本文对使用差分GPS测量的青藏高原不同地区的冰碛垄数据进行了数字地貌模拟,从模拟精度、准确度、地貌晕渲、易操作性及后期定量分析等方面进行了分析对比。结果表明ArcGIS中的Topo to Raster工具较其他两种方法有较好的模拟精度;综合考虑各方面因素,ArcGIS软件在冰碛垄地貌的定量研究中具有优势。
基金supported by the National Basic Research Program of China ("973" Program) (Grant No. 2011CB409901-1)Zhejiang Provincial Natural Science Foundation of China (Grant No. R5110012)the E-Project of Microsoft Research Asia
文摘To conduct a large-scale hydrologic-response and landform evolution simulation at high resolution,a complex physics-based numerical model,the Integrated Hydrology Model(InHM),was revised utilizing cluster parallel computing.The parallelized InHM(ParInHM) divides the simulated area into multiple catchments based on geomorphologic features,and generates boundary-value problems for each catchment to construct simulation tasks,which are then dispatched to different computers to start the simulation.Landform evolution is considered during simulating and implemention in one framework.The dynamical Longest-Processing-Time(LPT) first scheduling algorithm is applied to job management.In addition,a pause-integratedivide-resume routine method is used to ensure the hydrologic validity during the simulation period.The routine repeats until the entire simulation period is finished.ParInHM has been tested in a computer cluster that uses 16 processors for the calculation,to simulate 100 years' hydrologic-response and soil erosion for the 117-km2 Kaho'olawe Island in the Hawaiian Islands under two different mesh resolutions.The efficiency of ParInHM was evaluated by comparing the performance of the cluster system utilizing different numbers of processors,as well as the performance of non-parallelized system without domain decomposition.The results of this study show that it is feasible to conduct a regional-scale hydrologic-response and sediment transport simulation at high resolution without demanding significant computing resources.
