A 3-D unstructured-grid, finite-volume coastal ocean model (FVCOM) was used to study the tides and tidal currents in the Lianzhou Bay and adjacent areas. The simulation results were in good agreement with observatio...A 3-D unstructured-grid, finite-volume coastal ocean model (FVCOM) was used to study the tides and tidal currents in the Lianzhou Bay and adjacent areas. The simulation results were in good agreement with observations. The co-tidal maps of K1 , O1 , and M2 indicated that K1 and O1 were mostly standing waves outside the Lianzhou Bay, while M2 had a largely propagating character. However, all three constituents became propagating waves when entering the Lianzhou Bay, due to the shallow waters. The tidal current ellipses showed the characters of K1 , O1 , and M2 constituents: K1 and O1 were rotating outside the bay, but rectilinear along the water channels inside the bay; M2 was mostly rectilinear over the whole area. The tidal-induced residual current shows the flow was divided into two branches by the Guantouling Peninsula: one turned to flow west; the other was blocked by the southern boundary of the peninsula, creating a clockwise circulation. In Lianzhou Bay, there were two circulation systems, a cyclonic one at the top of the bay and an anti-cyclonic at the mouth.展开更多
Formation and evolution of rural settlement patterns in Lianzhou City,Guangdong Province were analyzed from the perspective of space and time,on the basis of its gazetteer and relevant historical data.The results show...Formation and evolution of rural settlement patterns in Lianzhou City,Guangdong Province were analyzed from the perspective of space and time,on the basis of its gazetteer and relevant historical data.The results show that Lianzhou was first founded in the sixth year of Yuanding Period of the Western Han Dynasty,and its development could be roughly classified into 6 stages according to the construction of south–north traffic lines and regional development progress,and it witnessed the fastest development in the Ming and Qing Dynasty.In terms of spatial distribution,rural settlements in the local area show spatial continuity,Lianzhou Town is the core of rural settlement growth in the city,and towns with the most concentrated rural settlements in all stages are located in central-west and northeast parts of the city,and those with lower density of rural settlements are mostly located in minority regions in the north and mountainous areas in the east.On the basis of the above facts,the paper studies the influence of natural geological conditions,immigrant,traffic,economic development and ethnic composition on the establishment and development of rural settlements in Lianzhou City.展开更多
This study investigates the physical conditions(water depth, current speed, salinity, temperature) in Lianzhou Bay, a shallow coastal bay in southern China, during two expeditions in the dry and wet seasons of 2011. B...This study investigates the physical conditions(water depth, current speed, salinity, temperature) in Lianzhou Bay, a shallow coastal bay in southern China, during two expeditions in the dry and wet seasons of 2011. Based on these expedition data, basic hydrodynamic parameters like Brunt-V?is?l? Frequency, Richardson Number, Rossby radius, and Resonance Period are calculated. The results show that Lianzhou Bay is characterized by comparatively small quantity of freshwater input and weak stratification. Strong tides, which are spatially uniform within the bay, cause turbulent mixing. Residence time of the water is shorter in winter due to a stronger coastal current in that season. Consideration of the water movement may help to reduce the harmful ecological impact of aquaculture waste water discharge.展开更多
The concept of water age is applied to calculate the timescales of the transport processes of freshwater in Lianzhou Bay,using a model based on ECOMSED.In this study,water age is defined as the time that has elapsed s...The concept of water age is applied to calculate the timescales of the transport processes of freshwater in Lianzhou Bay,using a model based on ECOMSED.In this study,water age is defined as the time that has elapsed since the water parcel enters the Nanliu River.The results show that the mean age at a specified position and the runoff of the Nanliu River are well correlated and can be approximately expressed by a natural logarithmic function.During the neap tide,it takes 70,60 and 40 days in the dry,normal and rainy seasons for water to travel from the mouth of the Nanliu River to the northeast of Lianzhou Bay,respectively,which is not beneficial to water exchange in the bay.Tides significantly influence the model results;it takes five less days for the tracer to be transported from the mouth of the Nanliu River to the north of Guantouling during the spring tide than during the neap tide.展开更多
基金supported by the special fund for the Ocean Public Welfare Scientific Research Project, State Oceanic Administration, People's Republic of China(Grant No. 200805065)
文摘A 3-D unstructured-grid, finite-volume coastal ocean model (FVCOM) was used to study the tides and tidal currents in the Lianzhou Bay and adjacent areas. The simulation results were in good agreement with observations. The co-tidal maps of K1 , O1 , and M2 indicated that K1 and O1 were mostly standing waves outside the Lianzhou Bay, while M2 had a largely propagating character. However, all three constituents became propagating waves when entering the Lianzhou Bay, due to the shallow waters. The tidal current ellipses showed the characters of K1 , O1 , and M2 constituents: K1 and O1 were rotating outside the bay, but rectilinear along the water channels inside the bay; M2 was mostly rectilinear over the whole area. The tidal-induced residual current shows the flow was divided into two branches by the Guantouling Peninsula: one turned to flow west; the other was blocked by the southern boundary of the peninsula, creating a clockwise circulation. In Lianzhou Bay, there were two circulation systems, a cyclonic one at the top of the bay and an anti-cyclonic at the mouth.
基金Sponsored by Fundamental Research Funds for the Central Universities(GK201303006)National Natural Science Foundation of China(41171139)Key Projects of Humanities and Social Sciences Research Base of Guangdong Colleges and Universities(09JDXM84001)
文摘Formation and evolution of rural settlement patterns in Lianzhou City,Guangdong Province were analyzed from the perspective of space and time,on the basis of its gazetteer and relevant historical data.The results show that Lianzhou was first founded in the sixth year of Yuanding Period of the Western Han Dynasty,and its development could be roughly classified into 6 stages according to the construction of south–north traffic lines and regional development progress,and it witnessed the fastest development in the Ming and Qing Dynasty.In terms of spatial distribution,rural settlements in the local area show spatial continuity,Lianzhou Town is the core of rural settlement growth in the city,and towns with the most concentrated rural settlements in all stages are located in central-west and northeast parts of the city,and those with lower density of rural settlements are mostly located in minority regions in the north and mountainous areas in the east.On the basis of the above facts,the paper studies the influence of natural geological conditions,immigrant,traffic,economic development and ethnic composition on the establishment and development of rural settlements in Lianzhou City.
基金the financial support from the German Federal Ministry for Education and Research(BMBF)to the Leibniz-Zentrum für Marine Tropenkologie GmbH(ZMT),Germany,for the project‘The Role of Mangroves for Biogeochemical Fluxes into the Coastal Ecosystemsunder the Influence of Anthropogenic Alterations’as part of the Sino-German Research Project‘BEIBU-Holocene environmental evolution and anthropogenic impact of Beibu Gulf,South China Sea’,WTZ China(Grant No.03F0607B) is acknowledged.
文摘This study investigates the physical conditions(water depth, current speed, salinity, temperature) in Lianzhou Bay, a shallow coastal bay in southern China, during two expeditions in the dry and wet seasons of 2011. Based on these expedition data, basic hydrodynamic parameters like Brunt-V?is?l? Frequency, Richardson Number, Rossby radius, and Resonance Period are calculated. The results show that Lianzhou Bay is characterized by comparatively small quantity of freshwater input and weak stratification. Strong tides, which are spatially uniform within the bay, cause turbulent mixing. Residence time of the water is shorter in winter due to a stronger coastal current in that season. Consideration of the water movement may help to reduce the harmful ecological impact of aquaculture waste water discharge.
文摘The concept of water age is applied to calculate the timescales of the transport processes of freshwater in Lianzhou Bay,using a model based on ECOMSED.In this study,water age is defined as the time that has elapsed since the water parcel enters the Nanliu River.The results show that the mean age at a specified position and the runoff of the Nanliu River are well correlated and can be approximately expressed by a natural logarithmic function.During the neap tide,it takes 70,60 and 40 days in the dry,normal and rainy seasons for water to travel from the mouth of the Nanliu River to the northeast of Lianzhou Bay,respectively,which is not beneficial to water exchange in the bay.Tides significantly influence the model results;it takes five less days for the tracer to be transported from the mouth of the Nanliu River to the north of Guantouling during the spring tide than during the neap tide.