We present a GIS-based habitat suitability index(HSI) model to identify suitable areas for Zostera marina L. restoration in the subtidal zone of Xiaoheishan Island. The controlling factors in the model,in order of imp...We present a GIS-based habitat suitability index(HSI) model to identify suitable areas for Zostera marina L. restoration in the subtidal zone of Xiaoheishan Island. The controlling factors in the model,in order of importance,are Secchi depth,sediment composition,water temperature,salinity,current velocity,water depth and nutrient quality. Specific factor piecewise functions have been used to transform parameter values into normalized quality indexes. The weight of each factor was defined using expert knowledge and the analytic hierarchy process(AHP) method. All of the data thus obtained were interpolated using the inverse distance weighted(IDW) interpolation method to create maps for the entire region. In this study,the analysis of habitat suitability in the subtidal zone of Xiaoheishan Island was conducted for four seasons. According to the GIS-based HSI model,the optimal habitat of Z ostera marina L. appears in spring,although habitat remains suitable all year round. On the whole,the optimum site for eelgrass restoration is located in the eastern region,followed by the western and southern regions. We believe that the GIS-based HSI model could be a promising tool to select sites for Z ostera marina L. restoration and could also be applicable in other types of habitat evaluation.展开更多
Containerization with its increasing share in seaborne trade highlights the importance of assessing container terminals performance indicators. The world economical situation and the global container market have impro...Containerization with its increasing share in seaborne trade highlights the importance of assessing container terminals performance indicators. The world economical situation and the global container market have improved slightly after the 2008 world economical crises. Egyptian container terminals are important to serve the world liner services in particular the main east-west routes. Egypt is considered the leading country in Africa and the 18th worldwide in serving the liner markets. Alexandria container terminal as a medium size terminal shows an acceptable super/infra structure facilities and throughput. The analysis of Alexandria container terminal performance indicators from 2007 to 2011 shows a slightly progressive trend. Selected indicators, reflecting production, productivity, utilization and service measures, were used according to the available data. Terminal production shows a slight increasing demand concerning number of vessels and TEUs (Twenty Equivalent Units). Furthermore, productivity indicators proved remarkable development in moves per working hours rather than moves per hours in port, deducing lack of port services accompanying cargo handling. Moreover, Utilization measurements show the terminal occupancy ratio fluctuating from 45% to 67% with slight development. Finally, Service measures show progress in vessels turnaround time, while long wasted time consumed in processes rather than operation was observed.展开更多
Abstract: Because of the complex topography in southwest region of China, the water level of the inland river has a large amplitude of variation which causes a frequent diversification of water content in the river s...Abstract: Because of the complex topography in southwest region of China, the water level of the inland river has a large amplitude of variation which causes a frequent diversification of water content in the river slope. The flow caused by the infiltration of the terminal slope stability will induce a great impact on the slope stability of wharf.. This paper uses an ideal elastic-plastic model and the Moore Coulomb yield criterion for numerical simulation. Through the b an k slop e stability of the overhead-type terminal s under the changes of water, we obtained the impact of all factors on the bank slope in the course of water lowering. It was found out that the impact from the cohesion of the geo-materials of the bank slope on the slope stability is greater than that from the internal friction angle.展开更多
基金Supported by the Key Laboratory of Marine Ecology and Environmental Science and Engineering,SOA(No.MESE-2013-01)the National Natural Science Foundation of China(No.41206102)the National Marine Public Welfare Research Project(No.201305009)
文摘We present a GIS-based habitat suitability index(HSI) model to identify suitable areas for Zostera marina L. restoration in the subtidal zone of Xiaoheishan Island. The controlling factors in the model,in order of importance,are Secchi depth,sediment composition,water temperature,salinity,current velocity,water depth and nutrient quality. Specific factor piecewise functions have been used to transform parameter values into normalized quality indexes. The weight of each factor was defined using expert knowledge and the analytic hierarchy process(AHP) method. All of the data thus obtained were interpolated using the inverse distance weighted(IDW) interpolation method to create maps for the entire region. In this study,the analysis of habitat suitability in the subtidal zone of Xiaoheishan Island was conducted for four seasons. According to the GIS-based HSI model,the optimal habitat of Z ostera marina L. appears in spring,although habitat remains suitable all year round. On the whole,the optimum site for eelgrass restoration is located in the eastern region,followed by the western and southern regions. We believe that the GIS-based HSI model could be a promising tool to select sites for Z ostera marina L. restoration and could also be applicable in other types of habitat evaluation.
文摘Containerization with its increasing share in seaborne trade highlights the importance of assessing container terminals performance indicators. The world economical situation and the global container market have improved slightly after the 2008 world economical crises. Egyptian container terminals are important to serve the world liner services in particular the main east-west routes. Egypt is considered the leading country in Africa and the 18th worldwide in serving the liner markets. Alexandria container terminal as a medium size terminal shows an acceptable super/infra structure facilities and throughput. The analysis of Alexandria container terminal performance indicators from 2007 to 2011 shows a slightly progressive trend. Selected indicators, reflecting production, productivity, utilization and service measures, were used according to the available data. Terminal production shows a slight increasing demand concerning number of vessels and TEUs (Twenty Equivalent Units). Furthermore, productivity indicators proved remarkable development in moves per working hours rather than moves per hours in port, deducing lack of port services accompanying cargo handling. Moreover, Utilization measurements show the terminal occupancy ratio fluctuating from 45% to 67% with slight development. Finally, Service measures show progress in vessels turnaround time, while long wasted time consumed in processes rather than operation was observed.
文摘Abstract: Because of the complex topography in southwest region of China, the water level of the inland river has a large amplitude of variation which causes a frequent diversification of water content in the river slope. The flow caused by the infiltration of the terminal slope stability will induce a great impact on the slope stability of wharf.. This paper uses an ideal elastic-plastic model and the Moore Coulomb yield criterion for numerical simulation. Through the b an k slop e stability of the overhead-type terminal s under the changes of water, we obtained the impact of all factors on the bank slope in the course of water lowering. It was found out that the impact from the cohesion of the geo-materials of the bank slope on the slope stability is greater than that from the internal friction angle.