Dredging plume dispersion studies, use dredging plume models to predict the fate of sediment plumes resulting from dredging activities and dredge spoil disposal. The model results are applied as input to environmental...Dredging plume dispersion studies, use dredging plume models to predict the fate of sediment plumes resulting from dredging activities and dredge spoil disposal. The model results are applied as input to environmental impact assessment of the proposed dredging, particularly those associated with suspended sediments and sedimentation. Model validation and performance are still not resolved because of the difficulty of site measurements and the understanding of the parameters used in the model. This paper presents a 3-D dredging plume model based on the MIKE3 software package to investigate parameters which affect the model performances. As a result of lack of site data for the public domain uses, the model scenarios are designed artificially for sensitive runs to identify the key parameters affecting plume behaviours. The factors include dredging spill rates using different dredging methods, equipment and sediment settling velocities. The influence of wave and wind effects combined with tidal forces on the sediment re-suspended rates and the advection/dispersion scales are also assessed.展开更多
This research investigates the impact of cyclone Sidr on six regional economic systems of Bangladesh. The study uses secondary data on direct damages and corresponding changes in consumer spending and public/private i...This research investigates the impact of cyclone Sidr on six regional economic systems of Bangladesh. The study uses secondary data on direct damages and corresponding changes in consumer spending and public/private investment expenditure. It employs input–output modeling and simulates the changes in national and regional output,income, and employment due to cyclone Sidr. Our findings indicate that coastal regions of Bangladesh—Barisal,Chittagong, and Khulna—are more vulnerable to cyclone disaster than are other parts of the country. The cycloneinduced loss of output is highest for Chittagong Division and income and employment losses are greatest in Barisal Division. The most affected sectors are housing services,agriculture, construction, and industrial activities. But sectoral losses vary widely across the regions. This research also finds that the present state of consumer spending and investment expenditure is not great enough to handle cyclone-induced output, income, and employment losses. It argues that investment decisions must consider regional patterns of output, income, and employment losses in different economic sectors to ensure cyclone-resilient development in Bangladesh.展开更多
文摘Dredging plume dispersion studies, use dredging plume models to predict the fate of sediment plumes resulting from dredging activities and dredge spoil disposal. The model results are applied as input to environmental impact assessment of the proposed dredging, particularly those associated with suspended sediments and sedimentation. Model validation and performance are still not resolved because of the difficulty of site measurements and the understanding of the parameters used in the model. This paper presents a 3-D dredging plume model based on the MIKE3 software package to investigate parameters which affect the model performances. As a result of lack of site data for the public domain uses, the model scenarios are designed artificially for sensitive runs to identify the key parameters affecting plume behaviours. The factors include dredging spill rates using different dredging methods, equipment and sediment settling velocities. The influence of wave and wind effects combined with tidal forces on the sediment re-suspended rates and the advection/dispersion scales are also assessed.
基金the Climate Change Trust FundMinistry of Environment and Forest, Government of the People’s Republic of Bangladesh for funding this research
文摘This research investigates the impact of cyclone Sidr on six regional economic systems of Bangladesh. The study uses secondary data on direct damages and corresponding changes in consumer spending and public/private investment expenditure. It employs input–output modeling and simulates the changes in national and regional output,income, and employment due to cyclone Sidr. Our findings indicate that coastal regions of Bangladesh—Barisal,Chittagong, and Khulna—are more vulnerable to cyclone disaster than are other parts of the country. The cycloneinduced loss of output is highest for Chittagong Division and income and employment losses are greatest in Barisal Division. The most affected sectors are housing services,agriculture, construction, and industrial activities. But sectoral losses vary widely across the regions. This research also finds that the present state of consumer spending and investment expenditure is not great enough to handle cyclone-induced output, income, and employment losses. It argues that investment decisions must consider regional patterns of output, income, and employment losses in different economic sectors to ensure cyclone-resilient development in Bangladesh.
