A DR300 Broad Band ADCP mounted on a vessel moving at a speed of 2-3 m/s was used to measure the profile of suspended sediment concentrations (SSCs) at the entrance to Jiaozhou Bay, Shandong Peninsula, where the water...A DR300 Broad Band ADCP mounted on a vessel moving at a speed of 2-3 m/s was used to measure the profile of suspended sediment concentrations (SSCs) at the entrance to Jiaozhou Bay, Shandong Peninsula, where the water is characterized by low SSCs. The echo intensity data produced by the ADCP were regressed against the SSCs derived using the filtration method. The results show that the calibrated relationship can be used to calculate the SSC, with a relative error of 30%. Therefore, it is feasible to measure the SSC (even if the concentration is low) using the ADCP mounted on a moving vessel. Compared with OBS, ABS and other instruments for SSC measurements, the ADCP represents a potentially powerful tool to retrieve SSC data in continental shelf waters.展开更多
The purpose of the present contribution is to explore the technique to use Acoustic Doppler Current Pro- filers （ADCPs） for suspended sediment flux measurements, which may be applied to coastal embayment environment...The purpose of the present contribution is to explore the technique to use Acoustic Doppler Current Pro- filers （ADCPs） for suspended sediment flux measurements, which may be applied to coastal embayment environments such as estuaries and tidal inlets for sediment exchange and budget studies. Based on tidal cycle measurements from the entrance of ]iaozhou Bay, Shandong Peninsula, eastern China, statistical rela- tionships between the suspended sediment concentration （SSC） and ADCP echo intensity output are estab- lished. Echo intensity data obtained during an ADCP survey along two cross-sections during a spring tidal phase were transformed into SSC data. The ADCP current velocity and SSC data were then used to calculate the flux of fine-grained sediment. The results show that net sediment transport at the entrance is directed towards the open sea, with an order of magnitude of 103 t per spring tidal cycle; hence, although Jiaozhou Bay is a low SSC environment, the tidally induced suspended sediment transport can be intense.展开更多
A Nortek acoustic Doppler current profiler (NDP) was installed on a moving vessel to survey the entrance to the Jinhae Bay on August 22~23, 2001. The current velocity and acoustic backscattering signal were collected ...A Nortek acoustic Doppler current profiler (NDP) was installed on a moving vessel to survey the entrance to the Jinhae Bay on August 22~23, 2001. The current velocity and acoustic backscattering signal were collected along two cross-sections; water samples were also collected during the measurement. The acoustic signals were normalized to compensate for the loss incurred by acoustic beam spreading in the seawater. The in situ calibration shows that a significant relationship is present between suspended sediment concentrations (SSC) and normalized acoustic signals. Two acoustic parameters have been determined to construct an acoustic-concentration model. Using this derived model, the SSC patterns along the surveyed cross-sections were obtained by the conversion of acoustic data. Using the current velocity and SSC data, the flux of suspended sediment was estimated. It indicates that the sediment transport into the bay through the entrance has an order of magnitude of 100 t per tidal cycle.展开更多
文摘A DR300 Broad Band ADCP mounted on a vessel moving at a speed of 2-3 m/s was used to measure the profile of suspended sediment concentrations (SSCs) at the entrance to Jiaozhou Bay, Shandong Peninsula, where the water is characterized by low SSCs. The echo intensity data produced by the ADCP were regressed against the SSCs derived using the filtration method. The results show that the calibrated relationship can be used to calculate the SSC, with a relative error of 30%. Therefore, it is feasible to measure the SSC (even if the concentration is low) using the ADCP mounted on a moving vessel. Compared with OBS, ABS and other instruments for SSC measurements, the ADCP represents a potentially powerful tool to retrieve SSC data in continental shelf waters.
基金A project of the Mega-Science Program supported by the Ministry of Science and Technology of China:"Land-ocean boundary processes and their impacts on the formation of the Yangtze deposition system" under contract No.2013CB956500a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The purpose of the present contribution is to explore the technique to use Acoustic Doppler Current Pro- filers （ADCPs） for suspended sediment flux measurements, which may be applied to coastal embayment environments such as estuaries and tidal inlets for sediment exchange and budget studies. Based on tidal cycle measurements from the entrance of ]iaozhou Bay, Shandong Peninsula, eastern China, statistical rela- tionships between the suspended sediment concentration （SSC） and ADCP echo intensity output are estab- lished. Echo intensity data obtained during an ADCP survey along two cross-sections during a spring tidal phase were transformed into SSC data. The ADCP current velocity and SSC data were then used to calculate the flux of fine-grained sediment. The results show that net sediment transport at the entrance is directed towards the open sea, with an order of magnitude of 103 t per spring tidal cycle; hence, although Jiaozhou Bay is a low SSC environment, the tidally induced suspended sediment transport can be intense.
文摘A Nortek acoustic Doppler current profiler (NDP) was installed on a moving vessel to survey the entrance to the Jinhae Bay on August 22~23, 2001. The current velocity and acoustic backscattering signal were collected along two cross-sections; water samples were also collected during the measurement. The acoustic signals were normalized to compensate for the loss incurred by acoustic beam spreading in the seawater. The in situ calibration shows that a significant relationship is present between suspended sediment concentrations (SSC) and normalized acoustic signals. Two acoustic parameters have been determined to construct an acoustic-concentration model. Using this derived model, the SSC patterns along the surveyed cross-sections were obtained by the conversion of acoustic data. Using the current velocity and SSC data, the flux of suspended sediment was estimated. It indicates that the sediment transport into the bay through the entrance has an order of magnitude of 100 t per tidal cycle.
