| 摘要: |
| 作者采用浊度计和声学多普勒流速剖面仪(ADCP)在近海区域连续、定点观测的应用中, 利用浊度与悬沙浓度之间良好的线性关系, 对潮汐半月周期内的浊度和ADCP后向散射声强数据进行相关性分析, 讨论了小、中、大潮期间利用ADCP后向散射声强反演悬沙浓度的可靠性, 反演过程中综合考虑了声学近场非球面扩散和本底噪声的影响。结果表明, 在实验海域中, 小潮情况下, 各水层内悬浮泥沙成分较为稳定, ADCP后向散射声强与浊度变化相关性较高, 达到0.91; 而在大潮情况下, ADCP后向散射声强与浊度变化的相关性降低, 悬沙浓度及成分容易在海流的影响下发生变化。 |
| 关键词: 声学多普勒流速剖面仪 浊度 悬沙浓度 后向散射声强 |
| DOI：10.11759//hykx20150217001 |
| 分类号: |
| 基金项目:国家自然科学基金项目(61505221): 中国科学院战略性先导科技专项(XDA11040306) |
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| Reliability analysis of suspended sediment concentration estimated using an ADCP and a turbidity meter |
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LI Xiao-long,CHEN Yong-hua,JIANG Jing-bo,NI Zuo-tao,LIU Qing-kui,XU Yong-ping,TU Deng-zhi,LI Si-ren
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| Abstract: |
| Turbidity and suspended sediment concentration (SSC) exhibit a good linear relationship, while the relationship between the intensity of acoustic backscatter (ABS) and SSC shows a monotonic increase. In this paper, at an offshore continuous observation fixed-point, an acoustic Doppler current profiler (ADCP) was used to estimate the SSC. Turbidity and ADCP echo intensity values were collected during a tidal cycle over half a month and analyzed by correlation. The reliability of an SSC inversion model using acoustic backscatter intensity was discussed for neap and spring tides. The SSC inversion process took into account the impact of nonspherical spreading in the near field of the acoustic transducer as well as background noise. Here the analysis of the data from these field experiments showed that during the spring tide, the concentration and composition of the suspended sediments were affected by tidal ranges and currents. In other words, the particle size of the suspended sediment changed dramatically during the spring tide, which impacted the SSC and ABS correlation. However, during the neap tide, the particle size distribution of the suspended sediment remained stable. Therefore, SSC can be determined using ADCP acoustic backscatter. |
| Key words: ADCP turbidity suspended sediment concentration acoustic backscatter |
