| 摘要: |
| 悬浮颗粒物粒径分布通常可用幂律模型来描述。本文基于2014年11月黄、渤海的现场悬浮颗粒物粒径数据，研究了幂律模型在黄、渤海的适用性；同时，参考粒径作为幂律模型的重要参数，影响着幂律模型的斜率（颗粒粒径分布斜率）和模拟精度，因此对不同参考粒径下幂律模型的斜率变化情况以及模型模拟精度也进行了分析。结果显示：黄、渤海区域颗粒粒径分布斜率在0.46~7.53（均值：4.09），其中84.2%的斜率在3.2~4.5范围内；当参考粒径小于7.33 μm时，颗粒粒径分布斜率变化大（均值为5.60±1.09），颗粒粒径分布模拟误差大，平均相对误差绝对值在20%~85%范围内，平均相对误差绝对值的平均值为48.2%；当参考粒径为7.33~19.8 μm时，颗粒粒径分布斜率为4.08±0.29，颗粒粒径分布模拟的平均相对误差绝对值在5%~25%范围内，平均相对误差绝对值的平均值为9.8%；当参考粒径大于19.8 μm时，颗粒粒径分布斜率为3.87±0.25，颗粒粒径分布模拟的平均相对误差绝对值在2%~10%范围内，平均相对误差绝对值的平均值为6.0%。误差分析表明：参考粒径取值大于19.8 μm，幂律模型对颗粒粒径分布的模拟效果较好，最优参考粒径可选为122.0 μm，此时模拟误差最小（平均相对误差绝对值的平均值为4.79%±1.78%）。 |
| 关键词: 黄渤海 悬浮颗粒物 颗粒粒径分布 幂律模型 参考粒径 LISST-100 |
| DOI： |
| 分类号:P733.3 |
| 基金项目:国家自然科学基金项目(41276186)；“全球变化与海气相互作用”专项(GASI03030101)；南京信息工程大学人才启动基金(2243141501007)；江苏高校优势学科建设工程资助项目（PAPD）；国家海洋公益性行业专项项目(201005030) |
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| The study of suspended particulate matters particle size distribution based on the power-law model--- A case study in the Yellow Sea and Bohai Sea |
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PengTian,Qiu Zhong-feng,Sun De-yong and Wang Sheng-qiang
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Nanjing University of Information Science and Technology,Nanjing University of Information Science and Technology,Nanjing University of Information Science and Technology,Nanjing University of Information Science and Technology
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| Abstract: |
| Suspended particulate matters particle size distribution (PSD) have been found to most often follow the power law size distribution. In this study, we examined the applicability of the power law for simulating the particle size distribution (PSD) of the suspended particles in the Yellow Sea and Bohai Sea, based on LISST-100 measurements during November 2014. The reference diameter, an important parameter of the power law model, affects the PSD power-law slope and the PSD simulation accuracy. The influence of different reference diameter on PSD power-law slope and the PSD simulation accuracy are analyzed. Results showed that most power-law fitted PSD slopes ranged from 0.46 to 7.53; and 84.2% of values are within the range of 3.20-4.50(mean：4.09). Changes of the reference diameter (D0) have significant influence on the PSD slope and PSD simulation accuracy: when D0<7.33 μm, significant changes，PSD slopes ranged from 0.46 to 7.53（mean =5.60, standard deviation =1.09)and large errors(the mean absolute percentage errors(MAPE):20-85%, mean MAPE:48.2%) were observed in the PSD slope and the PSD simulation, respectively; when 7.33 μm 19.8 μm, the PSD slope 3.87±0.25，the PSD simulation error is minimum( MAPE:2-10%, mean MAPE:6.0%). Through error analysis, the reference diameter selection greater than 19.8 μm, the PSD simulation results are fitted well. The optimal reference diameter can be chosen as 122.0 μm, which the simulation error is minimum (mean MAPE is 4.79%±1.78%) . |
| Key words: The Yellow Sea and Bohai Sea Suspended particulate matter Particle size distribution Power-law model Reference diameter LISST-100 instrument |