US EPA

3786690 

Journal Article 

In-site Measurement for Relationship among Grain Size Distribution of Suspended Solid and Bottom Sediment and Particulate Total Mercury in Minamata Bay, Japan 

Yano, S; Hisano, A; Riogilang, H; Kawase, H; Tai, A; Matsuyama, A; Tada, A; Yano, K; Huang, Wei; Zhaoyin, W; Lee, JHW; Jizhang, G; Shuyou, C 

2013 

No 

Tsinghua Univ 

BEIJING 

PROCEEDINGS OF THE 35TH IAHR WORLD CONGRESS, VOLS III AND IV 

English 

WOS:000370410301020 

Mercury in sea water can be transported by advection and diffusion/dispersion processes, and there are exchange processes between air and sea water and one between bottom sediment and sea water. Both of methylmercury and inorganic mercury can exist as both of particulate form and dissolved one in water. Since particulate mercury may attach with suspended solids (SS) in water, the distribution can depend on resuspention and settling of bottom sediments. Thus, in the recent development of numerical model for mercury transport and its fate combination of hydrodynamic model, which can solve the physical oceanographic process such as a flow and a sediment transport, with biogeochemical model to solve methylation-demethylation equilibrium for mercury has been studying. Since 2006, our research group has been conducting monthly monitoring of mercury concentration in sea water in the Minamata Bay, Japan. In 2010 we introduced LISST-100X which can measure in-situ grain size distribution of SS into monthly water sampling. In the present paper, we report these measurement results. In addition, core sampling for bottom sediment was conducted three times in 2010, 2011 and 2012. As a result, the followings were clarified: i) There is significant difference of SS grain size distribution between upper layer and lower one in density stratification; ii) Origin of SS in upper layer can be estimated to exist in except for bottom sediment and load from rivers; and iii) Characteristics of correlation between particulate T-Hg and SS grain size distribution are obvious. 

Particulate total mercury; Grain size distribution; Bottom sediment; LISST-100X; Suspended solids 

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