Factors controlling dissolved 137Cs concentrations in east Japanese Rivers
Factors controlling dissolved 137Cs concentrations in east Japanese Rivers
复制标题
日本东部河流溶解 137Cs 浓度的控制因素
DOI:
10.1016/j.scitotenv.2019.134093
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发表时间:
2019
影响因子:
9.8
通讯作者:
Hayashi Seiji
中科院分区:
文献类型:
--
作者:
Tsuji Hideki;Ishii Yumiko;Shin Moono;Taniguchi Keisuke;Arai Hirotsugu;Kurihara Momo;Yasutaka Tetsuo;Kuramoto Takayuki;Nakanishi Takahiro;Lee Sangyoon;Shinano Takuro;Onda Yuichi;Hayashi Seiji
To investigate the main factors that control the dissolved radiocesium concentration in river water in the area affected by the Fukushima Daiichi nuclear power plant accident, the correlations between the dissolved137Cs concentrations at 66 sites normalized to the average137Cs inventories for the watersheds with the land use, soil components, topography, and water quality factors were assessed. We found that the topographic wetness index is significantly and positively correlated with the normalized dissolved137Cs concentration. Similar positive correlations have been found for European rivers because wetland areas with boggy organic soils that weakly retain137Cs are mainly found on plains. However, for small Japanese river watersheds, the building area ratio in the watershed strongly affected the dissolved137Cs concentration. One reason for this would be because the high concentrations of solutes, such as K+and dissolved organic carbon, discharged in urban areas would inhibit137Cs absorption to soil particles. A multiple regression equation was constructed to predict the normalized dissolved137Cs concentration with the topography, land use, soil component, and water quality data as explanatory variables. The best model had the building land use as the primary predictor. When comparing two multiple regression models in which the explanatory variables were limited to (1) the land use and soil composition and (2) the water quality, the water quality model underestimated the high normalized dissolve137Cs concentration in urban areas. This poor reproducibility indicates that the dissolved137Cs concentration value in urban areas cannot be solely explained by the solid-liquid distribution of137Cs owing to the influence of the water quality, but some specific137Cs sources in urban areas would control the dissolved137Cs concentration.