Global fallout Pu isotopes, 137Cs and 237Np records in the sediments of Lake Xingkai and their response to environmental changes in the catchment

Sequential Extraction of 239+240Pu and the Vertical Distribution of 239+240Pu, 137Cs, and Heavy Metals in Chang-Bai Mountains’ Grassland Soil

“…65 The activities of 239+240 Pu and 137 Cs in the surface sediments of the Lake Xingkai near the Chang-Bai Mountains were 0.524 and 13.6 mBq/g, respectively. 66 Besides, the 239+240 Pu activities in the area between Semipalatinsk and Lop Nor, which with a similar latitude to this study area ranged from 0.035 to 1.338 mBq/g. 67 At 40−50°N, the 137 Cs activities were in the range of 1.91−50.0 mBq/g.…”

Radionuclide 239+240Pu for Dating and Sedimentation Rate in Chinese Lakes

“…The peak position of 239+240 Pu in the middle layer is the most common type in sediment core samples in China (Table S1), as shown in the XK08 core, FX core, and 2006QH-1. 18,19,27 Meanwhile, the vertical structure in the HF20040709S core is obviously different from the first two types; this study detected the peak position of 239+240 Pu in the deeper layer around 30− 40 cm depth. 15 It is worth mentioning that the HF20040709S sediment core sample is located in Lake Hongfeng, which is a man-made lake (reservoir) with water storage from the early 1960s.…”

“…To the best of our knowledge, this study has summarized all the available published references in Chinese lakes (Table , Figure , and Table S1) and found 24 sediment cores to study 239+240 Pu inventory. ,,− The 239+240 Pu inventory in the lake sediment core is calculated following eq below. I = prefix∑ i = 1 n ( B i × C i × D i ) where I is the inventory (Bq m –2 ) of 239+240 Pu in the lake sediment core as shown in eq , n is the number of subsampled layers, i is the number of subsampling layers of the lake sediment core, B i is the dry density of the i -th layer sediment core (g cm –3 ), C i is the 239+240 Pu activity in the i -th layer of the sediment core (mBq g –1 ), and D i is the thickness of the i -th layer (cm).…”

“…Furthermore, the feasibility of using the convection dispersion equation (hereafter, CDE) model to study the migration rate or apparent convection velocity of 239+240 Pu in a lake sediment core needs to be further discussed. 25,27 The focus of this work is to study the vertical distribution of 239+240 Pu in sediment core samples collected in Chinese lakes (and lakes outside China). We propose to (1) systematically investigate the vertical distribution characterization of 239+240 Pu in lake sediment cores based on all the publicly available sediment core sample data in China; (2) examine the relationship between sedimentation rates (v, 239+240 Pu peak) and the maximum depths of the 239+240 Pu peak based on statistical analysis; and (3) understand the source and inventory of 239+240 Pu in the lake sediment core samples in China.…”

Studi Koefisien Distribusi 137Cs di Perairan Muara Cisadane, Teluk Jakarta

“…Tingkat radioaktivitas 137 Cs pada sedimen di Perairan Muara Cisadane adalah 0,60-1,22 Bq.kg -1 dengan rata-rata 0,842 Bq.kg -1 . Nilai tersebut lebih rendah dibandingakan nilai aktivitas 137 Cs dengan beberapa penelitian sebelumnya seperti di sekitar perairan muara sungai Xingkai, China yang terdeteksi nilai aktivitasnya sebesar 6,4-30,1 Bq.kg -1 (Zhang et al, 2022), di Laut Baltic terdeteksi sebesar 22,6-66,7 Bq.kg -1 dan di dekat FDNPP sekitar 29,6-34,7 Bq.kg -1 (Song et al, 2020). Tingkat radioaktivitas di pesisir Indonesia memiliki nilai 0,33-0,83 Bq.kg -1 (Suseno dan Prihatiningsih, 2014) dan pada pesisir Barat Sumatera memiliki nilai rendah pula yaitu sekitar 0,016-0,334 Bq.kg -1 (Makmur et al, 2020).…”