کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5477539 | 1521567 | 2017 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Distribution of natural and anthropogenic radionuclides in northwest Mediterranean coastal sediments
ترجمه فارسی عنوان
توزیع رادیونوکلئید های طبیعی و انسانی در رسوبات ساحلی شمال غربی دریای مدیترانه
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
رسوبات ساحلی، رادیونوکلریدهای آنتروپنی ایزوتوپهای اورانیم، موجودی رسوب، آلودگی جهانی،
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی انرژی
انرژی هسته ای و مهندسی
چکیده انگلیسی
The distribution of radionuclides in NW Mediterranean coastal sediments, and the processes controlling their abundance were investigated in three cores taken near the island of Porquerolles and one offshore Monaco. The sediments collected near Porquerolles were strongly anoxic due to diagenetic processes involved in the decomposition of organic matter, whereas they transitioned from oxic to anoxic at a depth of 4Â cm beneath the seawater interface at Monaco. Organic carbon (OC) was more abundant in sediments at Porquerolles (by about a factor of 3-5) than at Monaco and elsewhere in the coastal NW Mediterranean. Sediment cores collected NE of Porquerolles also possessed elevated uranium concentrations that correlated with high OC content and strong reducing conditions. The 239,240Pu and 241Am activities in surficial sediments ranged from 1 to 5.7 Bq kgâ1 and 0.3 to 1 Bq kgâ1, respectively, while the 137Cs activity ranged from 0.3 to 6.2 Bq kgâ1. The mean activity ratios of 241Am/239,240Pu and 238Pu/239,240Pu in Porquerolles and Monaco sediments were similar to the global fallout ratios. Sediment inventories of global fallout 239,240Pu (430-800 Bq mâ2) and 241Am (150-285 Bq mâ2) were by about a factor of 5-10 higher at Porquerolles, whereas the inventory of 137Cs (430-1000 Bq mâ2) was substantially lower at the investigated stations than have been reported elsewhere at similar latitudes. Specific local conditions characterised by high OC sediment loads due to the growth and mortality of Posidonia oceanica have been responsible for deposition of large amounts of seagrass tissues at the NE corner of Porquerolles, which have had a profound effect on the distribution of radionuclides in the sediments.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Environmental Radioactivity - Volume 172, June 2017, Pages 145-159
Journal: Journal of Environmental Radioactivity - Volume 172, June 2017, Pages 145-159
نویسندگان
Sang-Han Lee, Pavel P. Povinec, John R.M. Chisholm, Isabelle Levy, Juan-Carlos Miquel, Jung-Suk Oh,