In February 2004, anthropogenic radionuclides (137Cs, 236U, 239Pu and 240Pu), transported from the Sahara Desert, were observed in the Monaco air, and later in water and sediment samples collected at the DYFAMED site in the northwest (NW) Mediterranean Sea. While 236U and 137Cs in Saharan dust particles showed a high solubility in seawater, Pu isotopes were particle reactive in the water column and in the sediment. The impact of the Saharan deposition was found at 0-1.0 cm of the sediment core for 236U and 137Cs, and between 1.0 and 1.5 cm for Pu isotopes. The excess of 236U was observed more in the water column than in the sediment, whereas the 239+240Pu total inventories were comparable in the water column and the sediment. This single-day particle event represented 72% of annual atmospheric deposition in Monaco. At the DYFAMED site, it accounted for 10% (137Cs) and 15% (239+240Pu) activities of sinking particles during the period of the highest mass flux collected at the 200 and 1000 m water depths, and for a significant proportion of the total annual atmospheric input to the NW Mediterranean Sea (28-37% for 137Cs and 34-45% for 239+240Pu). Contributions to the total 137Cs and 239+240Pu sediment inventories were estimated to be 14% and 8%, respectively. The Saharan dust deposition phenomenon (atmospheric input, water column and sediment) offered a unique case to study origin and accumulation rates of radionuclides in the NW Mediterranean Sea.

中文翻译：

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撒哈拉尘埃事件对西北地中海大气，海水和沉积物中放射性核素的影响。

2004年2月，在摩纳哥的空气中观测到了从撒哈拉沙漠运来的人为放射性核素（137Cs，236U，239Pu和240Pu），后来在西北（NW）地中海的DYFAMED站点收集的水和沉积物样本中被观察到。撒哈拉尘埃颗粒中的236U和137Cs在海水中显示出高溶解度，而Pu同位素在水柱和沉积物中具有颗粒反应性。在236U和137Cs下，撒哈拉沉积的影响在沉积物芯的0-1.0 cm处，而Pu同位素在1.0-1.5 cm之间。在水柱中观察到的236U过量要多于沉积物，而在水柱和沉积物中的239 + 240Pu总库存量是可比的。这次单日颗粒事件占摩纳哥年度大气沉积的72％。在DYFAMED网站上，在200和1000 m的水深处，在收集到的最高质量通量期间，它占下沉粒子的10％（137Cs）和15％（239 + 240Pu）的活动，并占到西北地中海（137Cs占28-37％，239 + 240Pu占34-45％）。估计对137Cs和239 + 240Pu沉积物总量的贡献分别为14％和8％。撒哈拉尘埃沉积现象（大气输入，水柱和沉积物）为研究西北地中海地区放射性核素的起源和积累速率提供了独特的案例。在西北地中海每年的大气总输入量中占很大比例（137Cs占28-37％，239 + 240Pu占34-45％）。估计对137Cs和239 + 240Pu沉积物总量的贡献分别为14％和8％。撒哈拉尘埃沉积现象（大气输入，水柱和沉积物）为研究西北地中海地区放射性核素的起源和积累速率提供了独特的案例。在西北地中海每年的大气总输入量中占很大比例（137Cs占28-37％，239 + 240Pu占34-45％）。估计对137Cs和239 + 240Pu沉积物总量的贡献分别为14％和8％。撒哈拉尘埃沉积现象（大气输入，水柱和沉积物）为研究西北地中海地区放射性核素的起源和积累速率提供了独特的案例。