Mirlean Nicolai, Calliari Lauro, Baisch Paulo, Loitzenbauer Ester, Shumilin Evgueni
Laboratory of Marine Geology, Department of Geosciences, Fundação Universidade do Rio Grande, CP 474, Rio Grande, RS 96200-900, Brazil.
Environ Monit Assess. 2009 Oct;157(1-4):583-9. doi: 10.1007/s10661-008-0558-1. Epub 2008 Oct 2.
The distribution of mercury in sediments of the Patos Lagoon estuary and nearby coastal marine deposits has been investigated for the period 1998-2008. Polluted urban soils and coastal reclamation fills are the principal sources of high mercury concentrations for shallow estuarine sediments. The shallow sediments that form near the urban area enter the navigation canal and are transported into the ocean. The mercury concentration in sediments of the navigation canal has considerably increased since 2004, due to intense reconstruction activity in the urban area. Periodic dredging of the canal strengthens the preconditions for coastal marine sediment contamination by mercury. However, this does not occur because the resuspended dredged sediments are significantly diluted by natural suspended particulate matter.
1998年至2008年期间，对帕图斯泻湖河口及附近沿海海洋沉积物中的汞分布进行了调查。受污染的城市土壤和沿海填海造地是浅海河口沉积物中高汞浓度的主要来源。城市附近形成的浅层沉积物进入通航运河并被输送到海洋中。自2004年以来，由于城市地区的高强度重建活动，通航运河沉积物中的汞浓度大幅增加。运河的定期疏浚强化了沿海海洋沉积物被汞污染的前提条件。然而，这种情况并未发生，因为疏浚后重新悬浮的沉积物被天然悬浮颗粒物显著稀释了。
