The transport and sedimentation of copper in the Glomma estuary, SE Norway during a period of 90% reduction in the industrial input of Cu, was studied from sediment trap material and compared to samples of the bottom sediments. Traps were deployed at four stations for several monthly periods during 1990, 1994 and 1995. Trapped material was analysed for suspended particulate matter (SPM), total organic carbon (TOC) and nitrogen (TN), Cu, and Al. Only about 10% of the Cu from the river is trapped in the estuary. Still there was a moderate but significant reduction in Cu concentration in the trap SPM from 1990 to 1994, reflecting the industrial reductions, but only if excluding summer samples apparently influenced by antifouling Cu from boat paint. Settling matter therefore seems appropriate and sensitive for monitoring changes in the Cu load. The results supported the view that TOC is the main carrier of Cu to the sediments.
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http://dx.doi.org/10.1016/s0025-326x(01)00195-3 | DOI Listing |
Nat Commun
January 2025
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.
Settling aggregates transport organic matter from the ocean surface to the deep sea and seafloor. Though plankton communities impact carbon export, how specific organisms and their interactions affect export efficiency is unknown. Looking at 15 years of eDNA sequences (18S-V4) from settling and sedimented organic matter in the Fram Strait, here we observe that most phylogenetic groups were transferred from pelagic to benthic ecosystems.
View Article and Find Full Text PDFSci Rep
January 2025
Faculty of Veterinary Medicine, University of Khartoum, Khartoum, Sudan.
Schistosomiasis poses a significant global health threat, particularly in tropical and subtropical regions like Sudan. Although numerous epidemiological studies have examined schistosomiasis in Sudan, the genetic diversity of Schistosoma haematobium populations, specifically through analysis of the mtcox1 gene, remains unexplored. This study aimed to investigate the risk factors associated with urogenital schistosomiasis among school pupils in El-Fasher, Western Sudan, as well as the mtcox1 genetic diversity of human S.
View Article and Find Full Text PDFEnviron Int
January 2025
Department of Physics, University of Girona, Campus de Montilivi, Girona 17003 Spain.
Using lock-exchange experiments, this study investigates the transport and sedimentation of microplastics (MPs) via turbidity currents. Two hypotheses were tested: MP sedimentation is influenced by suspended sediment concentration and grain size. Utilizing flows with different sediment concentrations and grain sizes in combination with three different MPs (PET fibers, melamine, and PVC fragments), the experiments revealed distinct sedimentation patterns: higher sediment concentrations enhance MP transport, and turbidity currents with finer sediments transported MPs over greater distances, highlighting the importance of sediment characteristics to predict MP distribution by such flows.
View Article and Find Full Text PDFSci Rep
January 2025
State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian, 116024, China.
This study investigates the critical impact of incipient sediment motion on sediment transport estimation and riverbed evolution prediction. In this research, we examine the effects of ice cover on the vertical distribution of flow velocity, establishing a mathematical relationship between the vertical average flow velocities in open channel and ice-covered flows. This leads to the derivation of a formula for incipient motion velocity under ice cover.
View Article and Find Full Text PDFMar Pollut Bull
January 2025
Department of Ocean Sciences, Inha University, Incheon 22212, Republic of Korea. Electronic address:
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