Data on the total concentrations of phosphorus, calcium, iron and organic matter in surface bed-sediments taken from rivers in the Thames catchment (Wey, Blackwater, Thame and Kennet), the River Swale in Yorkshire (data excludes the organic matter content) as well as the headwaters of the Great Ouse, are collated and compared. Total concentrations of phosphorus, iron and calcium range from 1.7-649, 12-8,333 and 9-4,605 micromol g(-1) (dry weight), respectively, with organic matter in the range of 0.6-19% by dry weight. For the Wey, Blackwater and Great Ouse, sewage inflows had no detectable effect on the sediment concentrations of total calcium, iron and organic matter whereas for the Blackwater and Great Ouse, the total phosphorus contents of the sediment were higher downstream of the effluent input in comparison with a less impacted upstream location. Relationships between the total phosphorus content of the sediments and contents of iron, calcium and organic matter indicated marked differences between the rivers. Although the organic matter content of the sediments was found to be a significant predictor for the total phosphorus concentration for the Blackwater and Great Ouse, the total iron content was also useful for the Blackwater and total calcium for the Great Ouse. It is postulated that this difference is a result of the sediment processes that are known to occur in these two systems, i.e. co-precipitation of phosphate with calcite in the Great Ouse and the formation of vivianite in anoxic sediments of the Blackwater.
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http://dx.doi.org/10.1016/s0048-9697(01)00923-8 | DOI Listing |
Water Res X
May 2025
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
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February 2025
UMR SAS, INRAE, Institut Agro, 35 000 Rennes, France.
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January 2025
Institute of Organic Chemistry, Heidelberg University, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
The design of metalloproteins allows us to better understand metal complexation in proteins and the resulting function. In this study, we incorporated a Cu-binding site into a natural protein domain, the 58 amino acid c-Crk-SH3, to create a miniaturized superoxide dismutase model, termed SO1. The resulting low complexity metalloprotein was characterized for structure and function by circular dichroism and UV spectroscopy as well as EPR spectroscopy and X-ray crystallography.
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January 2025
Department of Soil Science, Faculty of Agriculture/ Institute for Agricultural Research, Ahmadu Bello University, Zaria, Nigeria.
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