Filters: partyWithName: Ishiga, Hiroaki (X)
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The aim of this study was to determine if Arase dam gate removal and flushing elevated concentrations of any trace elements in Kuma River and Yatsushiro Bay sediments or caused riverine environmental change. The Arase dam gate on the Kuma River was opened in April 2010. Surface and bottom sediments were compared using 10-cm-long cores (2011) and two grain size fractions. Surface sediment data from 2002, 2012, and 2013 from the Kuma River and Yatsushiro Bay were also compared. The sediments were analyzed using XRF for 23 elements, and the grain size analysis was done. The short core surface and bottom sediments do not show major chemical changes, and therefore, may not represent post-and pre-dam sediments. Results...
Categories: Publication;
Types: Citation;
Tags: Bays,
Chemical,
Environmental Monitoring,
Geologic Sediments,
Japan,
Chemical composition of 24 elements for sed- iments and suspended solids, water parameters and the diatoms from Yatsushiro Bay tidal flat, Kuma River, and Arase Dam have been determined to examine changes from 2002 to 2013. In 2002, sediment delivered to the bay by the Kuma River was restricted by the Arase Dam; however, in April 2010 two gates were opened and also repeated sea- sonal flushing allowing resumption of natural sediment transport. Bulk chemical composition of the tidal flat sed- iments has changed since 2002, with marked decreases in concentrations of As, Zn, Pb and total sulfur. Decreased heavy metal contents in 2012 and 2013 for bay sediments after opening the dam and repeated flushing is attributed...
Categories: Publication;
Types: Citation;
Tags: Arase Dam,
ENRICHMENT,
HEAVY-METALS,
IRON,
Kuma River,
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