A comparison of geochemical information obtained from two fluvial bed sediment fractions |
| |
| Authors: | Ross A Sutherland |
| |
| Institution: | (1) University of Hawaii, Geomorphology Laboratory, Department of Geography, 2424 Maile Way, Honolulu, Hawaii 96822, USA e-mail: Sutherla@Hawaii.edu, US |
| |
| Abstract: | A total of 121 bed sediment samples were collected from a 5.8-km stretch of Manoa Stream, Hawaii. Samples were physically
partitioned into two grain-size fractions, <63 μm and 63–125 μm, acid digested and analyzed by ICP-AES and FAAS. Non-parametric
matched-pair statistical testing and correlation analysis were used to assess differences and strengths of association between
the two fractions for Al, Ba, Cu, Fe, Mn, Ni, Pb, Ti and Zn. Results indicated statistically significant differences between
fractions for all elements except Mn. Concentrations were significantly greater in the <63 μm fraction for Al, Cu, Pb, Ti
and Zn, while Ba, Fe and Ni were higher in the 63–125 μm fraction. Though some elements had statistically significant differences
between fractions (Al, Ba, Fe and Zn) percentage differences were in the range of analytical precision of the instrument and
thus differences were not practically significant. Correlation analysis indicated strong positive associations for all elements
between the two fractions (p<0.0001). Three contamination indices indicated similar degrees of pollution for each size fraction
for four elements having an anthropogenic signal (Ba, Cu, Pb and Zn). The environmental information obtained from the 63–125 μm
fraction was essentially equivalent to that from the <63 μm fraction. In this system it is clear that both bed sediment fractions
indicate anthropogenic enrichment of trace metals, especially Pb, and further supports previous research that has found that
aquatic sediments are critical median for tracing sources of pollution.
Received: 17 August 1998 · Accepted: 30 October 1998 |
| |
| Keywords: | Fluvial bed sediments Contamination indices Grain-size partitioning Non-parametric statistics Manoa Stream |
| 本文献已被 SpringerLink 等数据库收录！ |
|
