Mechanisms of Trace Metal Transport in Rivers

Abstract

Trace metals transported by the Amazon (and Yukon rivers were analytically partitioned among the transport phases: in solutions, ion exchange, organic materials, metallic coatings, and crystalline solids. The distribution for both rivers is similarly proportioned, with copper and chromium transported mainly in the crystalline solids, manganese in coatings, and iron, nickel, and cobalt distributed equally between precipitated metallic coatings and crystalline solids.

The low-temperature geochemical cycle of iron: From continental fluxes to marine sediment deposition

“…These procedures commonly provide a measure of the metals associated with five phases (adsorbed, associated with oxyhydroxides, organic matter or carbonates, or present in residual silicate minerals). However, organic matter, carbonate and adsorbed phases tend to be relatively insignificant in terms of the total transport of iron (Gibbs, 1973(Gibbs, , 1977Trefry and Presley, 1982;Zhang and others, 1990;Baruah and others, 1996). Thus we have adopted a three stage extraction procedure for our river particulates, based on techniques used to determine the speciation of iron in marine sediments (see Berner, 1970;Canfield, 1989;Raiswell and others, 1994).…”

Association of trace metals with various sedimentary phases in dam reservoirs

“…Chemical partitioning studies were also conducted. The following four steps were implemented: 1) Acetic acid 25 %v/v, 2) Acetic acid 25 % v/v-0.1 M hydroxylamine hydrochloride, 3) 30 % H 2 O 2 , and 4) Hot 50 % HCl (Gibs, 1973). To assure the accuracy of the results, all containers used for laboratory works were soaked in dilute HNO 3 overnight and rinsed with distilled water prior to use.…”

Water quality of streams draining abandoned and reclaimed mined lands in the Kantishna Hills area, Denali National Park and Preserve, Alaska, 2008–11

“…The concentration of organic carbon in sediment is an indicator of the amount of organic matter. The capacity of organic matter to concentrate some trace elements in stream sediment is well recognized (Gibbs, 1973;Horowitz, 1991), and this capacity varies with the type of organic matter. For the Kantishna Hills sites, organic carbon concentrations were less than 1 percent only at the two Moose Creek sites (table 12) and the corresponding mean PEC quotients were less than 0.5.…”