BIOAVAILABLE FRACTIONS OF ORGANIC MATTER , Cu AND Zn IN SUPERFICIAL SEDIMENTS OF CONCEPCION BAY, CHILE
DOI:
https://doi.org/10.21703/0067-8767.2001.29.2615Keywords:
Sequential Extraction, Metallic Complex, Biolability, Speciation.Abstract
The content oí Cu, Zn and organic matter in different fractions of superficial sediment from the Concepción Bay Chile, was determined. The samples of sedimenta were collected with dredge, stored in the dark and dried at 105 VC for their analysis. The determinations of Cu and Zn were carried out by fíame atomic absorption spectrophotometry and the organic matter was determined by the method of acid oxidación with K2Cr2O7 and calcination at 450vC.In the sequential attack of sediments, four metal- fractions were characterized obtained from each extractive step and the results expressed in mgKg-1 were: the following
results were found: F, Cu 1,57, Zn 3,92 ; F2 Cu 3,37, Zn 37,40 ;F3 Cu not detected, Zn32,26 and F.} Cu35,83, Zn 65,02. Regarding the organic matter content in sediments, two fractions were characterized. The first one corresponded to labile organic matter obtained after moisture oxydation in 24% and the second, highly condensed and refractive organic matter, representing 76 % in the sediment matrix.
