Avaliação da distribuição sazonal e espacial dos metais pesados nos sedimentos superficiais do furo da Laura, Amazônia oriental, Brasil.

Abstract

On the present days, one of the biggest ecologic worries is related with the environmental impacts provoked by the natural release and, mainly of anthropogenic chemical compounds, can engender numerous consequences for both environments as for the bodies. The Furo a Laura is the principally water curse from Vigia city (PA), with big extension, daily flow of vessels and marked urbanization on the right border, overflow daily domestic sewer on this estuary, that can deteriorate the quality of the water and sediment. On this way, the objective of the present work is to value the heavy metals of superficial sediments seasonal distribution and spatial from Furo da Laura, Oriental Amazon, qualifying and quantifying the presence or the contamination degree of these elements. For this, the particle size composition were analyzed, the organic matter content and the distribution of the metals Al, Cu, Co, Cd, Cr, Fe, Ni, Mg on the sedimentary layer. The sediments were collected through the using of Ekman-Birge dredger in four locations on Furo da Laura, between September and November of 2001 and, January, March, May and July of 2012. The particular size analyzer were realized by using the shimazu laser equipment, SALD-2201 exemplar, the MO content were obtained by titration and the metals were determined by optical emission spectrometry with induce plasma, (ICP OES), vista-MPX CCD exemplar simultaneous. The Furo da Laura’s sediment was san, predominantly. The organic matter had lower average levels than 10%, being classified as a kind of mineral. Compared to the heavy metals, the sediments demonstrate impacted by Cd, Cr, Ni and Fe. The studded area demonstrate being a streamlined by the seasonal effects, hydrodynamic and Baía do Marajó influence, besides submitted evidences of anthropic contribution of metals from Vigia’s city.