Relationship between land use and water quality in a watershed impacted by iron ore tailings and domestic sewage

Laura Pereira do Nascimento, Deyse Almeida Reis, Hubert Mathias Peter Roeser, Aníbal da Fonseca Santiago

Abstract


Changes in land use and land cover in watersheds, together with population increases and urbanization of these areas, have caused negative impacts on surface water quality. Based on land-use types, we conducted a comprehensive water quality study of the Rio do Peixe watershed, a tributary of the Rio Doce River, located in the Iron Quadrangle, with different land uses/land covers. For this study, the relationship between water quality variables and land use types were examined according to the water quality index and principal components analysis. The water samples were collected from twelve stations located along the basin in two different seasons. The results of metals/semimetals concentrations reflected regional lithology, and in the case of iron, it was anthropic activities. Also, the computed water quality index values were between 26.8 and 74.9. The water quality was poor in four stations of the river basin in both seasons. Furthermore, the variables that influence water quality the most were E. coli, DBO, turbidity, nitrate, and total phosphorus. The multivariate statistics gave five principal components that together accounted for 58.3%, whereas analysis of score plots identified the formation of two groups with more perceptible anthropic influence. Finally, environmental impacts of the river basin, such as deforestation, erosion, domestic sewage, and iron ore tailings, were the main factors that interfered with water quality.


Keywords


iron mining, multivariate statistics, Rio Doce



DOI: http://dx.doi.org/10.4136/ambi-agua.2383

Revista Ambiente & Água. ISSN:1980-993X  DOI:10.4136/1980-993X

Patrocinadores:

CAPES  CNPq  MCTI  IPABHi  PPGCA  PRPPG  UNITAU

Filiada à ABEC:

ABEC