Selection and grouping of indicators of water quality using Multivariate Statistics
DOI:
https://doi.org/10.5433/1679-0359.2013v34n5p2025Keywords:
Principal component analysis, Cluster analysis, Water quality.Abstract
Multivariate statistics techniques (Principal Component Analysis and Cluster Analysis) were employed to select the most important parameters that explain water quality variability at a rural watershed in the state of Espírito Santo (Brazil). In addition to group the waters studied for the similarity of features selected to verify the effect of type of soil cover (agriculture, livestock, forest and urban), water resource (surface and underground) and sampling period (rainy and dry seasons). Nineteen physico-chemical parameters of water quality were analyzed: pH, electrical conductivity, total solids, total dissolved solids, total suspended solids, turbidity, biochemical oxygen demand (BOD), ammoniacal nitrogen, nitrate, nitrite, total phosphorous, Ca, Mg, Fe, Na, K, Zn, Cu and total coliform. Application of Principal Component Analysis reduced the 19 parameters to three components that explained 87.53% of the total variance of data set. Water quality parameters that best explained variability of data were: electrical conductivity, total solids, total dissolved solids, turbidity, BOD, nitrate, Ca, Mg, and Na. Application of Cluster Analysis showed four different groups of water quality that differed in concentration of physicochemical characteristics and the type of water resource study, since the collection periods and the type of soil cover did not influence the segregation of groups formed.
Downloads
Published
How to Cite
Issue
Section
License
O Copyright dos manuscritos publicados pertence ao periódico. Como são publicados em um periódico de acesso aberto, eles estão disponíveis gratuitamente, para uso privado ou para fins educacionais e não comerciais.
A revista tem o direito de fazer, no documento original, alterações referentes às normas lingüísticas, ortografia e gramática, com o objetivo de garantir as normas padrão do idioma e a credibilidade da revista. No entanto, respeitará o estilo de escrita dos autores.
Quando necessário, alterações conceituais, correções ou sugestões serão encaminhadas aos autores. Nesses casos, o manuscrito deve ser submetido a uma nova avaliação após revisão.
A responsabilidade pelas opiniões expressas nos manuscritos é inteiramente dos autores.