Evaluation of the Influence of Natural and Antrhopogenic Processes on Water Quality in Karstic Region

• Published in: Water, air, and soil pollution Vol. 223; no. 5; pp. 2157 - 2168
• Main Authors: Calijuri, Maria Lúcia, do Couto, Eduardo de Aguiar, Santiago, Aníbal da Fonseca, Camargo, Rodrigo de Arruda, e Silva, Marcos D. F. M.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-06-2012; Springer; Springer Nature B.V
• Subjects: Airport expansion; Airports; Analysis; Aquatic resources; Aquifers; Atmospheric Protection/Air Quality Control/Air Pollution; Climate Change/Climate Change Impacts; Cluster analysis; Contamination; Dynamical systems; Dynamics; Earth and Environmental Science; Environment; Environmental impact; Environmental monitoring; Groundwater; Groundwater data; Groundwater pollution; Hydrogeology; Integrated approach; Karstic areas; Karstic environments; Microorganisms; Multivariate analysis; Population growth; Precipitation; Principal components analysis; Sensitivity analysis; Soil permeability; Soil Science & Conservation; Statistical analysis; Statistical methods; Studies; Surface chemistry; Surface water; Surface-groundwater relations; Urban sprawl; Water quality; Water Quality/Water Pollution; Water resources; Water, Underground; Watershed management; Karstic environments; Karst of Lagoa Santa; Pollution; Surface and groundwater quality; Multivariate statistics
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-011-1012-5

This paper presents a comprehensive study on the quality of surface and groundwater in an environmentally sensitive karstic watershed strongly pressed by urban growth. The objective of the study was to assess the integrated effects of human activities and natural characteristics of karstic environments on the quality of surface and groundwater using multivariate statistical techniques. Data from 18 physical, chemical, and microbiological water quality variables obtained throughout a hydrological year were analyzed using principal components analysis (PCA) and cluster analysis. The PCA was carried out individually for surface water and groundwater. Our goal was to study the behavior of the water quality variables at each of these systems, as well as to infer the importance of these variables on the dynamics of the water resources in the region. Our results for surface water showed that the 18 original variables could be reduced to five principal components which together accounted for 69% of the total variation in the data, whereas for groundwater, 70% of the total variation in the data was explained by five principal components. In order to evaluate the impacts of anthropic activities on the water quality at the monitoring locations, the cluster analysis was applied to the ten sampling points. The analysis identified five clusters, two of which are formed by points with low contamination levels and three where the anthropic interference is noticeable. The results suggest the existence of specific contamination sources in many points, including in the groundwater, and highlight the natural vulnerability of the karstic environments.