Assessment of the water self-purification capacity on a river affected by organic pollution: application of chemometrics in spatial and temporal variations

Abstract

Water pollution caused by organic matter is a major global problem which requires continuous evaluation. Multivariate statistical analysis was applied to assess spatial and temporal changes caused by natural and anthropogenic phenomena along Potrero de los Funes River. Cluster analysis (CA), principal component analysis (PCA) and analysis of variance (ANOVA) were applied to a data set collected throughout a period of 3 years (2010-2012), which monitored 22 physical, chemical and biological parameters. Content of dissolved oxygen in water and biochemical oxygen demand in a watercourse are indicators of pollution caused by organic matter. For this reason, the Streeter-Phelps model was used to evaluate the water self-purification capacity. Hierarchical cluster analysis grouped the sampling sites based on the similarity of water quality characteristics. PCA resulted in two latent factors explaining 75.2 and 17.6 % of the total variance in water quality data sets. Multidimensional ANOVA suggested that organic pollution is mainly due to domestic wastewater run-offs and anthropogenic influence as a consequence of increasing urbanization and tourist influx over the last years. Besides, Streeter-Phelps parameters showed a low reaeration capacity before dam with low concentration of dissolved oxygen. Furthermore, self-purification capacity loss was correlated with the decrease of the Benthic Index. This measurement suggested that biological samplings complement the physical-chemical analysis of water quality.

Experimenting biochemical oxygen demand decay rates of Malaysian river water in a laboratory flume

“…Depuration comprises different mechanisms such as dilution, sedimentation, reaeration, adsorption, absorption, and chemical and biological reactions, and can be evaluated by the same mathematical model (Bahadur et al, 2013, González et al, 2014. Water quality models are essential tools for the development of planning and management measures for water resources in river basins (Panagopoulos et al, 2012).…”

Spatio-Temporal Variations and Source Apportionment of Water Pollution in Danjiangkou Reservoir Basin, Central China

“…More and more attention has been paid to surface water quality, as it is strongly relevant to human lives and public health [1,2]. However, as surface water quality is controlled by both natural factors (hydrological and meteorological conditions) and human influences (urban, industrial and agricultural activities), decision makers are facing with significant difficulties the problem of how to manage surface water quality [3][4][5].…”

Determination of Spatiotemporal Variations in Heavy Metal Concentration through Orontes River

“…It is observed that most parameters especially As, Cr, Cu, Pb, Zn and Mn have a high standard deviation and a high change interval. This situation indicates that heavy metal concentration varies depending on anthropogenic and natural factors (González et al, 2014). Mean concentration of Fe, Mn and Zn was chancing between 353-594 µg/L, 63-353 µg/L and 30-50 µg/L, respectively.…”