Comparative analysis of chemical and bacterial distribution of coastal lagoons and freshwater lakes in Turkish Thrace

Abstract

Análisis comparativo de la distribución química y bacteriana de lagunas costeras y lagos de agua dulce en la Tracia Turca ABSTRACT Background. Microbial contamination of water bodies is causing major environmental and public health concerns in developing countries. Bacterial inclusion of inland waters can be of allochthonous and/or autochthonous origins. Goals. The aim of this study was to determine and compare the microbial contamination with environmental factors controlling colonization of bacteria in lagoon-lakes and freshwater lakes. Methods. Two lagoon-lakes and two freshwater lakes in Turkish Thrace were chosen and sampling was undertaken from October 2014 to August 2015 at seasonal intervals. While total heterotrophic bacteria, E. coli, coliform, and fecal coliform bacteria distributions from allochthonous and autochthonous origins were determined, environmental conditions of the ecosystems were also measured. While the Bray-Curtis Similarity Index and the Correspondence Analysis with Abundance Plot Analyses were used to determine the similarities of the sampling habitats, the Spearman's Correlation Index was applied to clarify relationships between the environmental variables and the bacterial distribution. Results. The bacterial distribution was positively related to dissolved oxygen in one of the sampled lagoon-lakes (r = 1.0, p < 0.01) and negatively correlated with total dissolved solids and salinity in one of the sampled freshwater lakes (r = -0.95, p < 0.01; r = -0.80, p < 0.05, respectively). Conclusions. This research indicated that the saline water of the lagoon-lakes has limited the number of bacteria when compared with freshwater lakes.