@Article{phyton.2016.85.051, AUTHOR = {Espósito ME, MdelC Blanco, ME Sequeira, JD Paoloni, SN Fernández, NM Amiotti,4, SL Díaz}, TITLE = {Natural pollution (As, F) and eutrofication (N, P) in the basin of El Divisorio stream, Argentina}, JOURNAL = {Phyton-International Journal of Experimental Botany}, VOLUME = {85}, YEAR = {2016}, NUMBER = {all}, PAGES = {51--62}, URL = {http://www.techscience.com/phyton/v85nall/37189}, ISSN = {1851-5657}, ABSTRACT = {The interrelation between hydrochemistry and hydrodinamics was analyzed in the basin of El Divisorio stream. This was to gain undestanding in the magnitude, distribution of toxic ions (As, F) and behaviour in the discharge of main nutrients (P, N) contributing to the eutrofication of Paso de las Piedras Dam. During two years, 47 sites were sampled determining several parameters: geographical position for each sampling point, phreatic level depth, and As, F, PO4 and N-NO3 concentrations. Repeated measures, Fisher test, correlation and regression analysis were applied to all variables. Highly significant space and time differences (P<0.01) with increments of 0.3 m were detected for isohypses. At every site, differences with a variable degree of significance were recognized for chemical parameters (As, F, PO4 and N-NO3). Hydrodinamics behaves mainly in accord with the seasonal rainfall contribution; run off affects some of the hydrochemical parameters giving rise to a variability that influences water quality. N-NO3 and PO4 concentrations are the main factors that cause eutrofication expressed through algae bloom episodes and deterioration of stored water quality. P is the critical element and in the dry periods the highest contribution is through groundwater flux and to a lesser extent by the continuous discharge of surface water. In the period of greater runoff, these elements incorporated to the sedimentary charge as a result of soil erosion, and coming by fertilizers and pesticides are transported in suspension towards the reservoir.}, DOI = {10.32604/phyton.2016.85.051} }