[ Dinámica del fósforo en agua y sedimentos de un embalse subtropical (Salta, Argentina) ]
Volume 6, Issue 2, June 2014, Pages 239–247
María Laura Lamas1 and María Mónica Salusso2
1 Faculty of Natural Sciences, National University of Salta, Avda. Bolivia 5150, (4400), Salta, Argentina
2 Investigation Rede, National University of Salta, Avda. Bolivia 5150, (4400), Salta, Argentina
Original language: Spanish
Copyright © 2014 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
General Belgrano reservoir, in a subtropical region of the province of Salta, is one of the most important in Argentina because of its size and purposes. Previous studies indicate a high speed of increasing its trophic state, adversely affecting the quality of the resource. This paper characterizes the structure (grain size, organic matter content) and amount of phosphorus fractions in sediments, to establish its dynamics during the transition from stratification until mix period. Physical-chemical major variables (temperature, pH, redox potential, conductivity) and phosphorus content (total, reactive soluble and organic) were analyzed according to standardized techniques, at three Secchi depths, interfase and sediment, from March to July, 2011. Water quality in all sites showed high uniformity: it was slightly basic with high conductivity and low concentration of bioavailable phosphorus indicating the extreme mobility of the nutrient in the food chain. The sediments, whose characteristics differed significantly from the overhead compartments, were neutral, with highest conductivity and redox potential values indicating anoxia throughout the study. The tributaries zones have clayey composition, while the lentic area is sandy, which is related to the raised content of phosphorus adsorbed in the first ones. The great amount of phosphorus in sediments demonstrated its relevance as a source of internal eutrophication of the reservoir.
Author Keywords: grain size, physicochemical characteristics, nutrient recycling, phosphate, hydrologic cycle.
Volume 6, Issue 2, June 2014, Pages 239–247
María Laura Lamas1 and María Mónica Salusso2
1 Faculty of Natural Sciences, National University of Salta, Avda. Bolivia 5150, (4400), Salta, Argentina
2 Investigation Rede, National University of Salta, Avda. Bolivia 5150, (4400), Salta, Argentina
Original language: Spanish
Copyright © 2014 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
General Belgrano reservoir, in a subtropical region of the province of Salta, is one of the most important in Argentina because of its size and purposes. Previous studies indicate a high speed of increasing its trophic state, adversely affecting the quality of the resource. This paper characterizes the structure (grain size, organic matter content) and amount of phosphorus fractions in sediments, to establish its dynamics during the transition from stratification until mix period. Physical-chemical major variables (temperature, pH, redox potential, conductivity) and phosphorus content (total, reactive soluble and organic) were analyzed according to standardized techniques, at three Secchi depths, interfase and sediment, from March to July, 2011. Water quality in all sites showed high uniformity: it was slightly basic with high conductivity and low concentration of bioavailable phosphorus indicating the extreme mobility of the nutrient in the food chain. The sediments, whose characteristics differed significantly from the overhead compartments, were neutral, with highest conductivity and redox potential values indicating anoxia throughout the study. The tributaries zones have clayey composition, while the lentic area is sandy, which is related to the raised content of phosphorus adsorbed in the first ones. The great amount of phosphorus in sediments demonstrated its relevance as a source of internal eutrophication of the reservoir.
Author Keywords: grain size, physicochemical characteristics, nutrient recycling, phosphate, hydrologic cycle.
Abstract: (spanish)
El embalse general Belgrano, en la región subtropical de la provincia de Salta, es por sus dimensiones y finalidades, uno de los de mayor relevancia en Argentina. Estudios previos indican que incrementa su estado trófico a altas velocidades, perjudicando la calidad del recurso. El presente trabajo caracteriza la estructura (granulometría, tenor de materia orgánica) y contenido de las fracciones de fósforo en los sedimentos, para establecer su dinámica durante la transición de estratificación hasta el momento de mezcla. Se analizaron las principales variables físico-químicas (temperatura, pH, potencial redox, conductividad) y el contenido de fósforo (total, reactivo soluble y orgánico) a tres profundidades del disco de Secchi, interfase y sedimentos, según técnicas estandarizadas, en tres áreas representativas del embalse, de marzo a julio del 2011. La calidad del agua, en todos los sitios, mostró elevada uniformidad: levemente básica, con alta conductividad y baja concentración de fósforo biodisponible revelando la movilidad extrema del nutriente en la cadena trófica. Los sedimentos, cuyas características se diferenciaron significativamente de los compartimentos superiores, resultaron neutros, con los mayores valores de conductividad y de potencial redox que indican anoxia durante todo el estudio. La granulometría de los ingresos es netamente arcillosa, mientras que en la zona lenítica es arenosa, lo que se relaciona con el mayor contenido de fósforo adsorbido en los primeros. El elevado tenor de fósforo en los sedimentos demuestra su relevancia como fuente de eutrofización interna del embalse.
Author Keywords: Granulometría, Características Físico-Químicas, Reciclado de Nutrientes, Fosfato, Ciclo Hidrológico.
How to Cite this Article
María Laura Lamas and María Mónica Salusso, “Dynamics of phosphorus in water and sediments of a subtropical reservoir (Salta, Argentina),” International Journal of Innovation and Applied Studies, vol. 6, no. 2, pp. 239–247, June 2014.
