Resumen

CHALIMOND, María Laura; FERREYRA, Marina  y  COSSAVELLA, Ana María. Measurement of sediment oxygen demand rates for benthic demand of Tercero (Ctalamochita) River, Córdoba province, Argentina. Tecnol. cienc. agua [online]. 2019, vol.10, n.2, pp.241-259.  Epub 21-Abr-2021. ISSN 2007-2422.  https://doi.org/10.24850/j-tyca-2019-02-09.

Modeling of dissolved oxygen technique in rivers is a valuable tool for assessing water quality. Hence, assessment of different processes is of great importance, like benthic demand, that is to say, oxygen consumption of the water column in the water-sediment interface. At the moment there are no previous studies related to this field for the Tercero (Ctalamochita) River (Córdoba, Argentina). This study aimed to measure the benthic demand of Tercero (Ctalamochita) River from sediment samples that were taken at eight sites in five campaigns during one year (June, 2013 to June, 2014), using individual respirometers. Taking into account the variation of the dissolved oxygen as regards time, water volume, sediment area and characteristics of respirometers, benthic demand was estimated using the equation of Nolan and Johnson, (1979) proposed by the USEPA. Since there is no previous data, it was impossible to compare the acquired results. However, the range values found at 20 °C was between 0.040 and 0.484 gO2/m2d, being similar to those reported by the USEPA for mineral and sandy river sediments (0.05-1.00 gO2/m2d). These results allow us to understand the behavior of benthic sediment and its influence on the dissolved oxygen.

Palabras llave : Sediment oxygen demand; individual respirometers; dissolved oxygen; Tercero (Ctalamochita) River.