Las cianobacterias como indicadores de contaminación orgánica

• Mariano Peinador ^[1]
  1. [1] Instituto Costarricense de Acueductos y Alcantarillados
• Localización: Revista de Biología Tropical, ISSN 0034-7744, Vol. 47, Nº. 3, 1999, págs. 381-391
• Idioma: español
• Enlaces
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• Resumen
  • español

    En dos ríos de Costa Rica que sirven como cuerpos receptores de aguas residuales domésticas, tratadas mediante lagunas de estabilización, se realizó un total de 28 muestreos en tres puntos de cada río y en las lagunas por un período de cinco años y medio. En cada nuestreo se recolectaron muestras de cinco tipos de sustratos y se cultivó una en dos tipos de medios artificiales. Se observó entre otras cosas, un aumento en la frecuencia de cianobacterias en los lugares con mayor contaminación y una sustitución de especies entre los diferentes lugares.

  • English

    In two Costa Rican rivers used as receptors for domestic sewage, treated by primary stabilization ponds, were taken a total of 28 samplings located at the pond exit and at three different sites in each river: 100 m before the ponds discharge, at the discharge and 100 m after the discharge. These sampling were done for a five and a half years including dry and rainy seasons. In each sampling site, samples were collected of five different substrates: stones, submerge and semi submerge vegetation, tree trunks or sticks, water and artificial substrates. For each sample were used two types of artificial cultures, WC and BG110. A total of 55 cyanobacteria species isolations were obtained, belonging to a 26 genera, between these the most common were Phormidium with nine species, Microcystis with five species, Leptolyngbya and Pseudanabaena with four species each and Oscillatoria with three species. More cyanobacteria species were isolated in water substrate and less isolations in tree trunks and submerge vegetation. Konvophoron, Cyanarcus and Pilgeria only were isolate from water samples inoculated in culture media WC and in few opportunities, while three Leptolyngbya species and four Phormidium species were isolated very often. At the stabilization ponds Phormidium sp4 was dominant in 25 of 28 sampling while in the last others were the chlorophycea I. In this study were observed an increase in the frequency of cyanobacteria at the higher contamination places, and a species substitution between different sampling points. There were no biomass studies, therefore is not possible to relate between different cyanobacteria species and some specific types of water quality.