Las aguas de la subcuenca Zanjón Oscuro (Departamento del Cauca), son utilizadas para regar caña de azúcar, mediante el uso de drenajes artificiales. En su recorrido el cauce recibe aguas residuales domésticas e industriales de la población y la industria azucarera, lo cual ha originado la contaminación del mismo. Se presenta la evaluación de la calidad del agua mediante la elaboración de un índice de calidad del agua “ICA”, a partir del uso de la Estadística Aplicada. Se propone el uso de una metodología basada en curvas de calidad de diferentes parámetros fisicoquímicos desarrollados a partir de encuestas realizadas a varios expertos, con el objeto de establecer límites cualitativos y cuantitativos de la calidad del agua; para posteriormente seleccionar la curva óptima que refleje la mejor decisión, en dicha evaluación. Los resultados fueron comparados con los indicadores de contaminación del agua (ICOMO). Finalmente se obtuvieron dos indicadores: el primero conformado por las variables oxígeno disuelto, demanda bioquímica de oxígeno y coliformes fecales, que son indicadores de la contaminación por materia orgánica. El segundo indicador incluye la demanda bioquímica de oxígeno, pH, conductividad, fosfatos, nitratos, turbiedad y sólidos totales, que permiten una evaluación general de la calidad del agua.

The waters of the subriver basin Zanjón Oscuro, located in the plains of northern Cauca, Cauca Department, are used for irrigation of sugar cane by the use of artificial drainages. In its course the stream receives domestic and industrial sewage from the population and the sugar industry, which has led to pollution of it. This paper presents the work the evaluation of the quality of the water by means of the elaboration of water quality index “WQI”, from the use of the Applied Statistic. For this aim the use of a methodology based on the elaboration of curves of quality of different physico-chemical parameters sets out that they were developed from a realised survey to different experts, with the intention of establishing qualitative and quantitative limits of the quality of the water; later to select the optimal curve that reflects the best decision to evaluate the quality of the water. The results were compared with the indicators of contamination of the water. Obtaining like result two indicators, the first conformed by the variables dissolved oxygen, biochemical demand of oxygen and faecal coliforms, which are indicating of the contamination by organic matter. The second includes the biochemical demand of oxygen, pH, conductivity, phosphates, nitrates, turbidity and total solids, which allow a general evaluation of the quality of the water.

Se recolectaron aves pertenecientes a 69 especies y 25 familias en el parque nacional natural Sierra de La Macarena (Colombia), de junio a noviembre del año 2000, y se examinaron para hematozoarios. Ochenta y dos de las 342 aves (24%) fueron positivos para uno o más hematozoarios. En los preparados sanguíneos de aves positivas, las microfilarias fueron los parásitos más comunes (10,5%), y Leucocytozoon el mas escaso (0,3%). Otros parásitos observados pertenecieron a los géneros de Plasmodium (4,4%), Trypanosoma (3,5%), Hepatozoon (3,5%) y Haemoproteus (3,2%). Las bajas intensidades de parásitos hemosporidianos están de acuerdo con otros registros en el neotrópico. La prevalencia de parásitos en esta región es mayor que los niveles encontrados en otros estudios en la región neotropical, pero menores que los niveles encontrados para el área neártica. Nosotros reportamos aquí nuevas asociaciones parásito-hospedero, también como especies aviares examinadas por primera vez para hematozoarios.

Birds from 69 species in 25 families were collected from La Macarena National Natural Park in Colombia between June and November 2000 and examined for haematozoa. Eighty-two of the 342 birds (24%) were positive for one or more taxon. Microfilariae were the most commonly seen parasites (10.5%) and Leucocytozoon the least common (0.3%). Other parasites were species of the genera Plasmodium (4.4%), Trypanosoma (3.5%), Hepatozoon (3.5%) and Haemoproteus (3.2%). The low intensity of haemosporidian parasites agreed with other records from the Neotropics. Parasite prevalence in this Neotropical region was higher than levels found in other surveys in the Neotropics, but lower than levels found for the Nearctic area. A new host-parasite association is reported here, as well as avian species examined for haematozoa for the first time.

Blood samples from 159 birds of the New-world family Tyrannidae (the flycatchers) from the eastern plains of Colombia, were examined for haematozoa parasites, in 1999-2000. Haematozoa were detected in six of 20 species. The overall prevalence was 10.1%. The most common parasites detected were microfilariae, followed by Trypanosoma and Plasmodium. The highest prevalence (9.6%) was found in the Ochre-bellied Flycatcher (Mionectes oleaginea). Mixed infections with more than one genus of blood parasite were rare and most infections encountered were of low intensity. The results of this study suggest an important role of ecologically diverse conditions determining composition, transmission, and prevalence of a blood parasite fauna, presumably through host interaction population density. Some new host parasite relationship records are presented.