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This research evaluated the oxygen transfer efficiency in beds to be used as aerated constructed wetlands. The research methods included oxygen transfer efficiency evaluations in several bed configurations using diffused aeration systems. Experiments were conducted at two locations with different environmental conditions: a) Talca (Chile), 120 m above sea level (m.a.s.l.), 0.99 Atm and b) Cajicá (Colombia), 2550 m.a.s.l., 0.76 Atm. A column with only clean water and three bed configurations representing aerated constructed wetlands were evaluated. These configurations included: (a) coarse gravel, (b) coarse gravel with an empty core in the middle (inner container), and (c) fine gravel. Three airflow rates were evaluated: (a) low, 0.7 L/min; (b) medium, 2.5 L/min; and (c) high, 3.6 L/min. The overall oxygen mass transfer coefficient, standard oxygen transfer rate, and standard oxygen transfer efficiency were the variables calculated from the oxygen transfer evaluation tests. The research results indicated that in diffused aeration systems, oxygen transfer efficiency was negatively influenced by environmental conditions, particularly altitude, which limits the driving force for oxygen transfer into water. Furthermore, the results showed that the size of the gravel used in the bed is related to the oxygen transfer efficiency: the larger the gravel size, the higher the oxygen transfer, regardless of the altitude. Finally, research regarding oxygen transfer in aerated constructed wetlands has signaled the need for a standard procedure for aeration testing, and this work suggests a new methodology.

El presente artículo es una propuesta metodológica para la valoración de los aspectos sociales dentro de la Evaluación del Uso de la Tierra. Se tomaron como referencia las características de las Unidades de Tierra Jaraquiel y Nariño, localizadas en el Valle del río Sinú y establecidas como tales en Estudio Básico para un Plan de Ocupación del Espacio2, realizado por el IGAC en el año 1987. La presente metodología es una propuesta preliminar, que deberá ser enriquecida y ajustada en la medida en que se aplique a casos reales o se consideren otras perspectivas no tenidas en cuenta aquí.