Aquatic insects associated to Eichhornia azurea (Schwartz) Kunth in wetlands of Atrato River, Chocó - Colombia

Abstract

The objective of this study was to characterize the aquatic insect community associated with Eichhornia azurea (Schwartz) Kunth in four swamp of the middle and lower basin of the Atrato river (Chocó-Colombia) during high and low water periods; the influence of environmental and physicochemical variables on this community was also evaluated. For two months, aquatic insects associated with the roots of E. azurea were collected, using a quadrant of one m2, provided with a mesh of 0.5 mm, with three replicates per swamp and simultaneously measured some physical and chemical variables of the water. The community consisted of 6 orders, 21 families and 28 genera. The highest number of organisms (55.39%) and of taxa (23) were recorded in the low water period. The most abundant orders were Ephemeroptera (37.55%) and Coleoptera (26.77%), standing out the families Baetidae and Noteridae respectively; while the greatest taxonomic richness was for Coleoptera, Diptera and Hemiptera. There were no significant differences in diversity and dominance between hydrological periods (p> 0.05), but in the specific richness (p <0.05). The most abundant functional groups were predators (54.81%) and collectors (43.70%). The physicochemical variables did not show significant differences between hydrological periods and there were associations between the aquatic entomofauna and the abiotic variables analyzed, mainly with dissolved oxygen, conductivity and total dissolved solids.

Keywords

• Entomofauna acuática, Eichhornia azurea, planos de inundación, río Atrato.