Effect of water level on trophic dynamics in a flood plane lake

Abstract

In order to define the trophic interactions in the Caimito swamp complex (municipality of Caimito, department of Sucre 84°7'42.29''N-75°06'48.59''O) and between this and the adjacent ecosystems, the biological communities present were studied. We used the information obtained in previous studies, one in high water period and one in low water period and a sampling of the authors, during the high water period. In each of them, the biotic richness of the body of water and the surrounding environment was studied, the biotic groups were: birds, aquatic macrophytes, aquatic macro invertebrates, fish, zooplankton and reptiles. A list was made of the species and taxonomic groups found, and trophic species were established, which served as the basis for the construction of the food web. The important role of detritus as a source of energy was evidenced in this ecosystem. Most representative groups were the omnivorous fish and the aquatic macro invertebrates, whose broad trophic spectrum and mechanisms for obtaining food make them vital groups in the use of matter and energy and transport to higher trophic levels. The food webs that represent the periods of drought and flood are functionally and structurally different. In period of drought, the community is dependent on detritus and primary producers participate during the flood.