Dynamics of epiphytic algae assemblage in ayapel flood plain through flood pulse Dinámica del ensamblaje algal epifítico en el sistema de planos inundables de ayapel a través del pulso de inundación

Abstract

Spatial and temporal variations of the epiphytic algae assemblages associated with roots of macrophytes in 14 sampling sites, seven zones with lentic and seven with lotic conditions of the Ayapel flood plain was evaluated. It was determined that the degree of connectivity between the river, the streams and swamp increased in high waters which produced physico-chemical uniformity conditions and limited the development local conditions. Thus, the most isolated bodies reach a greater degree of independence from the main body due to the formation of horizontal gradients. This individualization of the physico-chemical conditions is most evident in the low water phase. Diversity and richness of species variation at the spatial level was found, as well as lower floristic similarity (30%) between the periphytics assemblages which favored the recorded high species richness. Diatoms predominated in the system, being favored by ammonium concentration; their abundance decreased with precipitation increase. Chlorophyceae are favored by the precipitation increase, variation in water level, low concentrations of nitrates, nitrogen ammoniacal and electrical conductivity. Low concentrations of nutrients and the decrease of precipitation favor the development of the cyanobacteria. Finally, Euglenophyceae, Dynophyceae and Chrysophyceae are considered as minority algal groups within the epiphytic assembly.