The aquatic plants of Lagartococha's Lacustrine-riverine system, at the reserve for faunistic breeding of Cuyabeno, Ecuador

Abstract

An assessment of floristic assemblage of aquatic vascular plants was carried out in the Lagartococha riverine system of the Reserva de Producción Faunística Cuyabeno (RPFC) in the Amazon basin of Ecuador. The aims of the study were to determine the structure and composition of aquatic vegetation within riparian environments, aimed to recognize conservation targets for monitoring programs and identify the species habitat preferences applying non parametric statistic analysis. Twenty eight transects were established across the riverine system, located over different types of vegetation. The similarities in aquatic plants distribution were analysed with Jaccard Index, while the similarities of cover patterns were analysed by Steinhaus Index. The changing patterns of environment conditions in the sampling places were correlated by a Principal Component Analysis. Three kinds of vegetation were determined: gramalote, dominant in lotic environments; mandial, growing only in Delfincocha and Imuya lakes and riparian vegetation spread along the most lentic environments (lakes). Twenty eight aquatic vascular plants were recorded including amphibians and submersed life forms. Only five species have widespread distribution across the river system and three species were restricted to one kind of environment. Four life forms were recorded: the rooted floating plants, which are dominants (43% of the overallspecies), the emergent rooted plants (32%), the free floating plants (14%) and the submersed rooted plants(11%). According with the species richness and the different kinds of vegetation which are growing in Delfincocha and Imuya lakes is necessary to consider those environments as a priority target of conservation in the area. Moreover in those environments there are a few populations of Cabomba furcata Schult. & Schult.f. (Cabombaceae), Hydrocotyle ranunculoides L. f. (Apiaceae) y Najas arguta Kunth (Najadacae) that are likely unique records for this riparian system.