Ecological Characterization of the Flora in Reserva Ecológica Arenillas, Ecuador

Abstract

Ecuador, located in the Neotropics, has 66 protected natural areas, which represent about 13.77% of its overall territory. The Reserva Ecológica Arenillas reserve (REAr), located in southwestern Ecuador, protects an area of dry forest, coastal thorn forest, and mangroves. This dry forest is part of the Pacific equatorial core and is included the Tumbes–Chocó–Magdalena, one of the 34 biodiversity hot spots of the world. It is an extremely fragile ecosystem and therefore the need for conservation is of the utmost importance. Knowledge of the flora and their ecological characteristics is still limited, which was one of the main objectives of this work. In this study, 118 plots located in different locations of the REAr were selected in order to sample the trees, shrubs, and herbaceous plants within them. This information was supplemented with data from the literature and the GBIF; life forms were included according to Raunkiaer’s classification and their growth habits. The flora of the REAr was represented by 381 species, belonging to 77 families. The two most numerous families were the Fabaceae (51 plant species) and Malvaceae (31 species). The dominant life form was the phanerophytes with 200 species (52.5%), followed by therophytes with 104 species (27.3%), and camephytes with 22 species (5.8%). Physiognomy was dominated by the herbaceous growth (44%). The biodiversity indices of two ecosystems were studied (The deciduous forest of the Jama-Zapotillo lowland and the low forest and deciduous shrubland of the Jama-Zapotillo lowland), obtaining higher values for the deciduous forest ecosystem of the Jama-Zapotillo lowland. With these indicators, a classification of each forest type was made by performing a hierarchical cluster analysis. The information provided in this paper is particularly important for focusing conservation efforts and preventing the loss of flora diversity in these forests, which are subject to great anthropogenic pressures.

Keywords

• biodiversity
• floristic composition
• tropical dry forest
• species diversity