Composition and floristic structure of two remnants of the Montano Alto Andean Forest in the Ilaló volcano, Ecuador

Abstract

Floristic structure and composition of two High Montane Andean Forest remnants located on the summit of Ilaló volcano (3 190 m) were analyzed. These forest remnants belong to Comunas of San Francisco de Baños–La Merced and Tola Chica. Ten quadrants of 10 × 10 m (0,2 ha) were established in each remnant, and all individuals with DBH ≥ 2,5 cm were measured. A total of 533 individuals were censured and classified in 20 families and 40 species .We observed a clear dominance of Oreopanax ecuadorensis (38,3% in remnant 1 and 42,6% in remnant 2), followed by Vallea stipularis and Geissanthus pichinchae for both remnants. This relationship was also found in the highest values of basal area, where Oreopanax ecuadorensis reached 0,85 and 0,62 m2 , respectively, and in the same way with an IVI of 17% and 19% for each remnant. The Fisher’s alpha, Shannon and Simpson index, used to measure alpha diversity, showed no significant differences for the floristic composition of quadrants. In the same way the NM-MDS (stress = 0,198) and ANOSIM (R = -0,029; p = 0,651) analysis, used to measure beta diversity, showed no significant differences between both remnants, suggesting a continuous historical plant composition. These types of studies are important to know, understand and preserve the remaining vegetation along the Ecuadorian Andes.