Floristic composition, structure and endemism of vegetation fragments in southern Ecuador

Abstract

The Andean vegetation in Ecuador is diverse, very vulnerable to environmental and anthropic changes, and can be differentiated as ascending or descending in altitude. The objective of this research was to determine the structure and floristic composition of vegetation along an altitudinal gradient from 2500 to 2850. In the forest, six 20 x 20 m plots were installed for trees, three 5 x 5 m subplots for shrubs, and five 1 x 1 m subplots for herbs. In the scrubland, six 5 × 5 m plots were installed, and two 1 × 1 m plots were nested for herbs. Six 2 × 2 m plots were installed on the moorland. Individuals larger than 5 cm D1.30 m were measured, and shrubs and herbs were recorded. Floristic composition, diversity, endemism, and structural parameters were determined, including density, frequency, dominance, and IVI. The floristic composition was compared using Sorensen's index. In the forest, 109 species of 86 genera and 50 families were recorded; in the scrubland, 46 species of 41 genera and 22 families were recorded; and in the moor, 45 species, 36 genera, and 24 families were recorded. Fourteen endemic species were identified. The species with the highest IVI were Morella pubescens and Viburnum triphyllum in the forest, Miconia lutescens and Gaultheria reticulata in the scrub, and Orthrosanthus chimboracensis and Calamagrostis intermedia in the moorland. The floristic composition of the vegetation covers investigated was different, with high floristic diversity and endemism, despite anthropic intervention, and their conservation should be sought.

Keywords: Diversity, Montane forest, Villonaco, Altitudinal gradient, Loja, Plant succession, forest conservation.