Ecological composition of the urban trees of the green areas of La Concordia canton, Santo Domingo de los Tsáchilas, Ecuador

Abstract

Urban trees maintain the dynamics in green areas with the successful establishment of timber and non-timber tree species that provide socio-ecological benefits for the population. Therefore, the research aims to identify the ecological composition of urban trees in the green areas of the urban area of La Concordia. A forest inventory was carried out that included dendrometric information, the identification of botanical families and tree species, as well as the determination of m2 of green areas, the ecological importance value index, Simpson diversity, Shannon-Wiener, Margalef richness, Pielou, Berger-Parker, and Jaccard Foráneo were calculated. The results reported 31 species with 572 individuals, belonging to 16 botanical families, the most representative being La Aracaceae. The canton contains 22 green areas distributed in parks, road safety and green spaces that comprise a total of 357,466 m2 equivalent to 10.08 m2/inhab. The tree community exhibited a greater number of individuals in diameter class II and a lower representation in class XII. Regarding height, class I stood out with a greater presence of small trees, while class IV had a single specimen. The species with the highest index of ecological importance value was Adonidia merrillii Becc 1919, and the lowest was Psidium guajava L. 1753. In terms of diversity, the Simpson index reflected a medium diversity (0.89) and Shannon with high diversity (3.77), Margalef (4.73) reflected an ecosystem with a medium diversity of species, Pielou (0.76) with high equity, Berger-Parker (0.24) a high diversity, the Foráneo identified eight native species and 23 introduced species and, finally, the Jaccard similarity indicated different values between 29.17%, 72% and 73.33% corresponding to three floristic communities. Concluding that the urban trees are young, reflecting a high to medium diversity, however, due to the predominance of introduced species, it is suggested to prioritize the selection of native species for the sustainability of the urban trees.