RESUMO
Background: Loss of biological connectivity increases the vulnerability of ecological dynamics, thereby affecting processes such as pollination. Therefore, it is important to understand the roles of the actors that participate in these interaction networks. Nonetheless, there is a significant oversight regarding the main actors in the pollination networks within the highly biodiverse forests of Colombia. Hence, the present study aims to evaluate the interaction patterns of a network of potential pollinators that inhabit an Andean Forest in Totoró, Cauca, Colombia. Methods: The interactions between plants and potential pollinators were recorded through direct observation in 10 transects during six field trips conducted over the course of one year. Subsequently, an interaction matrix was developed, and network metrics such as connectance, specialization, nestedness, and asymmetry of interaction strength were evaluated by applying null models. An interpolation/extrapolation curve was calculated in order to assess the representativeness of the sample. Finally, the key species of the network were identified by considering degree (k), centrality, and betweenness centrality. Results: A total of 53 plant species and 52 potential pollinator species (including insects and birds) were recorded, with a sample coverage of 88.5%. Connectance (C = 0.19) and specialization (H2' = 0.19) were low, indicating a generalist network. Freziera canescens, Gaiadendron punctatum, Persea mutisii, Bombus rubicundus, Heliangelus exortis, Chironomus sp., and Metallura tyrianthina were identified as the key species that contribute to a more cohesive network structure. Discussion: The present study characterized the structure of the plant-pollinator network in a highly diverse Andean forest in Colombia. It is evident that insects are the largest group of pollinators; however, it is interesting to note that birds form a different module that specializes in pollinating a specific group of plants. On the other hand, the diversity and generality of the species found suggest that the network may be robust against chains of extinction. Nevertheless, the presence of certain introduced species, such as Apis mellifera, and the rapid changes in vegetation cover may affect the dynamics of this mutualistic network. So, it is imperative to apply restoration and conservation strategies to these ecosystems in order to enhance plant-animal interactions and prevent the loss of taxonomical and functional diversity.
Assuntos
Ecossistema , Florestas , Animais , Colômbia , Polinização , Insetos , Plantas , AvesRESUMO
Se caracterizó la estructura y composición florística del remanente boscoso ubicado en la Reserva Forestal de la Institución Educativa Cajete, Popayán (Cauca). El inventario florístico se hizo mediante colecta libre realizada en el interior y la periferia del bosque. Se registraron en total 164 especies, 130 géneros y 58 familias. En Magnoliophyta se registraron 142 especies, 112 géneros y 44 familias; las familias más diversas fueron Asteraceae (31 especies y 26 géneros) y Araceae (10 especies y 3 géneros). En Lycophyta y Monylophyta se reconocieron 22 especies, 18 géneros y 14 familias; siendo Polypodiaceae con 4 especies la familia con mayor riqueza. Para determinar la estructura se muestrearon todos los individuos con DAP ≥ 1 cm en 10 bandas de 50 x 2 m, hallándose 560 individuos de plantas vasculares pertenecientes a 39 especies, 33 géneros y 25 familias. El bosque presentó 3 estratos: herbáceo, arbustivo y arbóreo. El estrato arbustivo fue el dominante con un elevado número de especies; el estrato arbóreo estuvo constituido por unas pocas especies. Quercus humboldtii y Banara guianensis fueron las especies con mayor dominancia e índice de valor de importancia en el bosque.
The floristic structure and composition of the remaining wooded area located in the Cajete Educational institution forest reserve in Popayan (Cauca) was studied. The floristic inventory was performed through free collection carried out inside and in the periphery of the forest. In total 164 species, 130 genera and 58 families were recorded. In Magnoliophyta 142 species belonging to 112 genera and 44 families were recorded, being Asteraceae (31 species and 26 genera) and Araceae (10 species and 3 genera) the most diverse families. In Monylophyta and Lycophyta 22 species belonging to 18 genera and 14 families were recognized, being Polypodiaceae with 4 species, the family with more richness. To determine the structure all individuals were sampled with ≥ 1 cm DAP in 10 bands of 50 x 2 m, and in total 560 individuals of vascular plants belonging to 39 species, 33 genera and 25 families were found. The forest presented three different strata: herbaceous, shrubby and arboreal. The shrubby stratum was dominant with a high number of species whereas the arboreal stratum consisted only of a few species. Quercus humboldtii and Banara guianensis were the species with greater dominance and with high importance value index in the forest.
