Variación florística de especies arbóreas a escala local en un bosque de tierra firme en la Amazonia colombiana

Abstract

El presente estudio se llevó a cabo en cinco hectáreas de una parcela permanente establecida en el Parque Nacional Amacayacu, Amazonia colombiana. En éste, se evaluó el efecto de la variación ambiental y la configuración espacial sobre los patrones florísticos de las especies arbóreas (DAP>10 cm) a escala local en un bosque de tierra firme. Se estudió la variación florística y ambiental en cuadrantes de 20x20 m. Adicionalmente, se consideraron diferentes categorías de abundancia (total, alta, media y baja). Se utilizó el Análisis de Correspondencia Linealizado y el Análisis de Correspondencia Canónica, seguido de una partición de la variación, para cuantificar la magnitud a la cual el ambiente y la limitación en dispersión determinan la variación florística. La fracción espacial, representando procesos de autocorrelación como la limitación en dispersión, se analizó mediante dos métodos: Asumiendo un polinomio de tercer grado y por el método de Coordenadas Principales de Matrices Vecinas (PCNM). La diversidad beta de la parcela fue baja. El PCNM aparece como el método de análisis más apropiado para estudios a esta escala. Las diferencias florísticas explicadas a lo largo de la parcela de 5-ha fueron principalmente asociadas con procesos biológicos como la limitación en dispersión. La mayor parte de la variación florística, no obstante, no fue explicada por las variables ambientales o espaciales consideradas. En conclusión, estos resultados sugieren que procesos aleatorios son determinantes esenciales de la variación espacial de las especies arbóreas a escala local en tierra firme en los bosques en el Parque Nacional Amacayacu.

Forest Diversity and Structure in the Amazonian Mountain Ranges of Southeastern Ecuador

“…Finally, Sollins, in 1998, [63] states that the availability of phosphorus, potassium, calcium, and magnesium significantly influences the composition of species in lowland rainforests, although by integrating other factors such as soil drainage and topography (pending relatively pronounced in the forests of Terra Firme and flat relief in the Tepuy forests in our study) make it necessary to incorporate other factors to understand the distribution of plant wealth. Similar results have been reported in Amazonian forests, where calcium and aluminum have shown a high correlation with species distribution patterns at the regional and local scales, however, microhabitat variability, related to soil heterogeneity, are responsible for the presence of certain species throughout the forest, a factor that we mentioned as important in the determination of groups of plants or types of forest in our study [9,55,58,64,65].…”

“…In forests similar to those studied here, Huamantupa 2009 [41] found that the five most abundant species were Iriartea deltoidea (Arecaceae), Pseudolmedia laevis (Moraceae), Otoba glycycarpa (Myristicaceae), Astrocaryum murumuru (Arecaceae), and Leonia glycicarpa (Violaceae). Other studies in Amazonian forests of Ecuador, Peru, and Colombia mentioned Lecythidaceae, Myristicaceae, Arecaceae, and Moraceae as dominating this type of ecosystem [9,12,19,42].…”

“…In recent decades, the forests of the Ecuadorian Amazon have undergone high rates of deforestation and fragmentation [5], which modifies environmental conditions at local and regional levels (higher temperatures, changes in precipitation regimes, and increased CO 2 concentrations). These ecosystems are home to one of the highest concentrations of vascular plant species [6], but most studies are limited to the floristic diversity of these ecosystems [7,8], without relating this richness and diversity to environmental, geomorphological factors, and soil [9], nor with altitude patterns and specific edaphic-environmental factors such as precipitation, seasonality, soil fertility, and topography [10][11][12]. Others noted that climatic variables (for example, the amount of annual rainfall) are not good estimators of wealth [13].…”

Importância fitossociológica de um fragmento de floresta ombrófila densa no estado de Roraima, Brasil

“…Foram encontradas 15 "espécies raras" ou "localmente raras" (33%), ou seja, espécies que ocorrem com apenas um indivíduo por hectare (SILVA et al, 2010;KUNZ et al, 2014). Estudos na região amazônica demonstram que existe grande quantidade de espécies raras, geralmente perfazendo entre 30 e 55% da comunidade total em um hectare (SILVA et al, 1992;ALMEIDA et al, 1993;MUNIZ et al, 1994;OLIVEIRA e AMARAL, 2004).…”

Ecological quality of a forest in a state of succession based on structural parameters: A case study in an evergreen Amazonian-Andean forest, Ecuador

“…Lastly, the ASDP was rated 3 when no disturbance indicator species were reported in the evergreen forest area, 2 if one to three were present and 1 if there were more than three disturbance indicator species. The lowest value of ASDP was assigned to estimate the scarce impact that ecological succession has had on species richness in the community ( Benítez-Malvido and Martínez-Ramos, 2003 ; Patiño et al., 2015 ; Silva et al., 2010 ; Villa et al., 2019 ). The maximum score for the four structural parameters (3) corresponded to the desired state for the ecological structure of the evergreen Amazonian-Andean forest of the Puyo River micro-basin and the lowest score (1) when alterations and disruption in the ecological structure occurred.…”