The composition of Amazonian forests: Patterns at local and regional scales
Journal of Tropical Ecology
1998
Journal Article
14
645-664
Parque Nacional del Manu detrended correspondence analysis floodplains floristic composition multi-dimensional scaling terra firme Brazil Costa Rica diversity vegetation dynamics ecology Parque Nacional del Manu Los Amigos Cocha Cashu Diamante Pakitza trees habitats large spatial scales Moraceae Euphorbiaceae Arecaceae palms plants Fabaceae Myristicaceae Lecythidaceae Chrysobalanaceae Madre de Dios Bibliography
An analysis was conducted of floristic patterns contained in 48 1-ha tree plots distributed at 29 sites in seven neotropical countries, with a primary emphasis on the Amazonian region. Analyses were made with family level data, using detrended correspondence analysis and multidimensional scaling to generate two-dimensional ordinations. Dissimilarity values for all pairs of plots were then used to compare forest composition at both local (flooded vs unflooded forests) and regional scales (e.g., western vs central vs eastern Amazonia). The predominate family of trees in a large majority of Amazonian and Guianan forests (by number of stems) is either Palmae or Leguminosae (sensu latu), followed by Moraceae and Euphorbiaceae. The forests of western Amazonia are particularly rich in palms, Moraceae, and Myristicaceae, whereas those of eastern Amazonia and the Guianas are rich in Lecythidaceae and Chrysobalanaceae. Dissimilarity between sites increases with distance for both flooded and unflooded forests. The tree communities of flooded and unflooded forests within a region tended to resemble one another more closely than forests of either type resembled the homologous forests of the adjoining regions. Within Amazonia the edaphic properties of each region and its geological history are tightly interrelated. it is therefore difficult to distinguish between evolutionary and ecological interpretations of the results.