Preliminary Results of a Large-Scale Tree Inventory of Upland Rain Forest in the Central Amazon

Abstract

A large-scale inventory of trees > 10cm DBH was conducted in the upland "terra firme" rain forest of the Distrito Agropecuário da SUFRAMA (Manaus Free Zone Authority Agricul tural District) approximately 65Km north of the city of Manaus (AM), Srasil. The general appearance and structure of the forest is described together with local topography and soil texture. The preliminary results of the Inventory provide a minimum estimate of 698 tree species in 53 families in the 40Km radius sampled, including 17 undescribed species. The most numeri cally abundant families, Lecythidaceae, Leguminosae, 5apotaceae and Burseraceae as also among the most species rich families. One aspect of this diverse assemblage is the proliferation of species within certain genera, Including 26 genera In 17 families with 6 or more species or morphospecies. Most species have very low abundances of less than 1 tree per hectare. While more abundant species do exist at densities ranging up to a mean of 12 trees per ha, many have clumped distributions leading to great variation in local species abundance. The degree of similarity between hectare samples based int the Coefficient of Community similarity Index varies widely over different sample hectares for five ecologically different families. Soil texture apparently plays a significant role In determining species composition in the different one hectare plots examined while results for other variable were less consistent. Greater differences in similarity indices are found for comparisons with a one hectare sample within the same formation approximately 40Km to the south. It is concluded that homogeneity of tree commu nity composition within this single large and diverse yet continuous upland forest formation can not be assumed.

Metapopulation Extinction Thresholds in Rain Forest Remnants

“…1). The continuous forest at BDFFP consists of nonflooded tropical lowland rain forest ranging from 50 to 150 m in elevation (Bierregaard et al 1992) and is characterized by a complex canopy architecture of trees 30-40 m tall with emergents reaching up to 55 m (Rankin-de-Merona et al 1992).…”

Response of tree biomass and wood litter to disturbance in a Central Amazon forest

“…Work was carried out on permanent plots monitored since the early 1980s by the biomass and nutrient experiment (BIONTE) logging experiment (Higuchi et al 1997) of the National Institute for Amazon Research (Instituto Nacional de Pesquisa da Amazonia, (INPA)) and the biological dynamics of forest fragments project (BDFFP), a collaboration between INPA and the Smithsonian Institution (Lovejoy and Bierregaard 1990;Rankin-De Merona 1992;Laurance et al 2002). Data obtained from the permanent plots included stand dynamics (i.e., free recruitment, growth and mortality rates), and taxonomic information for trees >10 cm trunk base diameter (D\,; measured 1.3 m or above the buttresses), hereafter referred to as "trees."…”

Ecosystem decay of Amazonian forest fragments: implications for conservation

“…Results from the BDFFP suggest that such sample effects could be especially important for Amazonian species, which often have patchy distributions at varying spatial scales and complex patterns of endemism (e.g., Zimmerman and Bierregaard 1986, Vasconcelos 1988, Allmon 1991, Rankin-de Merona et al 1992, Souza and Brown 1994, Didham et al 1998a, Laurance et al 1998a, Peres 2005. Pronounced clumping means many species will be missing from any particular fragment or reserve simply because they never occurred there in the first place.…”