03298nam a2200409 a 450000100080000000500110000800800410001910000190006024500660007926000430014530000110018850000180019952022450021765000170246265000260247965000110250565000120251665000250252865000180255365000130257165000190258465000120260365000270261565000130264265000160265565000260267165300110269765300190270865300210272765300240274865300200277265300240279265300190281665300090283565300200284465300240286415489121994-07-11       1993    bl uuuu  m   00u1 u    #d1 aFELFILI, J. M.  aStructure and dynamics of a gallery forest in Central Brazil.  aOxford, UK: University of Oxfordc1993  a180 f.  aPh.D. Thesis.  aThis is pattern-seeking study in which several features were studied over six years in approximately 64 ha of undisturbed gallery forest alongside the Gama stream. Trees from 31cm gbh (c. 10cm dbh) were measured every three years from 1985 in 151 (10m x 20m) permanent plots. Natural regenerations (individuals under 31 cm ghb) was measured in subplots within the 200 m2 plots. The total tree flora (ghb &gt- 31cm) consisted of 93 species, 81 genera and 44 families in 1985. The Leguminosae, Myrtaceae and Rubiaceae were the richest families in numbers of species. Most individuals and species were under 45cm diameter and 20m whilethe maximum diameter for individual species ranged from 30 to 95cm. The density structure of tree and natural regeneration was similar to each other more than 80% of the species occurring at low densities. The periodic mean annual diameter increment for tree from 10cm dbh, was about 0.25cm/year. Variability was high with coefficients of variation of 100% or more. Niche partitioning seems to determine the density strucure of the forest. The most abundant species occupy different positions in the canopy, have different size structures, spatial distributions and growth habits which enables them to coexist in abundance. The Gama community seems to be robust enough to maintain a diversity of species and structure in undisturbed conditions. Regeneration of about 80% of the species occurred in the estabilishment phase (poles); the diameter structure was typical of a species-rich community with the number of individuals decreasing with increasing size classes and showing little change over the six years; recruitiment compensated for mortality of most of the abundant species. The soils in Gama gallery forest were dystrophic with aluminium contents. Multivariate analyses indicated the stream, natural gap and edges as the main causes of diferentiation at community level. Brief comparisons are made of gallery forests in five sites, sampled by the same methodology, in the same land unit and also whith a forest subjected to repeated burning. Repeated fires degrade gallery forests. The low similarity between sites in the same land unit indicates the need to protect the network of gallery forests.  abiodiversity  abotanical composition  aBrazil  aecology  anatural regeneration  aplant ecology  asavannas  aBiodiversidade  aCerrado  aComposição Botânica  aEcologia  aMata Ciliar  aRegeneração Natural  aBrasil  aCentral region  aDistrito Federal  aFazenda Água Limpa  aFitossociologia  aFloresta de galeria  aGallery forest  aGama  aRegião Central  aRiparian vegetation