The Role of Density Dependence in the Population Dynamics of a Tropical Palm

Abstract

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Contemporary and historic factors influence differently genetic differentiation and diversity in a tropical palm

“…Moreover, it is possible that habitat loss and fragmentation have not yet reduced the population size to a point that markedly changes the processes maintaining genetic diversity (Kramer et al, 2008). E. edulis occur in swampy areas and in high densities in fragment remnants (Matos et al, 1999). Indeed, we observed historical constant population sizes for all sites.…”

Effects of density on the vital rates of a modular seaweed

“…The demography of A. nodosum in the stochastic environment of Swedish shores has been assessed by model simulations (Åberg 1992b). The simulations did not explicitly include density-dependent regulation and it has, in general, seldom been incorporated into demographic models of macroalgae and other perennial plants such as trees (see Burgman & Gerard 1990, Alvarez-Buylla 1994, Silva Matos et al 1999. One probable cause for this absence is a lack of knowledge of how the vital rates of different stages are affected by changes in density.…”

Forest spatial heterogeneity and palm richness, abundance and community composition in Terra Firme forest, Central Amazon

“…However, in the Amazon forest the effects of plant community succession (Losos 1995), forest fragmentation and edge effects (Scariot 1999), soil conditions (Peres 1994), leaf litter thickness (Cintra 1997a), tree-fall gap size and distance to the nearest gap (Uhl et al 1988, Cintra & Horna 1997, Svenning 2000, seedling density and distance to the nearest neighbor and adult (Cintra 1997b), vegetation cover and light (Cintra & Terborgh 2000) have been demonstrated to affect palm seedling growth and survival and adult community composition. In the Brazilian Atlantic forest palms density dependence seems to be important only during the seedling stage (Matos et al 1999).…”