A test of the Janzen-Connell model with two common tree species in Amazonian forest

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Field experiments and survival analysis were used to test whether the Janzen-Connell model operated for two common Amazonian tree species in Peru: the midstorey palm,Astrocaryum murumuru, and the canopy-emergent legume,Dipteryx micrantha. Seed and seedling survival patterns of these species partially supported the model, depending on tree species, type of predator, spatial scale and the particular year. At a small scale of a 2.5-ha plot,Astrocaryumseed predation by insects and mammals was density-dependent. At a larger scale of 100 ha,Dipteryxseed survival increased with distance from conspecific adults, but forAstrocaryumseeds there was no distance dependence. At the scale of 200–400 haDipteryxseed survival was negatively related to the number of individuals present in groups of conspecific adult trees. In 1992 a higher proportion ofAstrocaryumseedlings survived far from, compared with close to, conspecific adult trees, whilst in 1993 moreDipteryxseedlings survived beneath conspecific adult trees than farther away.

Related collections

Most cited references 18

Record: found
Abstract: found
Article: not found

Tree dispersion, abundance, and diversity in a tropical dry forest.

S Hubbell (1979)

Patterns of tree abundance and dispersion in a tropical deciduous (dry) forest are summarized. The generalization that tropical trees have spaced adults did not hold. All species were either clumped or randomly dispersed, with rare species more clumped than common species. Breeding system was unrelated to species abundance or dispersion, but clumping was related to mode of seed dispersal. Juvenile densities decreased approximately exponentially away from adults. Rare species gave evidence of poor reproductive performance compared with their performance when common in nearby forests. Patterns of relative species abundance in the dry forest are compared with patterns in other forests, and are explained by a simple stochastic model based on random-walk immigration and extinction set in motion by periodic community disturbance.