Within-gap spatial heterogeneity and seedling performance in a Mexican tropical forest
Por:
Nunez-Farfan J., Dirzo R.
Publicada:
1 ene 1988
Resumen:
The internal heterogeneity of gaps was investigated by comparing 1) the floristic composition and structural organization of colonizing seedlings and 2) the performance of Cecropia obtusifolia and Heliocarpus appendiculatus, in the root and crown zones of fallen trees in the tropical rain forest of Los Tuxtlas. Considerable differences were found between the zones regarding number of species and diversity; likewise, the floristic similarity of quadrats of the zones was always lower than that of the quadrats of the same zone. The exclusive species of each zone, or even the shared species were present with different density or size (or both), leading to different hierachical organizations. Cecropia obtusifolia survived better in the crown than in the root zone; H. appendiculatus showed the opposite response. Herbivory by insects accounted for a large proportion of the mortality of the plants: mortality rates were higher for seedlings that had previously been heavily damaged. Physical damage, especially from falling objects was also an important source of mortality. These causes of mortality varied between zones. -from Authors
Filiaciones:
Nunez-Farfan J.:
Dept de Ecol, Inst de Biol, UNAM, Ap Post 70-233, 04510 DF, Mexico, Mexico
Dirzo R.:
Dept de Ecol, Inst de Biol, UNAM, Ap Post 70-233, 04510 DF, Mexico, Mexico
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