To better understand the physiognomy and dynamics of tropical forest canopy trees, the mortality, recruitment, and growth rates of trees greater-than-or-equal-to 30 cm DBH were quantified on a montane tropical rain forest hillslope over the 10-yr period 1982-1992. The results indicate that the smaller stature of canopy trees growing on or near ridge-crests of montane rain forests is a consequence of higher turnover rates, not slower growth rates. The annual canopy tree turnover rate of approximately 1.7 percent in the upslope section of the sample area was two times greater than in the downslope section. The DBH growth increments in the upslope and downslope sections also were significantly different (P < 0.05), but it was the upslope trees that grew at the faster rate (upslope = 3.1 mm yr-1; downslope = 2.4 mm yr-1). The mean DBH growth increment of 2.7 mm yr-1 for the entire plot is relatively high compared to other montane tropical rain forests. Interspecific variation among the 23 tree species also was notable, with mean DBH increments ranging from 0.4 to 7.8 mm yr-1. Ceratopetalum virchowii and Elaeocarpus ferruginiflorus were the most dominant species in 1982: C. virchowii increased its dominance over the 10-year period with a higher rate of recruitment than mortality and a change in relative importance from 22.7 percent in 1982 to 28.4 percent in 1992; E. ferruginiflorus, in contrast, experienced the most significant change of all the species examined, with a decrease in relative importance from 14.1 percent in 1982 to 5.3 percent in 1992 as a result of its high mortality, its slow growth rates, and its failure to recruit any individuals into the greater-than-or-equal-to 30 cm DBH size-class; the local demise of this species may be part of a shifting floristic mosaic associated with natural disturbance events or perhaps part of an irreversible trend. It is recommended that more attention be directed to the growth patterns of co-occurring species and the life histories of individual trees to obtain a clearer sense for the long-term dynamics of montane tropical rain forest canopy tree populations.
