Posthurricane Seedling Structure in a Multi-aged Tropical Dry Forest: Implications forCommunity Succession

作者：Carrington Mary E^*; Ross Michael S; Basit Alia F

来源：Biotropica, 2015, 47(5): 536-541.

DOI：10.1111/btp.12244

• Caribbean forests
• chronosequence
• disturbance
• Florida

Hurricane-caused tree mortality in tropical dry forests occurs predominantly in early successional species. Consequently, hurricanes may accelerate succession in these forests. Forest regeneration, however, must be measured over an extended posthurricane time period to demonstrate this pattern. In this study, we recorded tree seedlings in 19 Florida Keys forests during May-August 1995, 3years after Hurricane Andrew. For these forestsspanning a chronosequence from 14 to over 100years since the most recent clearingwe used weighted averaging regression on relative abundances of pre-hurricane trees to calculate a successional age optimum for each species; and used weighted averaging calibration to calculate inferred successional ages for stands based on pre-hurricane trees and on posthurricane seedlings. To test the hypothesis that successional stage of seedlings exceeded successional stage of pre-hurricane trees, we compared inferred stand ages based on posthurricane seedlings with those based on pre-hurricane trees. Across the study area, inferred stand ages based on posthurricane seedlings were greater than those based on pre-hurricane trees (P<0.005); however, more seedlings in the youngest stands were early successional than in older stands. Of 29 species present both as pre-hurricane trees and posthurricane seedlings, 23 had animal-dispersed seeds. These results provide evidence that: (1) hurricanes do not reset' succession, and may accelerate succession; and (2) a strong legacy of stand successional age influences seedling assemblages in these forests.

• 出版日期2015-9