PARENT SESSION
Oral Session #3: Plant Population Ecology. Presiding: N. Fetcher.
Monday, August 6, 2001. 8:00 AM to 11:30 AM. Hall of Ideas L&M.
Life history diversity of lianas in an eastern Amazonian forest.
Gerwing, Jeffrey1,2, 1 2
ABSTRACT- Lianas are conspicuous elements of many tropical forests yet our understanding of their ecology is poorly developed. Many ecological studies have treated lianas as a homogenous class while others have made comparisons among different climbing modes but not addressed other aspects of liana life history. In this study I sought to address this apparent gap in understanding by comparing the establishment, growth, and mortality of five species of lianas among different light and successional microsites in an Amazonian forest. Over a three-year period I monitored the fates of ca. 2500 rooted liana stems in a 5 ha plot. Three patterns of microsite occupation throughout ontogeny were apparent. For example, one species was strongly associated with high light and early successional microsites in all life stages. In contrast, two species were common in moderate light, mid-successional microsites in all stages except for the transition from free-standing to climbing stems which occurred in canopy gaps. Coupled with these differences in microsite associations were tenfold differences among species in mortality and stem diameter growth rates and there was a pattern of higher growth and mortality rates in species that were more strongly associated with early successional forest patches. The results from this study suggest that tropical lianas are likely to exhibit a range of inter-specific diversity in life history traits that rivals that which has been documented for tropical trees.
KEY WORDS: tropical forest, Brazil, Liana, life history