학술논문

Irregular droughts trigger mass flowering in aseasonal tropical forests in Asia
Document Type
Report
Author abstract
Source
The American Journal of Botany. August, 2006, Vol. 93 Issue 8, p1134, 6 p.
Subject
Droughts -- Influence
Rain forests -- Evaluation
Plants, Flowering of -- Environmental aspects
Biological sciences
Language
English
ISSN
0002-9122
Abstract
General flowering is a community-wide masting phenomenon, which is thus far documented only in aseasonal tropical forests in Asia. Although the canopy and emergent layers of forests in this region tire dominated by species of a single rurally, Dipterocarpaceae, general flowering involves various plant groups. Studying proximate factors and estimating the flowering patterns of the past and future may aid our understanding of the ecological significance and evolutionary factors behind this phenomenon. Here we show that this phenomenon is most likely triggered by irregular droughts based on 10 years of observations. In the aseasonal forests of SE Asia, droughts tend to occur during transition periods from La Nina to El Nino, which results in an irregular 6-7-yr cycle involving a dry period with several droughts and a wet period without droughts. The magnitude of a flowering event also depends on the timing of droughts associated with the El Nino southern oscillation (ENSO) cycle, with the largest events occurring after an interval of several years with no flowering. Because most plant species can only reproduce successfully during large flowering events, changes in the ENSO cycle resulting from global warming, may have serious ramifications for forest regeneration hi this region. Key words: Borneo; dipterocarp forests: Lambir; mass flowering; masting; Malaysia: phenology; Sarawak.