CHOESIN, DEVI N.1*, SRI AMNAH S.2, and H. TAUFIKURAHMAN1. 1Department of Biology, Institut Teknologi Bandung, Bandung 40132, Indonesia; 2Haluoleo University, Kendari 93232, Indonesia. - Ecological aspects of Vaccinium varingiaefolium growing in a stressed volcanic environment.
Vaccinium varingiaefolium (Ericaceae) is a dominant species
found in many subalpine forests (above 1800-2000 meters) on the
mountains of Java, Indonesia. As a species with high plasticity, it
can grow as a tree of up to 20 meters tall under favorable conditions,
or as a shrub in open, dry, or nutrient-poor substrate. It is also a
pioneer species on ashy or volcanic soil of crater ridges. We compared
several morphological and ecophysiological aspects of V.
varingiaefolium growing at 0, 100, and 200 meters away from the
main crater of Mount Tangkubanparahu volcano in Western Java.
Measurements indicate that ambient concentrations of volcanic sulphur
dioxide decreased as we move away from the crater. Chlorophyll
content, leaf proline content, mean leaf area, plant height and stem
diameter of V. varingiaefolium increased with greater distances
from the crater, while mean leaf thickness decreased. However, there
were no significant differences among locations in terms of plant
transpiration rate, total sulphuric compounds in leaves, number of
stomates, and number of fruits. This last finding suggests that
reproductive allocation by V. varingiaefolium may not be
affected by stress. We are currently conducting further studies to
understand allocation and life history patterns in this species.
Key words: Ericaceae, Indonesia, Tangkubanparahu, Vaccinium varingiaefolium, volcano