What drives the vital rates of secondary hemiepiphytes? A first assessment for three species of Heteropsis (Araceae) in the Colombian Amazon. (17th April 2015)

• Record Type: Journal Article
• Authors: Balcázar-Vargas, María Paula; van Andel, Tinde R.; Westers, Paul; Zuidema, Pieter A.
• Is Part Of: Journal of tropical ecology. Volume 31:Part 3(2015:May)
• Page Start: 251
• Page End: 265
• Publication Date: 2015-04-17
• Subjects: Ecology -- Tropics -- Periodicals; 577.0913
• DOI: 10.1017/S0266467415000115
• Languages: English
• ISSNs: 0266-4674

Abstract

<abstract abstract-type="normal"> <title>Abstract:</title> <p>Secondary hemiepiphytes rely on other plants (hosts) to grow vertically. After germinating on the forest floor, their seedlings search a host to ascend. We recorded information on survival, growth, reproduction and vegetative propagation of three <italic>Heteropsis</italic> species, to evaluate what drives their vital rates. We measured 700 individuals of each study species between 2007 and 2009 in the southern Colombian Amazon. A gradual increase in stem length, leaf size, number of roots and plagiotropic branches was found with increasing height of <italic>Heteropsis</italic> individuals on their hosts. Survival of leafless non-climbing seedlings was very low (28% annually); increasing substantially (84–94%) once the seedling had ascended a host. The three <italic>Heteropsis</italic> species presented slow height growth rates (<italic>c</italic>. 2–8 cm y⁻¹) with large variation, while a substantial percentage of the stems (31–62%) did not grow or dried out. Vegetative propagation in <italic>Heteropsis</italic> may act as a dispersion-propagation strategy to find a suitable host and reach the canopy again after falling. The slow growth rates suggest that <italic>Heteropsis</italic> individuals that have reached the canopy are rather old. Once plants have reached the tree crowns, their longevity is largely determined by the survival of the host tree.</p> </abstract>