Mass allocation, moisture content, and dispersal capacity of wind‐dispersed tropical diaspores

Abstract

Among 34 wind‐dispersed tree species on Barro Colorado Island, Panama, the wet mass of diaspores ranges over six orders of magnitude, The seed mass as a percentage of diaspore mass (S/D) varies greatly among species from 14 to 94% with a mean value of 61% The mean percent moisture of diaspores is 10% no consistent differences occur between seed and non‐seed components of diaspores in percent moisture. Wing‐loading (weight/area) and hence dispersal capacity varies over one order of magnitude among these species and is correlated more highly with S/D than with percent moisture of diaspores. Compared to fruit diaspores, seed diaspores have less mass and a greater S/D, and are slightly more dehydrated. As a result, seed diaspores have lower wing‐loading and greater dispersal capacity than fruit diaspores. The morphological/aerodynamic features of a diaspore also have a significant effect on the mass variables. Overall, the type of diaspore (fruit or seed) is of major importance in explaining mass differences of diaspores among these wind‐dispersed species; morphological features and dehydration ability contribute secondarily. Copyright © 1988, Wiley Blackwell. All rights reserved