Timing of seed dispersal generates a bimodal seed bank depth distribution

American Journal of Botany
By: , and 

Links

Abstract

The density of soil seed banks is normally highest at the soil surface and declines monotonically with depth. Sometimes, for a variety of reasons, peak density occurs below the surface but, except in severely disturbed soils, it is generally true that deeper seeds are older. In seasonally dry habitats that develop deep soil cracks during the dry season, it is possible that some seeds fall down cracks and rapidly become deeply buried. We investigated this possibility for three dominant clonal perennials (Scirpus maritimusS. litoralis, and Juncus subulatus) in the Doñana salt marsh, a nontidal marsh with a Mediterranean climate located in southwest Spain. Two species, which shed most of their seed during the dry season and have seeds with low buoyancy, had bimodal viable seed depth distributions, with peak densities at the surface and at 16–20 cm. A third species, which shed most seeds after soil cracks had closed and had seeds with high buoyancy, had viable seeds only in surface soil. Bimodal seed bank depth distributions may be relatively common in seasonally dry habitats with fine-textured soils, but their ecological significance has not been investigated.

Publication type Article
Publication Subtype Journal Article
Title Timing of seed dispersal generates a bimodal seed bank depth distribution
Series title American Journal of Botany
DOI 10.3732/ajb.92.10.1759
Volume 92
Issue 10
Year Published 2005
Language English
Publisher Wiley
Contributing office(s) National Wetlands Research Center
Description 5 p.
First page 1759
Last page 1763
Google Analytic Metrics Metrics page
Additional publication details