Soil seed bank characteristics in relation to different shrub species in semiarid regions

Abstract

Little information is available about the effects of different species of shrubs on the composition of the soil seed bank (SSB) and how the SSB could contribute to the restoration of degraded area in semiarid regions. We determined the role of three dominant shrub species on SSB characteristics and evaluated their potential for their possible use in rangeland restoration projects. Fifteen sites, each containing three shrub species (Amygdalus scoparia, Daphne mezereum and Ebenus stellata) and a herbaceous patch (control) in close proximity, were sampled and their SSB density, species richness and diversity at 0-10 cm depth were determined. The results showed that density of the SSB was highest under A. scoparia (1133 seeds per m2) and lowest in herbaceous vegetation (110 seeds per m2). Species richness and diversity of the SSB was significantly greater under E. stellata than under the other shrubs and control. This study revealed that the extent to which vegetation affected SSB characteristics did not only depend on the presence of shrubs, but also on the species of shrub. These different roles of different species of shrubs on SSB are advised to be considered in restoration of degraded areas through conservation of shrubs in semiarid regions.

Study of the Soil Seed Bank Composition in Arjo-Diga Humid Afromontane Forest under Different Land Use Types and Its Implications for the Restoration of Degraded Lands in Western Ethiopia

“…Te dominance of herbaceous species and species of the Asteraceae and Poaceae plant families in the soil seed bank could be due to species seeds being small, light, and winged [48]. Tis characteristic makes seeds more durable and dispersible through a variety of mechanisms, contributing to their high species composition in the soil seed bank [42,49,50]. Another possible reason is that herbaceous species have a better chance of recovering from disturbance because they produce many seeds quickly and spread over long distances [4,43].…”