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Phenological niches of coexisting serotinous plants in the Namib Desert

Published online by Cambridge University Press:  10 July 2009

Antje Günster
Antje Günster
Affiliation:
Desert Ecological Research Unit of Namibia, PO Box 1592, Swakopmund, Namibia
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Abstract

Timing of germination and flowering under different environmental conditions was investigated in four coexisting serotinous desert plants: Blepharis grossa (annual herb), Geigeria data, Geigeria ornativa (facultative perennial herbs) and Petalidium setosum (perennial shrub). Germination patterns were similar under varying environmental conditions in the study species, except for P. setosum, which germinated later when conditions were less favourable. B. grossa always germinated early, G. alata and G. ornativa later, which could be explained by differences in their seed dispersal mode. Thus no obvious niche separation in timing of germination was indicated in the study species. Flowering periods varied between seasons rather than between species and no niche separation in flowering times existed between the study plants. This might indicate that either interspecific competition plays a minor role in a community of desert serotinous plants or that niche separation exists in other components of the plants' niche, such as seed dispersal, seedling establishment and/or microhabitat selection.

Keywords

seed dispersaldesertgerminationNamibianiche separationphenologyserotiny
Type
Research Article
Information
Journal of Tropical Ecology , Volume 10 , Issue 4 , November 1994 , pp. 531 - 544
Copyright
Copyright © Cambridge University Press 1994

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References

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