Abstract
In June 1990 a research project sponsored by DANIDA and AWF was carried out by botany students of Nairobi University to investigate the regeneration strategy of mangroves at Gazi bay and Mida creek. Statistical analysis of 449 quadrats (5 × 5 m) sampled along 35 line transects in 4 mangrove forests showed that mangrove seedlings follow the same distribution pattern in the intertidal zone as their parent trees. In other words, mangrove seedlings mainly develop within a well-defined species specific zone. These distribution zones for the various mangrove trees and their seedlings are defined in terms of elevation above the mean low water level of spring tides.
Through assigning mangrove seedlings in the intertidal zone to the categories (i) ‘fixed’ or ‘not-fixed’, and (ii) ‘covered’ or ‘not-covered’, evidence was found that propagule dispersal followed both the ‘self-planting’ theory and the ‘stranding’ theory. The ‘self-planting’ theory appeared to be the major mechanism of propagule dispersal in ‘undisturbed’ mangrove forests, whilst the ‘stranding theory’ proved to be predominant in colonizing ‘over-exploited’ and cleared mangrove forests.
It is concluded that re-afforestation of mangrove seedlings in the intertidal zone will be most successful when the seedlings are planted in their specific distribution zones under fixed conditions.
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Van Speybroeck, D. Regeneration strategy of mangroves along the Kenya coast: a first approach. Hydrobiologia 247, 243–251 (1992). https://doi.org/10.1007/BF00008225
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DOI: https://doi.org/10.1007/BF00008225