Biological resources are particularly important in resource-limited countries where
utilisation demands challenge conservation efforts. The study focussed on Berberis
holstii, a plant resource on high demand in northern Malawi restricted to Nyika National
Park. The uses, distribution, habitat characteristics, demography and seed germination
requirements of this important species were investigated. Uses were investigated by
means of ethnobotanical interviews. The species distribution in the park was mapped
employing GIS. Habitats were characterised employing multivariate methods
implemented in the programmes PC-ORD and PRIMER. Demographic studies employed
matrix projections to characterise representative populations. Finally, laboratory
germination trials allowed determination of light, cold stratification and temperature
requirements for seed germination.
Forty-seven uses were documented. Of these, thirty were medicinal and the rest for
income generation. The most common uses included infusion for coughs, malaria,
stomachache, sexually transmitted infections and pneumonia. Because roots are
employed, whole plants are dug out. This lead to the extinction of five of the recorded 94
sites. Fire periodically kills the aerial part of plants, which then tend to recover through
resprouting. The species is restricted to high altitude, open areas on sandy/loamy soils.
Despite harvesting and fire, demographic projections showed positive population growth.
Population growth rate is more sensitive to mortality of late juvenile stages and early
adult stages than it is to demographic transitions and contributions by other stage
classes. Germination was higher when seeds were stored for one year, had a prechilling
treatment (cold stratification) and were germinated under light at -20°C. Seeds
did not lose viability during two years of storage raising prospects for their artificial
storage.
The study provides important information for the conservation and management of this
important African endemic. It highlights some of the difficulties confronted in projecting
the population dynamics of species with sporadic simultaneous recruitment and tests the
ability of a recently proposed model to determine germination requirements. In a wider
context, the study shows that a combination of methodological approaches
(ethnobotany, biogeography, demography and germination) allows a more complete
understanding of the evolutionary, ecological and social factors that must be taken into
account in the conservation of individual species.
Date of Award | 2008 |
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Original language | English |
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Awarding Institution | |
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THE CONSERVATION BIOLOGY OF BERBERIS HOLSTII ENGL. IN NYIKA NATIONAL PARK, MALAWI
NYIRENDA, C. P. M. (Author). 2008
Student thesis: PhD