Newsletter of the Southern African Botanical Diversity - SANBI

Plant taxonomy in the 21 st Century:
meeting users’ needs in Lesotho
This article is an outcome of a lecture presented at a national workshop for end-users
and stakeholders of botanical information and herbaria, held in Mohale, Lesotho in
October 2003. The article discusses plant taxonomy in the 21 st Century in light of how
end-users of botanical information could use taxonomic data in conserving species and
habitats. It also describes taxonomy as an integral part of biodiversity and sustainable
development and presents a summary of the kinds of information that taxonomy
and herbaria can provide for stakeholders and end-users in the social, economic and
environment sectors. Throughout, the discussion attempts to relate taxonomy and
herbaria to the themes of biodiversity, sustainable development, and human needs.
Human Beings: the earth’s most
biologically successful species
In trying to provide food, shelter, sanitation,
and health care for 6 billion people,
the Earth’s natural resources are being
depleted. In turn, the functioning of ecosystems
is being disrupted. An important
component of ecosystems is biodiversity.
Among the most important threats to
biological diversity in the 21 st Century
are land degradation, globalisation, and
climate change, which are all driven by
the impact of humans.
Degradation of habitat
Land degradation is a major problem.
About 75 percent of the Earth’s landmass
has been degraded to some degree by
human impact. In Africa, land is being
transformed by agriculture, deforestation,
grazing, mining, and the collection
of firewood. These economy-driven activities
continue to destroy natural habitats
and progressively wipe out species and
populations. The destruction of habitat
threatens many plant species that may be
useful for the alleviation of hunger or disease.
Normally, gene flow between plant
populations introduces new genes and
therefore variation into the gene pool of
the populations. Increased variation allows
populations to adapt to changing environmental
conditions and save themselves
from possible extinction. However, the
degradation of habitat causes the isolation
of populations and reduced gene flow and
variation in populations, thus restricting
their potential for adaptation.
Globalisation
Globalisation has both positive and
negative effects on nations. The most
significant negative effect of globalisation
in developing countries is cultural loss.
The homogenisation of cultural diversity
through globalisation results in the cultural
knowledge and practices of indigenous
people becoming threatened. In
addition, global influences undermine the
family and religious values of indigenous
communities. This alters their social values
and sustainable practices. Such cultural
changes increase challenges to conserve
biological resources (Hoyningen-Huene,
et. al. 1999).
Climate change
Climate change affects the conservation
of biological diversity. Desanker (2002)
explains that climate change may intensify
the stress on ecosystems to beyond
recovery, which would have significant
effects on biodiversity and food security,
especially in Africa. He suggests that biodiversity
be managed to ensure that the
conservation of species takes place both
within and outside conservation areas, and
that adequate habitat be preserved to enable
species of plants and animals as well
as humans to migrate when necessary.
Human activities such as deforestation are
speeding up the process of climate change
in the 21 st Century, which will disrupt food
production and intensify poverty. When
biological diversity is conserved, ecosystems
are conserved and therefore able to
continue to support human life.
The good news for southern African
countries is that much of their rich biological
diversity is still intact in the form
of ecosystems. The exceptional richness
of the southern African flora alone is
highlighted in The relevance of herbaria
and taxonomic work in southern Africa in
Steenkamp & Smith (2002). The survival
of the subcontinent therefore depends
on the wise utilisation of these genetic
resources.
Prescription for the 21 st century
All human life is dependent on the sustainable
use of biological resources. Meeting
the demands for housing, education,
SABONET News Vol. 9 No. 1 September 2004
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