Namibia's diversity and wealth of plants
There would be little life without plants. Plants convert solar energy into chemical energy, which they and all animals then use to grow and reproduce. They absorb nutrients from the soil and air, which are then used to make wood, leaves, flowers and fruit. Plants are thus the primary producers of energy and nutrients for life on Earth. They produce oxygen too. Apart from providing us with sustenance, we use plants as a source of medicine and to supply materials to build our houses, cook our food and keep warm, and we exploit the fossilised remains of their predecessors turned, long ago and over eras, into coal, natural gas and other petroleum fuels. Plants help cool the earth and limit the degree of global warming by absorbing carbon dioxide.
The values of plants also change, even over short periods. At the turn of the twenty-first century, it was agreed that dense bush was a problem in Namibia, using terminology such as 'bush encroachment' and 'invader bush' to describe it. Now, dense bush has an economic value developed through charcoal and browse production, and perhaps in earning credit for its role in storing carbon from the atmosphere. Thousands of jobs have been created in Namibia from dense bush. Namibia has also developed 'community forests' to enable communities to manage their plant resources and to commercially harvest a variety of indigenous plant products – devil's claw, marula fruit and oil, commiphora (omumbiri) resin, ximenia oil and !nara fruit, to mention a few.
The pages ahead offer information on some of these important species, as well as on Namibia's vegetation types, cover and biomass production, its plant diversity and richness and some of the factors that affect these, such as fire, climate and invasive plant species.
Photo: Plants in Namibia have a tough life! Evaporation is high, and rainfall is scarce and sporadic. Soils often lack moisture and nutrients. A few lucky plants live next to rivers or above groundwater within reach of their roots. For others, the best strategy is to lie dormant until rains allow them to grow and reproduce. Some lose their leaves, not attempting to retain moisture above ground, while others, such as these quiver trees, preserve water in succulent leaves and stems.
But most individual plants simply die after a short time. Their future lies in their genes wrapped in seeds hidden in the soil. This is the opportunistic strategy of these grasses that soften the landscape around Giant's Playground near Keetmanshoop. They and many other ephemeral plants restrict life to short periods after good rain. Their seeds then germinate into new plants that grow, flower and produce new seeds to wait out the next dry years when living above ground is a challenge.