WINDHOEK – The bush infestation in Namibia affects 30 million hectares of farmland and has led to a 60 percent decline in commercial livestock farming over the past 40 years.
This is according to a well-known Namibian farmer Nico de Klerk, who was speaking on the sidelines of the 11th Session of the Conference of Parties (COP11) to the United Nations Convention to Combat Desertification (UNCCD), organized by the Desert Research Foundation of Namibia (DRFN). De Klerk said controlling bush encroachment is expensive and the majority of farmers cannot afford bush clearing. Yet bush encroachment is the most devastating factor for sustainable livestock farming and the general standard of living in rural areas. “Presently more then 30 million hectares are affected in the high production parts of the Otjozondjupa Region, as well as in the regions of Oshana, Omusati, Ohangwena, and Oshikoto where the density varies between 2 400 bushes and more than 10 000 bushes per hectare. In the southern part of the country the density is between 1 500 bushes and 2000 bushes per hectare.
Even though the south has different species of bushes, the bushes still have a severe impact on plant growth in those areas. Bush encroachment also has an effect on water as “hydrologists found that with bush encroachment, there is less water inflow into dams and less water to recharge underground reservoirs.” Water losses through transpiration runs into about 12 million cubic metres of water that evaporates on a 5 000 hectare farm. The implication is that during 400 millimetre rainfall on an affected 12 000 hectare farm, water loss can reach an enormous figure of up to 20 million millimetres of water.
“Very little water is left for grass production and underground water recharge. With the density increase over time, boreholes in 1920 only went up to a depth of 18 metres, while in 1996, drilling reached a depth of 85 metres before striking water. Engineers have to drill new boreholes from time to time to find new water resources,” said de Klerk. About 80 percent of Namibia depends on under-ground water for economic activities. “Industries and municipalities depend on ground water and they are also severely affected. Several municipalities around the country face imminent water shortages and will run dry by 2015/2016,” De Klerk said. “If industries in Windhoek and Okahandja alone run out of water, they will record losses of up to N$21 million a day. Water requirements are going to increase from the present 350 million cubic metres to 812 million cubic metres in 2030. With Vision 2030 Namibian engineers have to make sure the country meets the requirements,” he said
By Fifi Rhodes