Comparing South Africa with Brazil in terms of potential for biofuel production is like comparing peanuts with coconuts and could be dangerous if taken too far, according to well-known soil scientist and consultant Prof Giel Laker of Pretoria.
Laker, who recently reviewed a scientific a paper dealing with changes in land use patterns in the western Bahia district of Brazil, said that soil and rainfall maps from the two countries show there are absolutely no similarities in respect of these resources.
‘’The area is dominated by oxisols on flat plains, with average rainfall ranging between 800mm – on the driest side – and 1 600mm. During the past 20 years about 1,6 million hectares were deforested and put under rain-fed cropping, mainly soya and maize. Scarily, during the same period, about 350 000ha of cultivated land was abandoned in the same area, baring it to different forms of soil degradation, especially erosion.
The fact that this land is more than 20% of the size of the new areas brought under cultivation seems to indicate that the farming system is not sustainable. ‘’In comparison, South Africa has very limited arable land. The annual rainfall in the areas where we grow soya and maize is only between 450mm and 700mm. That’s why growing crops for biofuel production could have serious implications for national food security and food affordability for the poorest sections of the population,’’ Laker said. – Roelof Bezuidenhout