Eucalyptus Helps Reverse Erosion in Mali
by Eliza Barclay, Nomad on 12.11.07
BBC News has a story out of Mali in West Africa that describes how a women's co-operative in the village of Kabara, south of Timbuktu, is using underground aquifers to plant eucalyptus trees. In this region where the annual rainfall is less than 400mm, reforestation is essential to return nutrients to the soil, and to prevent erosion by the harsh desert winds.
Though some scientists are worried that the eucalyptus trees will drain large amounts of water out of the soil, Daouda Diarra from the World Food Program in Mali says they are a good choice in the desert environment.
"Eucalyptus is especially recommended for its rapid growth and the protection it gives against strong winds," Mr Diarra told the BBC. "In dry zones, a five-year-old tree's root system actually pumps water back into the water table."
Farmers in the region are also developing other methods, like building dirt mounds around a field, to harvest and conserve rainwater and improve food security.
When WFP Executive Director Josette Sheeran visited northern Mali last month, she said she was confident that thanks to fairly decent rains and some of these innovations, the food security outlook for this year was decent.
"We now have science and technology to help us create sustainable food systems in all climates," Ms Sheeran told the BBC. :: Via BBC News
aren't they also highly invasive and allelopatric? Aren't there any native plants they can use?
It is interesting to see the effect on other places where it has been introduced, creatinga an arid landscape and posing a new fire hazard.
But eucalyptus pulp is very commercial, so I can imagine there are other motivations to this plantation effort.
Mali has never been a highly forested place. Look what happened when they irrigated southern California. Once you get a drought, the very soil catches on fire.
Some places are MEANT to be arid.
Scientists have genetically engineered a tobacco plant that shuts off a gene which causes the plant to lose it's leaves when experiencing shock after not being watered for a couple weeks. As a result the plant can survive longer periods of drought or neglect. Since the gene is present in all plants this has the capability of providing a variety of plants that can stem soil erosion and desertification like the Sudanese grass that was planted in America during the Dust Bowl.
Some of the changes they are making are very valid and definitely should be applauded.
That said, I think the choice of Eucalyptus for reforestation is not a good idea. I've never been to Africa, but I spent a lot of time in Latin America working in permaculture and sustainable agriculture.
A nitrogen fixing leguminous tree native to that particular area would be a much better solution. (I believe that's something like the Sahelian Acacia). It's slower growing, and maybe harder to keep alive, but reforestation is still measured in years and decades.
Latin America was also given the Eucalyptus with great promises of instant forests. What they got are eerie groves of trees where nothing else grows, the leaf litter kills anything native.
I would really like to see the specific scientific study that explains Mr. Diarra's point to the BBC. "In dry zones, a five-year-old tree's root system actually pumps water back into the water table."
i think the fact that its highly invasive is the point of planting it. But i still don't understand why there using a non native plant. Aren't there native plants for this?