Many farmers across sub-Saharan Africa try to coax crops out of sandy soils that are not ideal for holding water and nutrients. Their harvests are predictably poor. A traditional approach would have them apply more fertilizers and use irrigation, but both of these options require access to resources and infrastructure that many of them do not have. A relatively new technology modeled for eight African countries, and currently being tested in Zimbabwe, shows potential for substantially improving harvests through increased water retention and accumulation of organic material to make soils more fertile.

The technology consists of long strips of polyethylene membranes installed in a U-shape below and near the root zones of crops. Known as subsurface water retention technology (SWRT), these membranes have mostly been used in different soils in other regions of the world. Now for the first time, their impact was modeled for Africa. Projected results showed that the SWRT could increase maize yields in the eight African countries in the study by close to 50 percent and capture some 15 million tons of carbon in 20 years.

"With this new technology, sandy soil has the potential to lead a new green revolution," said George Nyamadzawo, a professor at Bindura University in Zimbabwe.

The researchers said this simple technology, if deployed and adopted at scale, could address major issues facing sub-Saharan African farmers, including food security and erratic rainfall patterns, while also helping countries meet climate change mitigation targets. The study was published in Frontiers in Sustainable Food Systems in in September.

(Source: Agriculture and Food News, ScienceDaily. www.sciencedaily.com)