January 14, 2009
First Digital African Soil Map To Be Available Online
For the first time, a comprehensive digital soil map of sub-Saharan Africa is going to be made and released to the public. The 17.5 million dollar plan will give farmers in 42 countries a "soil health diagnosis" and will advise them on what crops will thrive in their area.
Scientists from the International Center for Tropical Agriculture (CIAT) will obtain soil samples from across Africa and evaluate the nutrient levels. Together with satellite information to create a high-resolution guide, these samples will be dispersed to underprivileged farmers by local workers.
The first step of the project is to construct a global digital map which would cover 80% of the world's soils.
The original four-year program is paid for from a grant given by the Bill & Melinda Gates Foundation and the Alliance for a Green Revolution in Africa (Agra).
"From the farmer in the field, right up to the secretary general of the UN, we need precision soil information," said Pedro Sanchez, of Columbia University's Earth Institute, "but we do not have this in sufficient detail. For example, in the whole of Malawi there is only one fertilizer recommendation for maize - but there are many different soil types."
"We have to get into the 21st century. While other disciplines, such as climate science, have created detailed digital maps, we are still catching up," Sanchez added.
African soils are some of the most difficult to work with in the world, and farmers are frequently burdened with low-yielding crops. 50% of terrain in Africa is unsuitable for farming and can only be used for grazing.
Generally African farmers are only able to give back 10% of the nutrients that farmers everywhere else would give back to the soil.
Agra is trying to aid in harnessing more successful yielding practices, by broadening contact with better seed varieties, irrigation and fertilizers.
However, attempts have been hindered by a need for an up-to-date, all-inclusive map about current soil conditions.
AfSIS wants to target areas where soils are poor, and label the kinds of mineral and nutrients required to augment crop yields.
The map construction will begin with ground observations at 60 areas of 100 square kilometers planned for 21 African countries. This will include satellite images and "legacy" statistics located in archives and other repositories. The high resolution maps will exhibit soil capacities and limits like aluminum toxicity, a widespread weakening quality of tropical acid soils.
The information will be universally available at Africasoils.net. The idea is to create an interactive online tool, which will allow extension workers and policymakers to have the best information to decide how best to restore their "sleeping soils".
The plan is to regulary monitor and revise the map, with a continuing soil surveillance service.
"If we are to reduce poverty, feed growing populations and cope with the impact of climate change on agriculture, we require accurate, up-to-date information on the state of Africa's soils," said Nteranya Sanginga, director of CIAT's Tropical Soil Biology and Fertility Institute.
"With accurate soil maps, we find farmers can increase their yields by around 60%, and sometimes double.
"But currently, our best African soil map has a resolution of 10km, squared," she said. "With this new project, we can improve that resolution to a level of one hectare (100 meters, squared)."
Scientists are anticipated to start uploading their information online by the end of 2009, with the complete map available in four years.
After that, AfSIS experts will give training to people "on the ground," like agricultural extension agents, on how to understand and interpret the soil map data for field use.
On the Net:
- International Center for Tropical Agriculture
- World soil maps
- Columbia University's Earth Institute
- Alliance for a Green Revolution in Africa