Ensemble model machine learning approach digital soil fertility map of soil-test results coupled with different satellite imageries has changed fertilizer advisory service in Ethiopia
The Ethiopian Soil Information System (EthioSIS) project has covered 748 woredas and 62 confluence points, and gathered hundreds of thousands of soil samples from the entire country to develop 22 different soil property maps and fertilizer recommendations for each region. In addition, the later field survey approach will help to generate bio-physical map of the country. This comprehensive soil assessment is required to achieve an ambitious goal to map the country’s soil and compile in-depth soil fertility information, which could be eventually be used to well inform the fertilizer policies and recommendation and promote significantly higher crop yields. In providing high resolution and detailed soil fertility data, the project has challenged the long-standing belief in Ethiopia that DAP and Urea fertilizers should exclusive and uniformly be used across the country regardless of crop need, soil types and agro-ecology. Instead, it has demonstrated that tailored fertilizer type application can replenish the fertility of a variety of soils found to be deficient in several essential nutrients
Accurate and up-to-date information about soil fertility is critical to developing smart policies regarding the preservation and rehabilitation of Ethiopia’s natural resources. It is particularly important given the country’s present challenge of food security, and its need to formulate effective climate change mitigation and adaptation strategies. Information on the fertility properties of the country’s diverse soils will enable Ethiopia to continue its tremendous gains in crop production and productivity over the coming years, while simultaneously ensuring that growth is achieved through sustainable means and minimizing the overarching challenge of climate change through balanced nutrition.
Since its launch in 2012, EthioSIS has completed soil sampling and laboratory analyses for all the soil samples collected from the entire country. Soil fertility status and fertilizer recommendation atlases have been published for Amhara, Harari, SNNP, Tigray regions and Dire Dawa administration; and handed iver to the regions. Maps of 300 woredas of Oromia regional state are also completed and the printing is ongoing. Preliminary fertilizer recommendation and soil fertility status maps of Benishangul-Gumuz and Gambella regions are also completed. Field surveys for the 748 woredas were completed by June 2017. The Afar and Somali regional states maps are under production, in addition the national soil fertility statues and fertilizer recommendation maps to be ready by August 2019.
EthioSIS is the first initiative of its kind in Africa, employing remote sensing satellite technology and other state-of-the art techniques for soil surveying. Wet-chemistry analysis using instruments with high-detection limits, like MP-AES, ICP and CN analyzers are utilized, as are rapid, non-destructive infrared spectroscopy and laser diffraction particle size distribution analysis techniques. A grid-based survey to map the biophysical resources of the country for long-term decision support. In addition, the project will deliver a national soil map predicted by using ensemble models of different machine learning and geo-statistical methods that increase the accuracy of the model to predict soil properties.
Parallel to the soil fertility mapping, EthioSIS carries out capacity building for the National Soil Testing Center (NTSC) and five regional soil testing laboratories. Each center is furnished with the appropriate equipment for the work it is expected to do, and staff are trained on equipment handling and soil analysis techniques. Construction of Soil archive, advanced level trainings on digital soil mapping and spectral diagnosis and predictions are also the capacity building components.
The project’s extensive soil sampling and laboratory analysis work has led to the recommendation on ways to improve soil health and fertility, including the use of at least 12 different fertilizers, which can be applied with or without potash depending on the status of each soil, to address the nutrient deficiencies of soils around the country.
The fertilizer blending project is one of the complementary activity of the EthioSIS, whose soil fertility maps and fertilizer recommendations have led to the production of tailored fertilizers to address the nutrient deficiencies in Ethiopian agricultural soils. With support from the Government of Ethiopia, five farmers’ cooperative unions (FCU) were selected to produce blended fertilizers in the four largest states in the country: at Becho-Woliso and Gibe-Dedesa FCUs in Oromia, Merkeb FCU in Amhara, Enderta FCU in Tigray, and Melke-Silte FCU in SNNP.
These FCU-owned fertilizer blending facilities are leveraging the data generated by EthioSIS to identify and produce customized blended fertilizers within Ethiopia. Each blending factory has an annual blending capacity of 50,000 metric tons of fertilizers. A nation-wide implementation of massive demonstration trials of new fertilizers on ~ tens of thousands plots at model farmers and Farmers’ training centers (FTC) their productivity gain has convinced smallholder farmers to immediately accept and switch to the new fertilizer package without any reservation