CoPIs: Cheryl Palm (Columbia University) and Bernard Vanlauwe [International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria]
Key Collaborators: Pedro Sanchez, Markus Walsh, and Ray Weil (Columbia University), and Keith Shepherd [World Agroforestry Centre (ICRAF), Nairobi, Kenya)
The success of the African Green Revolution depends on increased use of fertilizers and improved germplasm, which double or triple yields in many areas compared to current farmer practices. Yet there is growing evidence that yields in many fields remain low, showing little response to fertilizers. There is limited understanding of where, why, and how this soil and crop non-responsiveness occurs. Nutrient inputs that drive the African Green Revolution on the nutrient depleted soils of the continent must be efficiently targeted and managed to realize the benefits of improved crop germplasm. The project has four objectives: (1) quantify the occurrence of crop non-responsiveness to mineral fertilizers as related to soil type, topography/landscape, and management practices, (2) characterize the soil processes and properties that result in crop non-responsiveness to mineral fertilizers, (3) evaluate rapid and cost effective field tools for diagnosing these soil factors, and (4) construct a decision tree for targeting improved management options for non-responsive soils. State-of-the art analytical methods will provide the quantitative characterization of chemical, physical, and biological soil factors underlying non-responsiveness. Expected outcomes include: 1) information on the extent and location of non-responsive soils, 2) description and quantification of the soil factors that contribute to non-responsiveness, 3) efficient and cost-effective field tools to characterize and diagnose soils in terms of non-responsiveness, and 4) decision tools for soil management options to manage and rehabilitate non-responsive soils.
The project will make a substantial contribution to science and methodologies guiding sustainable agricultural production in Africa. A field test kit coupled with a decision tree for diagnosing and managing non-responsive crops/soils will be developed for researchers, policy makers, extension services, and farmers aimed at targeting nutrient management recommendations. Interactions with national scientists and institutions in Africa will develop capacity, knowledge, and methods required to increase and scale up the impact of the African Green Revolution on the productivity of smallholder farms. The project will also mentor, train, and support graduate students and post-doctoral fellows in the United States and Africa through the PI, co-PIs, and collaborating scientists in the project who have all been involved in and led much of the basic and applied soils research and graduate student training in Africa over the past 15 to 20 years. Data will be deposited and publically accessible at the Africa Soil Information Service (AfSIS) website (www.africasoils.net/).
