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Guiding Acid Soil Management Investments in Africa (GAIA) is a research-for-development project led by the International Maize and Wheat Improvement Center (CIMMYT) and supported by the Bill and Melinda Gates Foundation.

The project aims to identify and address key knowledge gaps related to soil acidity management for sustainable agricultural productivity and maintenance of soil health. GAIA is focused on the development of scalable innovations to provide reliable, timely and actionable data and insights on acidity-related soil health and crop performance, at farm and regional levels. The project has undertaken broad-scale analysis for all of sub-Saharan Africa, with more focused field and policy-engagement activities in Ethiopia, Kenya, Rwanda and Tanzania.

Regional partners include: the Ethiopian Institute of Agricultural Research (EIAR), the Kenya Agricultural and Livestock Research Organization (KALRO), the Rwanda Agriculture and Animal Resources Development Board (RAB), the Tanzania Agricultural Research Institute (TARI), the Southern Agricultural Growth Corridor of Tanzania (SAGCOT).

Find out more at www.cimmyt.org/projects/gaia

Interested to know more about acid soil management in sub-Saharan Africa?

Our dashboard provides state-of-the-art data and information on acid soil management for the major cereal, legume, root and tuber, and commodity crops in sub-Saharan Africa. The following can be found and downloadable open access from our dashboard either as a spatial product or tabular summaries disaggregated for different administrative units:

  1. Distribution and characterization acid soils (soil pH, exchangeable acidity, ECEC).
  2. Lime rates required to increase crop production and expected crop yield responses.
  3. Profitability of liming under different lime price assumptions.
  4. State-of-the-art technical and scientific resources on soil acidity and acid soil management.

These resources can support (a) prioritization of research and development activities, (b) strategic decision making, and (c) public-private investments on soil health initiatives across the region.

Our 'agronomy-to-scale' approach

Soil acidity can negatively impact crop production and fertilizer use efficiency through a series of soil chemical and biological conditions associated with low pH, most notably aluminum toxicity. Our ‘agronomy-to-scale’ approach to understand and tackle this problem encompasses an ex-ante assessment to prioritize crop by geography combinations benefiting most from acid soil management followed by local validation through agronomy and socio-economic research with regional partners and authorities. See an example of our activities in Tanzania on youtube.

Our team and expertise

Our team is composed of agronomists, soil scientists, and economists from international and national research organizations that ensure the development of sound data and knowledge products and local engagements with farmers, private sector, and governments. See our list of partners here. We can support future investments in:

  1. understanding acid soils and their impact on crop production in sub-Saharan Africa’s cropping systems.
  2. prioritizing acid soil management strategies in the context of a broader agenda on soil health.
  3. supporting the development of policies and directives related to soil acidity and lime value chains.