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Organic Fertilizers in Sub-Saharan Farming Systems

  • Jonas N. ChianuEmail author
  • Justina N. Chianu
  • Franklin Mairura
Chapter
Part of the Sustainable Agriculture Reviews book series (SARV, volume 9)

Abstract

Soil has played major roles throughout human history and civilizations. In sub-Saharan Africa, the soil has been subjected to key challenges such as organic matter export, loss to termites, burning, and diversion to competing uses. These issues lead to a decline in fertility that threatens the sustainability of actual agricultural systems. Therefore the use of organic fertilizers and conservation agriculture is promoted. Farmers recycle organic resources by composting and other practices. However, the adoptions of both organic fertilizers and conservation agriculture have remained low due to limited knowledge on these practices, lack of policy support, and insufficient labor. In response, emphasis on the use of organic resources and mineral fertilizers in Africa has been shifting over the years. Here we review the current role of organic resources in the farming systems of sub-Saharan Africa in order to clarify avenues for enhancing it. The major points are (1) due to their increasing recognition of the role of organic fertilizers in the farming systems, policy-makers in Africa are increasingly supporting issues of sustainable agricultural production systems. (2) There is an increasing awareness on the need for efficiency in the use of organic resources. (3) The consensus that the most sustainable gains in crop productivity are achieved from combined application of organic and mineral fertilizers is driving forward integrated soil fertility management in Africa. (4) Small farmers who are generally unable to apply the recommended rates of organic resources are increasingly experimenting options to upgrade their use of organic inputs.

Keywords

Organic fertilizer Soil quality Soil health Farming systems Sub-Saharan Africa 

Acronyms and Abbreviations

AfDB

African Development Bank

FAO

Food and Agriculture Organization of the United Nations

KARI

Kenya Agricultural Research Institute

N

Nitrogen

ORD

Organic Resource Database

P

Phosphorus

UNEP

United Nations Environmental Program

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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Jonas N. Chianu
    • 1
    Email author
  • Justina N. Chianu
    • 2
  • Franklin Mairura
    • 3
  1. 1.Agriculture & Agro-Industry (OSAN) DepartmentAfrican Development BankTunis BelvedereTunisia
  2. 2.Consultant CIAT-TSBF, c/o World Agroforestry Centre (ICRAF)NairobiKenya
  3. 3.TSBF-CIAT c/o World Agroforestry Centre (ICRAF)NairobiKenya

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