Collaborative Crop Research Program The McKnight Foundation
CCRP topic:
Soil health management

CCRP projects

»Andes CoP
»East & Horn of Africa CoP
»Southern Africa CoP
»West Africa CoP
»Non-CoP projects

Background information on soils
Soil health management
Soil conservation (erosion control, tillage, moisture conservation)
Integrated nutrient management (INM): Overview
INM: Replenishing soil organic matter
INM: Replenishing mineral nutrients


Food security and human nutrition are inextricably linked to the maintenance of productive, healthy agricultural soils. When soils become degraded, farmers get caught up in a vicious cycle of poverty and food insecurity that compromises their ability to live healthy and productive lives; as crop yields decline, it becomes increasingly difficult to feed their families and earn income.

In many countries where people suffer chronic food security problems, the soils are old and highly weathered; they have inherently low levels of mineral nutrients and are dominated by types of clays that don't retain plant nutrients well. Their nitrogen content, as well as their capacity for nutrient retention, is most strongly related to the soil's organic matter content. But, clearing the soil of its natural vegetation and bringing it into cultivation results in a rapid decline in soil organic matter. Continuous cropping without returning organic matter to the soil, protecting the soil from erosion, and replenishing the nutrients removed with the harvested crop rapidly depletes soil fertility and generally causes the soils to become completely degraded (non-productive) within a relatively short period of time. Previously, people would leave depleted soils fallow for the number of years it would take nature to restore their fertility, but this is no longer a viable option in the face of increasing human population pressures.

It is possible to intensify agricultural production and maintain the productivity of soils indefinitely. (Chinese farmers have maintained the productivity of some soils for centuries, for example.) However, this requires a strategic plan for replenishing soil organic matter, as well as making judicious use of fertilizer inputs to replace the nutrients removed by cropping. Because external inputs are costly and many organic matter management technologies are labor-intensive, maintaining soil productivity is likely to be most challenging in countries in Sub-Saharan Africa, the Andes, and wherever else a large portion of the rural population is already severely impoverished; the poorest people tend to have to spend all of their financial (and energy) resources on day to day survival, and therefore have nothing left over to invest in soil resource management, despite the fact that this is key to their ultimate well-being. Integrated soil management is a knowledge-intensive approach that aims to empower farmers to make the most strategic use of whatever organic and inorganic nutrient resources they have (or can develop) by understanding how to deploy them in the most efficacious and efficient ways possible.

We provide links to additional web-based information, as well as a list of scientific references, for each of the related soil management topics that appear below. We hope that these information resources will help to enhance understanding of some of the complex issues involved in soil management, as well as to be of practical use in farmer outreach programs. We would appreciate your feedback concerning which information is useful and which is not.

Relevant links

Online literature resources
The Essential Electronic Agricultural Library (TEEAL)

  • Website: TEEAL
  • Description: "TEEAL is an annually updated full-text and bibliographic library of over 100 of the world's most important scientific journals in the field of agriculture. TEEAL is available at well below cost to over 100 low-income countries, as listed in the World Bank's 1998-99 World Development Report."

Acess to Global Online Research in Agriculture (AGORA)

  • Website: AGORA
  • Description: "The AGORA program, set up by the Food and Agriculture Organization of the UN (FAO) together with major publishers, enables developing countries to gain access to an outstanding digital library collection in the fields of food, agriculture, environmental science and related social sciences. AGORA provides a collection of 849 journals to institutions in 69 countries. AGORA is designed to enhance the scholarship of the many thousands of students, faculty and researchers in agriculture and life sciences in the developing world."

Health InterNetwork Acess to Research Initiative (HINARI)

  • Website: HINARI
  • Description: "The HINARI program, set up by WHO together with major publishers, enables developing countries to gain access to one of the world's largest collections of biomedical and health literature. Over 3230 journal titles are now available to health institutions in 113 countries, benefiting many thousands of health workers and researchers, and in turn, contributing to improved world health."

World Wide Soil Health Information Portal

  • Website: Cornell University
  • Description: The Worldwide Portal to Information on Soil Health offers an extensive, searchable database of annotated English and Spanish language soil health information resources. The portal gives users access to a subject-specific browsing library, an online resource reference service, and classified resource listings for products, services, organizations, databases, and literature related to soil health.

FAO technical information on soils
The Land and Water Publications

  • Website: The Land and Water Publications Series Directory
  • Description: A treasure trove of technical information on soils! Entire books in PDF version are available for download and printing or are presented in HTML format (no loading time; for reading on line). The directory lists the titles included in the different land and water publication series, several of which are also available in French and/or Spanish. Make sure to keep scrolling down in order to see all of the individual titles.

Corporate Document Repository

  • Website: Corporate Document Repository
  • Description: If PDF versions of specific FAO technical books and reports are too large (making them difficult to open without a fast internet connection), this is a good place to check for HTML versions of those documents.

World Agricultural Information Centre (WAICENT) Portal

  • Website: WAICENT Portal
  • Description: A directory that provides links to approximately 250 main sites and subject entry points for accessing FAO technical information.

The Agricultural Library

  • Website: The Agricultural Library
  • Description: The Agricultural Library has the full text versions (some HTML, some PDF) of many out of print and public domain classics of organic / holistic agriculture. You can find books by (and about) Sir Albert Howard, Lady Eve Balfour, J. Rodale, as well as King's Farmers of Forty Centuries, Dale and Carter's Topsoil and Civilization and many, many others.

© McKnight Foundation Collaborative Crop Research Program.