Presentation by Mike McGahuey (Sustainable Agriculture and Natural Resources Management Advisor, USAID) and Jerry Glover (Senior Sustainable Agricultural Systems Advisor, USAID) at the May 15, 2013 event "Natural Resource Management and Food Security for a Growing Population". For more information visit: http://www.wri.org/event/2013/05/natural-resource-management-and-food-security-growing-population

1. Increasing and Sustaining Dryland
Agricultural Productivity In Africa
Challenges, Experiences, Principles
World Resources Institute Roundtable
May 15, 2013
Mike McGahuey and Jerry Glover, USAID

2. Agricultrual Productivity:
Drivers of Progress
• Where have yields increased and
to what degree?
• Where has resilience been
strengthened?
• What problems did they
overcome?
• What practices and principles
did they use?

3. Key Challenges: Low Rainfall-use
Efficiency
• “(Experts) estimate that only 10–15% of the rainfall is
used by the vegetation.”*
• Rainfall Characteristics
– Intensive rainfall events « 25-50% runoff rates**
– Long intervals between events « Frequent need to
replant « Shortened Season
– Periodic droughts « Crop failure for annual staples
*Doumbia, M. (2008) Sequestration of organic carbon in West African soils by Aménagement en Courbes de Niveau Agron.
Sustain. Dev., 2008
**Stroosnijderi, L., & Hoogmoed, W. (1984). Crust formation on sandy soils in the Sahel, Il Tillage and its effect on the water
balance. Soil & Tillage Research, 4, 321-337.

4. Key Challenges: Weathered Soils
and Loss of Coping Strategies
1. “Africa is the world's most ancient land mass.”*
– “Only 10 percent of the soils are relatively young and still have
nutrient-rich sediments.”
– “The soil organic matter content is low.”*
1. Soil are Characterized as
– Nutrient poor « Requires external inputs
– Low inherent capacity to retain nutrients applied in fertilizers (low
fertilizer-use efficiency) « Fertilizers often not economical unless
soil organic matter content is amended
1. Demographic Pressure has reduced options for soil
regeneration and coping with drought and pushed
people to the margin
Breman, Henk, et.al. (2005). THE LESSON OF DRENTE'S 'ESSEN‘: SOIL NUTRIENT DEPLETION IN SUB-SAHARAN
AFRICA AND MANAGEMENT STRATEGIES FOR SOIL REPLENISHMENT. International Center for Soil Fertility
and Agricultural Development

5. Soil Organic Matter (SOM) and
Fertilizer-Use Efficiency
• “in the Sudano-Sahelian zone, the effective cation exchange
capacity (ECEC) is more correlated to organic matter than
to clay,”*
• Recovery of N-fertilizer as related to SOM:*
– Infields (high SOM): 34% - 37%
– Outfields (low SOM): 17% - 23%
• ”in the surface horizons of tropical African soils, soil organic
matter contains practically all of nitrogen and about 20±80% of
phosphorus.”
Bationo, A., F. Lompo, S. Koala (1998) Research on nutrient Flows and balances in West Africa: state-of-the-art; Agriculture,
Ecosystems and Environment 71 (1998) 19±35
*Bationo, A, et.al., 2006. African Soils: Their Productivity and Profitability of Fertilizer Use. Background paper prepared for the
African Fertilizer Summit. The International Fertilizer Development Center.

6. Returns to Fertilizer as a
Function of SOM
Estimated marginal value product of nitrogen fertilizer
(Kshs/kg N) conditional on plot soil carbon content*
*Marenya, P.P. and C.B. Barrett (2009) State-conditional Fertilizer Yield Response on Western Kenyan Farmers; Amer. J. Agr. Econ. 91(4)
(November 2009): 991–1006
*Marenya, P. P., C. B. Barrett (2009) Soil quality and fertilizer use rates among smallholder farmers in western Kenya; Amer. J. Agr. Econ.
91(4) (November 2009): 991–1006

7. Addressing Biophysical
Challenges
Producers use practices and systems that do the following:
1. Reduce rainfall run-off and increase infiltration
2. Build up soil organic matter
– Increases soil’s moisture retention capacity in crop’s root zone
(retains up to 90% of its weight in moisture)*
– Increases soil’s fertilizer-use efficiency
1. Use fertilizers and improved seed in tandem with above
2. Diversify farming systems to include crops less
vulnerable to drought and other shocks (e.g., tree crops
in a mixed annual-perennial system) and avoid selling
productive assets in order to eat!!
*Wood, Sebastian, Scherr (2000) Pilot Analysis of Global Ecosystems—Agroecological Systems; World Resources
Institute

8. Soil Organic Matter By
Continents
“Africa is the world's most ancient land mass.” Breman
While Increasing Fertilizer Use in Dryland Africa is
Essential, increasing SOM is Essential for FUE

9. Reducing Runoff and
Reclaiming Land at Scale
Central Plateau, Burkina Faso: 200,000 ha.
Tahoua Region, Niger 100,000 ha
Reij, C., G. Tappan, M. Smale (2009) Agroenvironmental Transformation in the Sahel:
Another Kind of “Green Revolution; IFPRI Discussion Paper 00914, November 2009;
Prepared for the Project, Millions Fed: Proven Successes in Agricultural Development
Djenne, Mali, Chris Reij, 2008

10. Sorgho
“Sustainable Intensification”:
Microdose in Tandem with Zai’s
Millet: One week after seeding—
Early establishment correlated to
higher yields
Sorghum
Treatment Yields
Control 0 to 400 kg/ha
Zai + microdose 900 kg to 2000 kg/ha
SAWADOGO H. and Barro, A. POLITIQUES DE RECUPERATION DES TERRES DEGRADEES AU BURKINA FASO: BILAN
ET PERSPECTIVES ; Power Point Presentation, Février 2012 ; INRAN, Burkina Faso

11. Ridge Tillage in Mali: Increasing
Rainfall-use Efficiency
Increased:
•Infiltration by 66%
•Average Soil moisture by 17% but 39% in
the 20-40 cm zone at end of season
•Soil C by 12-26%
•Fertilizer-use Efficiency by 30%
«
• 30-50% yield increase
• Water table recharged
-Doumbia, M. (2008) Sequestration of organic carbon in West African soils by Aménagement en Courbes de Niveau Agron.
Sustain. Dev., 2008
-Kablan, R. et.al, (2008) '"Aménagement en courbes de niveau," Increasing Rainfall Capture, Storage, and Drainage in Soils of
Mali', Arid Land Research and Management, 22:1, 62 – 80

12. Dry Season Gardens: A Dividend
of Rainwater Management
• Higher water table
allows dry season
irrigation;
• Higher prices for
counter-season
produce;
• New and additional
sources of revenue
and nutritious foods.
• Resilience
Strengthened
Sorofin Diarra irrigates her garden while daughters Batama, Youma and Nieba observe. Currently, 80%
of Siguidolo households have gardens compared to one before ACN was introduced12 years ago .
(ACN Brochure, Soils Management CRSP)

13. REJUVENATED LAND: Dr. Doumbia (left) and farmer Zan Diarra observe a baobab
tree that regenerated following the establishment of ACN.
High-Value Field Trees: Additional
Dividend of Rainfall Management

14. Weathered Soils & Integrated Soil
Fertility Management (ISFM)
ISFM: “combined use of locally-available organic resources
and the judicious use of mineral fertilizer …”
Farmers’ practices After 4 yrs of ISFM
Cereal Yield* VCR**
Fertilizers
Cereal Yield VCR Fertilizers
Maize; outlying
field
750 --*** 2,750 4
Maize;
compound
3,000 --*** 4,600 12
Sorghum 1,000 --*** 2,000 8
Cotton 1,150 5 2,000 8
*kg/ha; **Incremental value/fertilizer cost; ***No fertilizer used
H. Breman, A. Gakou, A. Mando and M. Wopereis (2004) Enhancing Integrated Soil Fertility Management Through the
Carbon Market to Combat Resources Degradation in Overpopulated Sahelian Countries; Regional Scientific Workshop
on Land Management for Carbon Sequestration; Bamako (Mali), February 27-28, 2004

15. ISFM Principles Applied Over
Time
*Source: Sedogo (1993); Bationo, “Technologies for sustainable management of sandy Sahelian soils,” in FAO,
“Management of tropical sandy soils for sustainable agriculture.”
**Wopereis, M., A. Mando, B. Vanlauwe Agro-ecological principles of integrated soil fertility management – a guide with
special reference to sub-Saharan Africa;mIFDC Technical Bulletin Series
•“Treatments using only
inorganic fertilizer often show a
decline in yield after time….”
•Acidification
•SOM decline
• Soil organic matter improves
• Cation exchange (CEC)
• Water retention capacity
• Soil structure.**
Sorghum grain yield as affected by
mineral and organic fertilizers over
time.*

16. ISFM: Challenges of Soil Organic
Matter
Nyankpala region (Northern Ghana): Compost heap (after a
practical class by researchers from SARI and development workers
from MoFA)

17. Mature Faidherbia albida Parkland: Peanut
Basin, Senegal (Tappan)
•Soil Carbon: Increase between 40% and 269%*
•Cation-Exchange Capacity (CEC): 120% increase
•Soil-water Holding Capacity: Significant Increase
•Microbial activity: Significant Increase
•Yields: Increased from 500 (+/- 200) to 900 kg/ha (+/- 200)
“State of the Art: Acacia albida,” Peter Felker, 1974
FMNR: Source of Soil Organic
Matter and Other Benefits

18. Diversified Systems to Sustain
Productivity and Build Resiliency
Animal fattening operation based primarily on pods
from field trees

19. Diversified Systems to Sustain
Productivity and Build Resiliency
Fuel Wood and Construction Poles

20. A Conclusion
• Based on current evidence, many farmers in dryland
Africa can double or triple yields, in a cost-effective
and sustainable manner, and can strengthen
resilience by
– Investing in fertilizers and improved seeds in tandem with
practices that increase rainfall and fertilizer-use efficiencies
and
– Diversifying their production systems to include crops and
sources of livelihoods that are less vulnerable to climatic and
market shocks than annual staples.

21. Doubled-up legume systems

22. Multiple benefits from perennial pigeonpea
(P.P.) shrub-diversified maize
Snapp et al. 2010 PNAS
P.P. + ½ F