improving agricultural productivity in the rural-urban interface: lessons for soil fertility...
DESCRIPTION
Soil fertility & agricultural productivity in SSA,SSA Agriculture - the rural-urban interface,Nutrient recycling in peri-urban agricultureTRANSCRIPT
Improving agricultural productivity in
the rural-urban interface: Lessons for
Soil fertility research at IITA
Olufunke Cofie (PhD)
Candidate for the position of Soil Fertility Specialist
Outline
• Soil fertility & agricultural productivity in SSA
• SSA Agriculture - the rural-urban interface
• Nutrient recycling in peri-urban agriculture
• Lessons for IITA Soils Research
• Conclusions
Low agricultural productivity in SSA• Low inherent fertility
• Nutrient depletion
• Low per capital fertilizer use
• Low yieldLow
Investments
Low yieldLow
Income
…a cycle
The low performance of agriculture is the main
cause of its slow economic growth
It is the only region of the world where per capita
food production has been declining for the past
three decades
Cereal Yields in Developing Regions 1960-2005
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
1960 1965 1970 1975 1980 1985 1990 1995 2000 2005
Sub-Saharan Africa
South AsiaLatin America
East and Southeast Asia
Source: FAOSTAT.
mt/
ha
Nutrient Mining of Agricultural Land in Africa
(kg/ha/yr)1995-97 2002-04
Source:
IFDC
- Africa loses $4billion/yr in soil nutrients
Netherlands
Vietnam
Japan
UK
China
France
Brazil
USA
India
South Africa
Cuba
Benin
Malawi
Ethiopia
Mali
Burkina Faso
Nigeria
Tanzania
Mozambique
Guinea
Ghana
Uganda
Source: FAOSTAT, from Borlaug, 2004
100 200 300 400
Fertilizer nutrient consumption per hectare of arable land in selected countries, 2002
(kg/ha)
50060
0
0
50
100
150
200
250
300
350
400
450
1930 1940 1950 1960 1970 1980 1990 2000 2010 2020
Total
Population
Urban
Population
Rural
Population
Urbanization in West Africa
(in millions)
Urban population is becoming as large as the rural.
Agriculture in the rural-urban interface
• contributes to inner-urban food supply,
• compensates for missing cool transport and
storage (required for perishable crops),
• provides jobs, income and livelihoods.
• provides opportunity for closing rural-urban
nutrient flows
Contribution of UPA to urban food supply
0
20
40
60
80
100
UA PUA RA UA PUA RA UA PUA RA
Accra Kumasi Ouagadougou
City and source of food
% c
on
trib
uti
on
to s
pec
ific
food
ite
m
Pineapple Cabbage Lettuce Spring onion Garden egg Tomatoes
Urban centres are nutrient sink
• Provides opportunity for nutrient
recycling
• Closing the nutrient loop
• Enhance intensive agriculture in the
peri-urban
The fertilization equivalent of untreated organic solid waste
Nutrient Contribution in kg / cap
year
Nitrogen (as N) 0.55 – 1.1
Phosphorus (as P) 0.2 – 0.4
Potassium (as K) 0.55
Carbon (as C) 16 – 22
Resources in excreta
Nutrient in kg / cap year
Nutrient In urine
(500 l/year)
In faeces
(50 l/year)
Total Required for
250 kg of cereals 1
Nitrogen (as N) 4.0 0.5 4.5 5.6
Phosphorus (as P) 0.4 0.2 0.6 0.7
Potassium (as K) 0.9 0.3 1.2 1.2
Carbon (as C) 2 2.9 8.8 11.7
1 = the yearly food equivalent required for one person
2 = indicative of the potential for soil conditioning, normally not designated a nu-
trient
Nutrient value of Excreta is high enough to produce
food BUT with health risks !!!
Adequate processing reduce health risk
Dynamics of Ascaris eggs viability reduction during co-composing of faecal
sludge and organic solids waste
Quality
parameter
(Unit)
Concentration
N (g/kg) 11.9 2.3
P (g/kg) 16.2 4.8
K (g/kg) 17.0 4.7
Ca (g/kg) 35.1 8.7
Mg (g/kg) 7.9 2.0
Pb (mg/kg) 28 28
Cd (mg/kg) 0.4 0.1
•Free from toxic heavy metals
Co-compost
cumulative inflitration -Tuu tengli
10.07.2003
y = 8.3846Ln(x) - 7.1975
y = 2.6036Ln(x) - 3.3556
0
5
10
15
20
25
30
35
40
0 20 40 60 80 100 120
time (minutes)
dep
th
(cm
)
Faecal Sludge treatment control
Comparison of economic benefits between users’ and non-users’ of excreta
application on farmlands in Krobo District, Ghana
Variable Users Cost/ ha ($) Non-users Cost / ha ($)
Total revenue 918.56 606.54
Land Preparation 72.38 54.64
Hired labour 178.83 189.42
Seeds 10.32 7.71
Excreta / Fertilizer1 18.79 51.23
Chemicals 34.00 19.74
Total Variable Cost 314.32 322.74
Gross Margin 604.24 283.80
Fixed Cost 0.00 0.00
Depreciation 7.65 7.87
Family labour 112.21 80.37
Rent on land 70.90 48.22
Total Fixed cost 190.76 136.46
Net Income 413.47 147.35
1 Excreta apply to users whilst fertilizer apply to nonusers. The cost incurred on
excreta is for transporting the excreta to farm site. Source: Cofie et al 2007
Communicating results
• Publications in several outlets
– Refereed journals
– International conferences
– Book chapters
– Newsletters
Partnerships
• ARI – EAWAG, NRI, IHE-UNESCO
• NARES – Ghana, Nigeria and Sierra Leone
• Policy makers
• Farmer organisations
• NGOs
• Private Sector
Networking
• International Network of Resource Centres
on urban agriculture and food security-
Regional Coordinator
• SWITCH consortium – Chair
• SWISS NCCR – Senior member
Paradigm Shift Required
• From management of part of soil resource base
- Nutrient Cycle Management.
• From single use of resources
- Recycling and Integrated organo-mineral cum
cultural management practices
• From disregard of soil resource base
- fertility-sensitive farming practices
Lessons for IITA Soils Research
Involving other stakeholders
• Involving the necessary people through multi-stakeholder processes and platforms:– Government Agency/Ministry– Funding Agency – Metropolitan Authorities– NGO’s – The private sector– Media– User Groups/associations– Emerging initiatives – AGRA etc
• Coupled with social processes to move sustainable resource management across the research-policy-implementation interfaces
Given these experiences, it should possible to
transform the soil fertility research for
development in IITA.
Conclusion