building resilience to climate change in malawi trends in crop yields under ca and factors affecting...
TRANSCRIPT
Building Resilience to Climate Change in Malawi: Trends in Crop Yields under
CA and Factors Affecting Adoption
Prepared by Total LandCare and CIMMYT
CA Congress, Zambia Mar 18-22, 2014
Bunderson, W.T. 1, Thierfelder, C.2, Jere, Z.D. 1, Gama, M.3, Museka, R., 1Ng’oma, S.W.D. 1, Paul,
J.M. 1, Mwale, B.M. 1 and Chisui, J.L.1
• TLC began a serious program on Conservation Agriculture in 2005 through a program of collaboration with CIMMYT and the Min of Agriculture. A key aim is to document the benefits of CA versus conventional ridge tillage in different agro-ecologies to provide a foundation for promoting CA across Malawi.
• The first part of this presentation will briefly describe TLC’s development philosophy and extension approach.
• The second part will summarize key results and findings from long term on-farm trials with CA.
• The third part will focus on TLC’s experiences and challenges with promoting CA in Malawi.
Focus of Presentation
3
TLC’s Development Philosophy
● TLC’s mission is to improve the livelihoods of rural communities through a
community focus that instills ownership and responsibility in addressing
priority needs to increase food security, productivity and incomes on a
sustainable basis with greater resilience to climate change.
● Fundamental to this mission is to empower communities with the knowledge,
skills and resources to become self-sufficient under the philosophy of “giving
a hand-up, not a hand-out”.
● TLC’s community focus is “all inclusive” to benefit all members of the
community without discrimination as to social status, income, gender,
background, religion or ability. Special efforts are made to include those
sidelined by social distinctions, e.g., women, HIV/AIDS, physical challenges.
● Extension services focus on a diverse range of “proven” interventions to
address multiple needs which create synergies for sustainability and impact.
4
TLC Extension Approach ● Selection of sites and communities is coordinated with the District
Executive Committee, local leaders and other stakeholders based on
participatory assessments to prioritize needs and opportunities.
● Thereafter, community-based action plans are developed with clearly
defined roles and responsibilities of the beneficiaries, local leaders,
TLC, Govt extension agencies and other service providers.
● Agreed actions are facilitated through a network of Field Coordinators
(FCs), Community Extension Workers (CEWs) and Lead Farmers to
deliver quality training and extension services under the direction of
centrally placed field offices in different regions of the country.
● Experiences and lessons with farmers are monitored and evaluated
regularly through a robust community-based M&E system to improve
efficiency and effectiveness.
CA System Promoted by TLC ● Minimum soil disturbance (mandatory)
No ridging or tillage by manual or mechanical means
Direct sowing into a) small planting holes on the flat or tops of old ridges using a hand-hoe, dibble stick or jab-planter, b) planting basins 35 cm long x 15 wide x 20 deep, or c) rip lines opened by animal drawn rippers
● Retention of crop residues or other plant biomass on the soil surface (whenever this is feasible and practical)
● Crop rotations, associations and agroforestry (whenever possible given the limited land holdings of most smallholders)
● Quality seed & fertilizers maximize the potential of CA (when available and accessible)
● Herbicides reduce soil disturbance and competition from weeds with lower labor & input costs (when available and accessible)
Conventional Ridges built with Hand-Hoes
Labor and Soil Moved for Ridging
Avg Soil moved in forming 1 m of ridge= 50 kg
• Malawi smallholders ridge about 2 million ha per year.
• With a ridge spacing of 90 cm, the soil moved every year averages 500 tons / ha.
• This means that Malawi farmers build over 22 million km of new ridges every year which requires moving over 1000 million tons of soil.
CA Planting Holes: Planting holes prepared with hoes on alluvial soils which were
formerly ridged manually with hand-hoes
Retention of Crop Residues on the Surface
Safe and proper use of herbicides to control weeds at planting time
Uniform stand of young, weed-free maize planted on old ridges with crop residues & use of herbicides
Integration of Faidherbia albida with CA: Studies have recorded increased maize yields of 50-200% through improvements in soil fertility and the micro-environment which greatly enhance resilience to climate change
CA with zero tillage and crop residues spread evenly between vetiver hedges on slopes
Conventional Ridge Tillage vs. CA
Ridged land shows runoff & standing water in the
compacted furrows; tied ridges were built to reduce runoff &
loss of top soil
CA with crop residues in adjacent plot on same date and time: excellent infiltration with no sign of runoff or loss of top
On-Farm Results with Farmers: 2005/06 to 2012/13
• Long term on-farm trials were established to
compare 2 CA plots with conventional ridge tillage in
up to 12 different communities, each with 6 farmers.
• From the year of establishment, each trial has been
maintained to evaluate long term benefits and
impacts in terms of yields, soil properties, economic
returns and labor costs.
Treatments
CRT Maize: Conventional ridge tillage & land clearing using hand-hoes for ridging, planting and weeding
CA Maize Sole Crop: Crop residues spread & retained on the surface; direct sowing with dibble sticks on the flat or old ridges, weed control with pre & post emergent herbicides
CA Maize + Cowpea/ P Pea Intercrop: Crop residues spread & retained on the surface; direct sowing with dibble sticks on the flat or old ridges, weed control with round-up only
Agronomy ● Trials planted in up to 12 target communities with
replicates of 6 farms per community
● Maize planted at 75cm x 25cm (53,300 plants/ha)
● All plots were 0.1 ha in size
● Fertilizer was applied uniformly across treatments at 69N:21P205:4S as basal and top-dressing
● Crop varieties used were uniform within communities
● Residues at least 3t/ha before the onset of rain
Agronomy - continued
● Intercrops on treatment 3: cowpeas in central Malawi and pigeon peas in southern Malawi
● From 2011/12 trials included full rotations of maize-groundnuts & maize - pigeon peas
● Advantages of planting legume crops under CA:
Legume crops can be grown at closer row spacing (37.5cm) than with ridges which increases much higher yields
Closer spacing also provides much better groundcover to reduce runoff and loss of top soil
Maize yields across years in up to 12 communities (p significant between CRT and CA except 2005/06)
0
1 000
2 000
3 000
4 000
5 000
6 000
2005/06 2006/07 2007/08 2008/09 2009/10 2010/11 2011/12 2012/13 Mean
Kg
/ha
CRT-Mz CA-Mz CA-Mz+Leg
N=24 N=36 N=54
N=48
N=54
N=396 N=54
N=54 N=72
Maize yields in 9 communities in a dry year, 2011/12 (Yield increase 64% & 70% - p significant)
2 485
4 086 4 224
0
1 000
2 000
3 000
4 000
5 000
6 000
7 000
Kg
/ h
a
CRT-Mz CA-Mz CA-Mz+Leg
Maize yields in 12 communities, normal year (2012/13) Yield increase of 35% & 42% - p significant all sites
3 129
4 222 4 421
0
1 000
2 000
3 000
4 000
5 000
6 000
7 000
8 000
9 000
Kg/
ha
CRT-Mz CA-Mz CA-Mz+Leg
Groundnut yields in 6 communities, Malawi 2012/13 Yield increases of 122% - p all significant except Zidyana
658
1 463 1 470
0
500
1 000
1 500
2 000
2 500
3 000
Chipeni Mwansambo Zidyana Lemu Linga Chinguluwe Mean
Kg
/ha
CRT-Mz CA-Mz
CA-Mz+Leg
Communities
Summary of yields under CA vs. CRT
• Results clearly show the superiority of CA vs. CRT with significant increases in maize yields for all sites after year 1.
• Planting intercrops showed no negative effects on maize and provides a higher return to land, labour and capital from a 2nd crop on the same land.
• Yield increases of maize ranged from 11% to 70% across years with greater increases in years of low rainfall.
• Farmers realized higher yields of groundnuts under CA because of the closer row spacing which is not possible with ridging.
• Closer spacing of groundnuts increased the ground cover significantly which will help to reduce runoff, loss of top soil and rosette disease.
Over all result: Higher and more stable yields of cereals and legumes will benefit households in terms of improved food security, nutrition and
income to increase their resilience to climate change.
TLC Experiences in Promoting CA
2005/06
2006/07
2007/08
2008/09
2009/10
2010/11
2011/12
2012/13
Farmers Trained in CA 321 585 799 2 879 5 827 23 706 27 000 35 197
Farmers Practicing CA 46 114 591 2 067 3 924 6 634 10 645 17 797
Ha under CA 14 34 236 499 1 275 2 704 5 461 5 865
-
1 000
2 000
3 000
4 000
5 000
6 000
7 000
-
5 000
10 000
15 000
20 000
25 000
30 000
35 000
40 000
# Ha
# Farmers
Farmers Trained and Practicing CA, 2005/06 to 2012/13
2005/06 2006/07 2007/08 2008/09 2009/10 2010/11 2011/12 2012/13
Male Farmers 34 80 413 1 369 2 630 4 799 7 194 11 199
Female Farmers 12 34 178 698 1 294 1 835 3 451 6 598
-
2 000
4 000
6 000
8 000
10 000
12 000
# F
arm
ers
Gender of Farmers Practicing CA
2005/06 to 2012/13
Note: Gender breakdown is based on
who signed for Inputs, but in reality,
women take the lead in undertaking CA
and clearly will be instrumental in
efforts to scale up CA
Observed Benefits of CA
Farmer surveys revealed several key benefits of CA:
● Significant savings in labor for land preparation, ridging, weeding and banking.
● Increased yields, especially in years of poor rainfall, which farmers related to moisture conservation.
● Reduced loss of top soil was evident in fields from low runoff.
Farmer Interviews on Factors Affecting Adoption
785 households were randomly sampled across 14 different sites under 4 different projects
Interviews involved 438 men and 347 women
The number of farmers adopting CA was low relative to the number trained or exposed to CA
Results revealed that 335 farmers (47%) were practicing CA, 12% had tried and stopped, and 40 % never tried CA
Key Factors Affecting Adoption of Farmers Practicing CA
Key Constraint No.
Farmers
% of Sample
Lack of information or conflicting messages 144 43%
Resistance to change (from traditional ridging and land clearing)
76 23%
Poor understanding of herbicides & their use 10 3%
Lack of inputs and crop residues & related labour to gather and spread crop residues over the field
105 31%
Total 335 100%
Reasons for Dropping CA
Factors for dropping practicing CA No.
Farmers
% of Sample
Resistance to change from traditional farming 4 4%
Problems with applying herbicides 24 22%
No access to inputs or limited crop residues/biomass
67 62%
Inadequate knowledge about CA / poor extension services
13 12%
Total 108 100%
Key Challenges to Adoption 1. Breaking the deep-rooted culture of ridging and tradition
that fields must be clean of all plant biomass, living or dead.
2. Lack of clear evidence of the benefits of CA and that it can be used successfully with other major crops, i.e., not limited to maize and groundnuts.
3. Delivery of inconsistent and conflicting technical messages on CA by different organizations creates confusion among both staff and farmers with impacts on the benefits.
4. Perceptions among farmers and extension staff that specific inputs and/or tools are needed to undertake CA (e.g., fertilizers, herbicides, large amounts of crop residues, etc).
Key Actions to Address Challenges ● Strengthen knowledge and support for CA among all
stakeholders and clarify what it really means with compelling evidence of its benefits and application with major crops across different agro-ecologies.
● Harmonize technical messages among implementers to avoid distorting the basic concept of CA and its benefits and confusing extension staff and farmers.
● Facilitate access to basic inputs and tools by farmers.
Note: The issue of inputs has raised a dilemma: how to balance the need for inputs (to maximise and demonstrate the potential of CA as a new technology) with the risk of that CA will become
input-driven, which may limit adoption.
Confusion about the meaning of CA
It is clear that CA is not well understood by implementers, NGOs, projects, extension agents and farmers.
● For example, the definition of CA as comprising 3 core principles has been interpreted to mean that undertaking any of them qualifies as CA. The diagram to describe CA in this way has been changed to avoid this problem (see the 2 diagrams below).
● Another good example is the distortion of making small planting basins to excavating deep pits (see photos below).
Good Soil CoverMinimal Soil
Disturbance
Crop Rotations /
Crop Associations
Growing Crops in the Field No Ploughing / TillageBalanced 3 or 4 Way
Rotations
No Ridging
No Banking
No Burning of weeds or crop
residuesNo Pitting Intercropping / Associations
Organic ManuresContour Vetiver
HedgesAgroforestry Practices
Chemical
FertilizersSelected Herbicides
Improve soil structure &
fertility
Reduce runoff &
erosion
Improve soil structure &
fertility with provision of
wood & other products
Complement
other practices to
improve soil
fertility
Complement use of surface
mulch to control weeds with
reduced labor costs
Complementary Practices
CORE PRINCIPLES OF CONSERVATION
AGRICULTURE
Surface distribution of crop
residues & cut weeds2-way / Partial Rotations
Core Principles of Conservation Agriculture and Complementary Practices
CORE PRINCIPLES OF CONSERVATION AGRICULTURE AND COMPLEMENTARY PRACTICES
Minimal Soil Disturbance
No Ploughing
No Tilling
No Ridging
No Banking
Good Soil Cover
Growing Crops
Crop Residues & Other Plant Biomass
No Burning
Organic Manures
Compost
Animal Manures
Green Manures
Crop Rotations / Crop Associations
Full & Partial Rotations
Intercropping / Associations
Methods & Tools for Planting
Dibble Sticks
Chaka Hoes
Rippers
Other Soil & Water Conservation Measures
Contour Vetiver Hedges
Raised Foot-Paths
Storm Drains
Agroforestry
Soil Fertility
Ground Cover
Wood Products/Uses
Herbicides
Weed Control withIncreased Yields
Conservation of soil nutrients and moisture
Chemical Fertilizers
Soil Fertility
Increased Yields& Ground Cover
CA Planting Basins (CFU Zambia) Planting basins are a one-off operation to help capture
water and/or to break hoe pans
Distortion of the Concept of Planting Basins Pitting as shown below is promoted by some
organizations but this is NOT CA (Note the heap of top soil next to the pits on the right)
Left Photo by T Bunderson, right photo from CFU
THANK YOU FOR LISTENING