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Jean marc presentation 13th october
1. Shade coffee in East Africa:
What’s in it for farmers and biodiversity?
Jean-Marc Boffa
2. Background: Global coffee sector
• Decline of world prices (25% of 1960 prices in real terms)
• Oversupply and stagnant consumption
• Market deregulation (breakdown of quality control, input systems on
credit, coffee quality)
• Trading and roasting segments more concentrated and capture
higher proportion of profits
• Farmers get a declining share of coffee market value
• Quality, a secure investment for restoring value
• Growing specialty coffee segment, 17% of volume and 40% of value
of US coffee market
3. Coffee in East Africa
• Rapid development from 1930s to 1980s (new cultivars, state
intervention, abundant land). 24% of African exports in mid 1980s
• Global coffee crisis, liberalization of coffee sector, age and
productivity decline of coffee plantations. 11% of African exports
in late 1990s
• Coffee >50% of current export earnings in Burundi, Democratic
Republic of Congo, Ethiopia, Rwanda and Uganda. 30%, 3rd
export crop in Kenya.
• East and Central Africa is 4th largest growing area; estimated 1.2
million farmers and 4 million ha of land
• Growing interest in and development potential of East African
coffee renowned for its natural quality
4. Why an interest in shade coffee?
• Small landholdings, declining soil fertility,
labor scarcity, unaffordable inputs.
Intensive production models unfit for
smallholder systems.
• Need for higher profitability, income
stability, lower risk through
diversification, environmental
friendliness, and enhanced quality for
the market.
• Renewed interest on shade systems and
their contributions to coffee quality and
profitability, environmental sustainability,
and diversification.
5. Outline of presentation
1. Impact of tree shade on coffee production
2. Relations between shade and coffee quality
3. Potential benefits of shade coffee for smallholders in
East Africa
4. Shade coffee and biodiversity conservation
Not covered are issues of carbon sequestration and
water
6. Coffee’s native habitat
• Naturally found as under/midstorey forest plant
• Coffea arabica, understory shrub in • Coffea canephora, midstorey tree,
Ethiopian tropical montane forests lowland Congo river basin,
• 1600-2800m; mean 20ºC; 1600-2000mm • 0-1200 m altitude, mean 25ºC, rainfall up
rainfall; to over 2000 mm over 9-10 months and
• 3-4 month dry cool season high constant air humidity
• Does not tolerate high temperatures and • Does not well in low temperatures
humidity
• Recommended conditions (DaMatta, 2004)
Coffea arabica Coffea canephora
• 18-21ºC • 22-30ºC
• 1200-1800mm rainfall • 1200-1800 mm rainfall, > 2000 mm
• >1000 m altitude, deep soils, >2000 mm rainfall, 4-mo. dry season,
wind protection (Vaast and Harmand, 2002)
• Divergence on lower range between authors/countries
• Frequently grown outside these recommended intervals
7. Controversy on shade
• The use of shade has been questioned and researched since the
beginning of its cultivation.
• Initially grown under or close to forest cover. Originally thought
indispensable to coffee growing in mid altitudes in the tropics
• Successful fun sun experiments with intensive management followed by
massive promotion programs
• Breeding of modern cultivars adapted to sun. 40% of Middle America,
Caribbean and Columbia coffee is in full sun
Optimal conditions
• Removal of shade increases coffee yields (several authors)
• 45% artificial shade reduces 3-year cumulative production of fertilized
coffee by 18% (Vaast et al, 2006)
• Often decline in coffee quality
Suboptimal conditions (low altitudes, higher temperatures)
• 3-year cumulated fertilized coffee yielded 16% and 49% less in full sun
than under Terminalia ivoriensis (dense shade) and Eucalyptus deglupta
(light shade) respectively in suboptimal conditions (Vaast et al, 2006)
8. sh
ad
e
• Small or no response to fertilizers
High response to fertilizers -> Reduces photosynthesis and
-> Light is limiting factor metabolism
Higher no. of flower buds per node • Reduced flower induction
Higher no. of coffee nodes per branch • Longer internodes
Reduced branch length • Lower number of fruiting nodes
• Higher vegetative growth
Heat stress of plant and faster leaf – lower no. of leaves per branch
senescence and fall but
– larger leaf area
• Higher leaf to fruit ratio
• Longer life span of leaves
9. sh
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e
Increased flowering and fruiting
Sink effect Lower fruit loads
Resources going to seeds Fewer nodes but higher final berry
•Increased fruit drop load per node bec. lower berry drop
•Reduced maturation period Longer maturation period
•Smaller bean size Larger bean size
Reduced shoot elongation and branch weight Balanced of fruit and vegetative
Reduced production potential the outputs
following year. Weakened plant and Reduced variations in alternate
dieback. Biennial /alternate bearing
bearing
10. Productive soils Poor soils
yield yield
shaded
unshaded shaded
unshaded
Low optimum high Low optimum high
elevation elevation
Source: Beer et al., 1998
Fertilized yields 1800-3000 kg/ha Fertilized yields 300-1800 kg/ha
Shade reduces photosynthesis, transpiration, metabolism and growth and therefore,
the demand on soil nutrients and so enables crop to be obtained on soils of lower
fertility. (Purseglove 1968)
Influence of tree density on yields through underground competition. Optimal
densities varies according to site and species.
11. Impact on pests, diseases and weeds
• Varies according to individual organisms and their response to
increased humidity and reduced light under shade
• Lowers diffusion of coffee berry disease by reducing splashing
and free water
• More pronounced attacks by coffee leaf rust (Hemileia vastatrix).
Major reason for the early promotion of tree shade removal
• Reduces defoliation by brown-eye-spot (Cercospora coffeicola)
• Higher incidence of the dry season coffee berry borer
(Hypothenemus hampei)
• Stabilize coffee nematodes or increase coffee tolerance to
nematode infestation if shade trees are not hosts
• Pest regulation by a range of arthropods as natural enemies of
insect coffee pests
• Reduces weed biomass considerably. Aggressive grasses ->
broadleaf types. Savings in costs of weeding>tree management
costs.
12. Coffee quality under shade
• Reduction in light exposure
and temperature
• Slower and longer berry
maturation period
• Better bean filling and higher
sucrose accumulation
• Larger bean size. Price
determinant at farm gate
13. Effect of shade on coffee quality chemical and
organoleptic characteristics
Authors Avelino Vaast et al Vaast et al Muschler 01 Guyot et
et al 03 06a 06b al 96
Conditions Optimal Suboptimal Suboptimal Optimal
Years 1999 2000 2001 2002 Catimor Caturra
Total acidity +
Caffeine + + + + +
Fat + + + + same
Sucrose - - +
Chlorogenic - - - - +
acids
Trigonelline - - - - -
Body - - - - + + same
Bitterness - - - - -
Astringency - - - - same
Acidity + + + + + + same same
Aroma - same same
Preference + + + +
By reducing flowering intensity and productivity, shade consistently leads to
enhanced beverage quality in both favorable and unfavorable ecological conditions
14. Potential benefits for East African smallholder farmers
Coffee
• Potential increase in coffee yields, generally in
suboptimal conditions
• Better quality coffee
• Reduced damage by hail and rain storms
• Reduced occurrence of some pests and diseases
• Longevity of coffee plants reduces need to replant
Soils
• Provision of soil mulch (moisture and fertility, weed
suppression)
• Aeration and drainage of soil for intercrops
• Reduced soil erosion on slopes
• Enhanced soil fertility (recycling of deep nutrients
and nitrogen fixation)
15. Potential benefits for East African smallholder farmers
Management
• Reduced weeding costs
• If compared to full sun systems, can it reduce labor costs?
• More efficient use of labor and machinery with more
constant interannual production for harvesting and
processing.
• More constant volume and quality of coffee supplies to
buyers
Diversification in farm production
• Alternate income and security from diversity of marketable
products (timber, fruits, fodder, fiber, etc).
– Fruit and timber=60% and 3% of farm income in
Venezuela (Escalante et al., 87)
– Shade tree products=28% and 19% of coffee income in
Peru and Guatemala (Somarriba et al., 04)
– 42% farmers market timber and fuelwood products in E.
Mt Kenya; $35 per year (Holding et al, 06)
• Service wood and other non necessarily marketed products
+ food crops
16. Some disadvantages of shade coffee
• Damage by fallen branches to the coffee crop
• Additional labor for tree pruning
• Mechanization hampered by trees
• Implementation of soil erosion measures rendered
difficult by trees
• Poor shade adaptation of newly bred cultivars
• Coffee-tree competition
• Increased occurrence of specific pests and diseases with
increased humidity
• Allelopathy
• Trees providing alternate hosts for coffee pests and
diseases
• Erosion, crop damage and reduced water absorption in
soil by leaf drip damage
17. Implications for East Africa
• Most studies originate from C. and S.
America. Limited data on condition
of coffee system
• Characterization and mapping of
shade coffee systems in East Africa.
• Comparative coffee shade versus
sun studies to better define the
potential of shade in East Africa
Central Province of Kenya
• What areas have optimal and sub-
optimal conditions in East Africa?
• Where and how significant is impact
of shade on production and quality?
• How much shade? Is it sufficient to
make a difference?
• Large contribution of smallholder
farming, that includes a diverse tree
cover by default. Document,
validate, refine recommendation
domains
• Varies by country
18. Estimates
• Kenya: 50% large full sun
industrial plantations-50%
smallholder farms
• Rwanda: Heavy traditional
promotion of coffee growing
in full sun (ACDI-VOCA)
• Tanzania: 20% industrial
plantations-80% smallholders
• Uganda: 99% smallholder
systems
19. Shade coffee and biodiversity conservation
• Agricultural system with great potential to conserve
biodiversity. Structural diversity and vegetation
complexity of original forest vegetation it is derived from.
• 2nd largest traded natural commodity after oil, has a
major economic importance for livelihoods and national
export revenues.
• Quantitative vs. location: 15/34 hotspots located in coffee
regions
• Areas of intense deforestation where shade coffee may be
only remnant vegetation
• Major opportunity for combining conservation and
economic improvement
20. Conservation potential of shade coffee
• Largely emphasized in Central and N.
Latin America as habitat for migratory
birds through Mesoamerican Biological
Corridor
• Varies according to management
types, complexity providing food,
shelter and reproduction
• Species dependent on trees for their
life cycle vs. species that rely on
fragmented forest habitat in wider
landscape
• Most often lower bird species richness
than primary forest and different
composition
• Rustic systems may host similar or
higher bird diversity, especially for
winter migrants with flexible habitat
needs
21. Shade coffee and biodiversity conservation
in East Africa
• Not a similar regional corridor function
• Contribution to conservation of
European migrants not emphasized
• Relatively limited information in East
Africa
• Naidoo 04, bird richness correlated to
tree density and distance to intact
forest in Mabira, Southern Uganda.
Limited contribution of coffee-banana
systems to conservation of forest-
dependent songbird species
• Soini 06, tree cover reduction and
fragmentation, highland homegardens
with coffee-banana and large trees
more bird-diverse than lowland and
midland systems. European-style
highland richest due to high niche
diversity and lower human
disturbance of shrub layer
22. Mabira Forest banana-coffee landscape,
Southern Uganda
Ordination of the 96 stations obtained from a Detrended Correspondence Analysis of
the species composition of bird communities.
primary
160
secondary
140 agro
120
Distance between
100
stations
80 indicates degree of
60 similarity in bird
community
40
composition
20
0
0 100 200 300 400
Number of species primary=secondary>agro
23. Factors enhancing conservation value
Coffee plantation characteristics
• Structural complexity (habitat) and
floristic composition (food sources)
• Plantation management intensity
(thinning, pollarding, fertilizers)
• Vertical canopy thickness, coffee
height and presence of epiphytes for
butterfly diversity
Landscape factors Source: Turyomurugyendo
• Overall landscape degradation
• Landscape characteristics
– Number and size of forest fragments
– Distance and connectivity to forest
patches (mobile vs less mobile spp)
• Forest management policy. Hard edges
in East Africa for segregating land
uses, reducing h-w conflicts, easier
enforcement of restrictions
26. Wild forest coffee in Ethiopia
• Focus on conserving the Arabica
center of endemism
• Wild coffee forests, transformation
of undisturbed coffee forest to semi-
forest coffee
– Removal of overstorey trees and
shrubs
– Increase of 26% of plant species
(disturbance-adapted)
• 25% of national coffee production
Pressures
• Internal and government-planned
resettlement for Northerners
• Land conversion for agriculture and
settlement
• Demand for forest products
Potential and current forest cover
27. Shade coffee certification and conservation
• Markets of shade-grown coffee appear
important for providing a reward for
conservation
• Caution: encouraging primary forest
conversion; lowering of standards; blanket
endorsement of all shade systems
• Challenge of ensuring that farmers are main
recipients of premiums
• Capacity of programs to certify systems
according to their conservation efficiency?
– SMBC, Rainforest Alliance, SCAA all rule in
rustic coffee systems and rule out shade
monocultures. But variable for intermediate
shade intensities.
• Need to improve conservation benchmarks
(transitory habitat use to breeding viability)
• Consider yield losses; Establishing
premiums complicated due to non-linearity
of relationship between shade and yield,
and sensitivity to shade removal varies
between species
28. Shade coffee certification and conservation
• Lowest market share among fair trade,
organic, and shade-grown, 10% of all
certified exports from L. America
• Exclusively for L. American coffee
• A few certification initiatives in East Africa
(local brands, Fair Trade, Organic, Utz
Kapeh, Starbuck,….Rainforest Alliance )
• Potential of appellation coffee where shade
is a recognized practice?
29. Conclusions
• Sun coffee adapted for maximizing yields, but
optimal conditions and intensive management
are required. High environmental costs (soil
erosion, water pollution). Little knowledge of
long term effects.
• Critical role in smallholder systems with limited
management capacity in sub-optimal conditions
for moderating microclimate, diversifying
production and minimizing risk. Present by
default, but needs systematic investment.
• Lots of emphasis on Central American shade
coffee systems. Characterization, management
intensity, importance for biodiversity
conservation, commercial promotion.
30. Conclusions
• Great need to better characterize and invest in EA
coffee systems if potential of shade is to be explicitly
utilized.
• Compared to Mesoamerican regional corridor function,
conservation potential of EA shade coffee systems is
more diffused. Needs greater documentation.
• Due to high renowned quality, much potential for
developing coffee certification programs in EA
• Nascent market mechanisms to reward shade
management and coffee quality. Shade coffee best
integrated in other certification approaches
• Research on constraints in integrating trees and
commercializing products (technical, grading, prices,
knowledge)
31. Second International Symposium on Multi-Strata
Agroforestry Systems with Perennial Crops, 17-21
September 2007, Turrialba, Costa Rica, CATIE
• Biophysical interactions of shade at plant and plot level
• Quantification and valuation of environmental services
of perennial crop AFS at landscape level
• Science of certification schemes for eco-labeling of
perennial crop products from AFS
• Social and economical importance of products derived
from perennial AFS