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Segregate or integrate for multifunctionality and
sustainagility
Symposium at 2nd World Congress of Agroforestry
26 August 2009, Nairobi
Sustainable livelihoods somewhere on the globe
Sustainable livelihoods at current location
Sustainable farmsat current location
Sustainability of currentfarming system
Sustainability of current trees/crops/animals
Sustainability of current cropping system
Sustainagility E:human migration
Sustainagility D:shift to non-ag
sectors
Sustainagility C:other farming
system
Sustainagility B:other cropping
system
Sustainagility A:other trees/crops/
animals
• Supporting the ability of farmers to remain agile in responding to new challenges, by adapting their production system
• Resilience or adaptive capacity are properties of the actors, sustainagility that of the system in which they function
• Resilience may indicate return to status quo, agility refers to continuously moving targets
• Sustainagility + Sustainability => Probability of meeting future needs
Sustainagility
segregate
integrate
Minimize length of sharply defi-ned boundaries
Gradients, maxi-mize interactions
Two basic ways to achieve ‘multifunctionality’
Zones – land use plans: rules &
rewards
Local Livelihoods & Local& Global Biodiversity
intensive agriculture
natural forest
integrated, multifunctional
landscape: crops, trees, meadows and forest
patches
Tree plan- tations
intensive
extensive
conservation
protection
production
Agr
ofor
estr
y
Agr
icu
ltu
re
F
ores
try
Segregate Integrate functions
Current legal, institutional & educational paradigm
Current reality
‘deforestation’
‘loss of forest functions’
Integrate Segregate
Tree cover:
Deforestation, Reforestation
Less patchy:
Inte-grate
More patchy: Segre-gate
More trees
ag
rofo
rest
atio
n
re- and afforestation Less trees
defore
stat
ion
forest m
odification
Fields,fallow, forest mosaic
Farm fo-restry, agrofo-rests
100% forest
Fields, Forests & Parks
Open field agriculture
Less patchy:
Integrate
More patchy:
segregate
Fewer trees
More trees
Food bowlFields and fallow
Protected forests, parks, cities and fields
Agroforests, Farm forestry
Ecosystem quality
Biodiversity
Environmental services
High
Low
Low High
Agricultural productivity: goods
impossible
A. Agroforest landscapes
D. Intensive agriculture landscapes
B. Fragile agro-ecosystems
C. Biodiversity friendly agricul-ture?
Pathways to be avoided Socially desirable pathway
‘Natural’ point of reference
‘Potential production’ as reference
Ecosystem quality
Biodiversity
Environmental services
High
Low
Low High
Agricultural productivity: goods
impossible
A. Agroforest landscapes
D. Intensive agriculture landscapes
B. Fragile agro-ecosystems
C. Biodiversity friendly agricul-ture?
Pathways to be avoided Socially desirable pathwayPathways to be avoided Socially desirable pathway
‘Natural’ point of reference
‘Potential production’ as reference
We compare a system (fx, Ix) with a system (fy, Iy) such that fx Yx = fy Yy, or fx (Ix)p = fy (Iy)p
Comparison is made on the basis of 'biodiversity deficit' in comparison to a completely natural landscape:
Def_x: (Bn - Bx)/ Bn =1-((1-fx) + fx Br/Bn + fx (1-Br/Bn) (1-Ix)q) = fx (1-Br/Bn) (1-(1-Ix) q)
Def_y: (Bn – By)/ Bn =1-((1-fy) + fy Br/Bn + fy (1-Br/Bn) (1-Iy)q) = fy (1-Br/Bn) (1-(1-Iy) q)
RelBiodivChange = (Def_y - Def_x)/Def_x = 1 - (Ix/Iy)p * (1-(1-Iy)q) / (1-(1-Ix)q)
Start at I = 0.2
-0.4
-0.2
0
0.2
0.4
0.6
0 1 2 3
q
Rel
Bio
div
Ch
ang
e
Start at I = 0.5
-0.4
-0.2
0
0.2
0.4
0.6
0 1 2 3
q
Rel
Bio
div
Ch
ang
e
0.3 0.5
0.7 0.85
1 1.15
1.3 1.45RelBiodivChange indicator as a function of p and q for two starting points of intensification, both with a stepwise increase in I of 0.3
Yield response for various p values
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 0.2 0.4 0.6 0.8 1
Intensity of land use
Yie
ld
0.3
0.5
0.7
0.85
1
1.15
1.3
1.45
Biodiversity response for various q values
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 0.2 0.4 0.6 0.8 1
Intensity of land useB
iodi
vers
ity
0.20.511.121.67234
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 0.2 0.4 0.6 0.8 1Intensity
Bio
div
ersi
ty d
efic
it,
f(ag
) .
fx, Ytot= 0.3RAF, Ytot= 0.3Food crops,Ytot= 0.3fx, Ytot= 0.5RAF, Ytot= 0.5Food crops, Ytot= 0.5
The biodiversity deficit increases
with intensification in case of rubber
agroforestry
The biodiversity deficit decreases with intensification
in case of food crops…
The appreciation by local and ex-ternal stakeholders of the envi-ronmental services that remain-ing forest + agroforest patches provide tends to depend on how much forest is left, as well as the spatial pattern.
Hypothesis on landscape patterns
In forest-rich landscapes, forest functions are taken for granted at the local scale, even if they represent considerable value from a global perspective; in landscapes with little forest left, the environmental services of the remaining forest may be highly valued locally, but probably represent little of interest to global stakeholders (as sensitive species will most likely have disappeared).
Following this logic, it is in interme-diate landscape mosaics that forms of ‘environmental service rewards’ will be needed, as external value exceeds local appreciation, while (supposing that loss of forest cover continues) conservation may in fact match future local appreciation.
Real-world land use systems
Unknown territory
Net present value based on product flows, $/ha
Plot-level Carbon stock, Mg/ha
Total economic value, k$
Landscape-level Carbon stock, Tg
1A
1B
2A 2B
Open-field agriculture
Agroforests
Intensive tree crops
0
0.2
0.4
0.6
0.8
1
0 0.2 0.4 0.6 0.8 1Land use intensity
Re
lati
ve
fu
nc
tio
na
lity
RAFREFPriv.Cost
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0 0.2 0.4 0.6 0.8 1Land use intensityR
ela
tiv
e f
un
cti
on
alit
y
Private Benefit A
Private Benefit B
Private Benefit C
CB
A
-0.2
-0.10
0.10.2
0.3
0.40.5
0.60.7
0.8
0 0.2 0.4 0.6 0.8 1
Land use intensity
Ma
rg. b
en
efi
t in
ten
sif
ic.
Scenario_A
Scenario_B
Scenario_CCB
A
Relationship between land use intensity, agronomic functionality (linked to yield), costs and net benefits, for three scenarios that reflect increasing relative ‘weight’ of the environmental services in the net benefit function:
0,02, 0,1 and 0,2 for scenarios A, B and C, respectively