Landscape Level Hydrological Modeling and Farm Scale Modeling in the Volta River Basin
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Transcript of Landscape Level Hydrological Modeling and Farm Scale Modeling in the Volta River Basin
Landscape level hydrological modeling
&
Farm-scale modelingFred Kizito, Katrien Descheemaeker, Sabine Douxchamps 3 / 7 / 2012
Landscape level hydrological modeling
Fred Kizito, Katrien Descheemaeker, Sabine Douxchamps 3 / 7 / 2012
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Study objectivesModeling hydrological dynamics to quantify water
fluxes for achieving optimal crop-livestock productivityo Assess sub-basin scale water balance thresholds at target
sites
o Develop water allocations framework in target sites
o Recommend best-fit integrated rainwater management strategies that maximize productivity
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Study sites
Landscape hydrological modeling:
o Conduct sub-basin water balance thresholds
o Develop a water allocations framework in target sites
o Assess water productivity in specific crop-livestock systems
Andes • Ganges • Limpopo • Mekong • Nile • Volta
• Baseline characterization has been conducted in target sites at the household level
• Tools: and
• SWAT hydrological modeling is physically based– Weather, soil properties, topography, vegetation, and land management practices data sets
• DEM:– Used at 90 m resolution– Watershed delineation; Stream network
Methods
SWAT
Andes • Ganges • Limpopo • Mekong • Nile • Volta
6
Crop water use trends in Golinga
Data Source: Ministry of Food and Agriculture, GhanaProduction estimates and Regional Crop Acreage data for 1992 to 2010 - Complemented and verified with V2 Household survey data
Andes • Ganges • Limpopo • Mekong • Nile • Volta
7
Water, crops and livestock distribution for Golinga
Source: Processed from FAO Geo-portal data-Not checked against V2 HH data
Source: Ramankutty et al, 2000Processed from Global Croplands database;Complemented with Ghana MoFA Data and V2 Household data
Andes • Ganges • Limpopo • Mekong • Nile • Volta
8
Water Balance Components for Golinga
19801982
19841986
19881990
19921994
19961998
20002002
20042006
20082010
20122014
0
200
400
600
800
1000
1200
Rainfall (mm) Surface Water Discharge (mm) Groundwater Discharge (mm)Percolation (mm) Evapotranspiration (mm)
Rain
fall
(mm
) and
Dis
char
ge (m
m)
Warm-up Calibration ValidationSim
ulated
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Milestones:Cropping density and livestock distribution ascertained for all study sites; Water balance thresholds calculated for all study sitesCurrently developing crop-livestock water productivity maps for all target sitesLandscape outputs from water allocations and water balance will complement farm-level flows analysis
ConclusionHydrological analysis indicated that reservoirs play a critical role in maintaining storage and reducing surface runoff losses at sub-basin scale
Conclusion
Farm-scale modeling
Fred Kizito, Katrien Descheemaeker, Sabine Douxchamps 3 / 7 / 2012
Andes • Ganges • Limpopo • Mekong • Nile • Volta
ObjectivesIdentify and evaluate promising interventions for improved farm productivity• Extrapolating field results in space and time• Aggregate field level outputs to farm level• Scenario analysis: exploring options• Risk analysis• Tradeoff analysis (tradeoffs in resource allocation)• Identifying issues for further (field) research• Discussion and decision support tool: informing the
innovation platform
Andes • Ganges • Limpopo • Mekong • Nile • Volta
NPKNPKNPK
Gra
in le
gum
es
Gre
en
manure
s
Agro
fore
stry
Fodder
legum
es
Manure
Fert
ilize
rs
Options
Giller et al. 2010
Andes • Ganges • Limpopo • Mekong • Nile • Volta
NUANCES-FARMSIM: farm-scale modeling approach
Tittonell et al. (2007) Fld Crops Res. 100, 348-368; Rufino et al. (2007) Livestock Sci. 112, 273-287; Chikowo et al. (2008) Ag. Syst. 97, 151-166; Tittonell et al. (2009) Ag. Syst. 101, 1-19; van Wijk et al. (2009) Ag. Syst. 102, 89-101; Tittonell et al. (2010) E. J Agron. 32, 10-21.
Andes • Ganges • Limpopo • Mekong • Nile • Volta
APSIM (Agricultural Production Systems sIMulator)
Andes • Ganges • Limpopo • Mekong • Nile • Volta
In-house feeding
Grazing
Feed gap
Constraint analysisExample of feedbase in villages around Golinga reservoir
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Baseline situation• 1.5 ha farm• household of 8 people• crops: millet, sorghum and cowpea intercropped• no crop residue stored for cattle• 3 breeding cows, sells at 4-5 years, herd of 8-10
Scenario Analysis
Adapted from McDonald (2010)
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Baseline
Animals sold (10y) 5-6
Animals on hand 12-13
Forage deficit 7000
Wet season labour +50
Cattle revenue 34000
Gross Margin* 515000
Cash balance -3000
* - including home consumption
Scenario Analysis
Adapted from McDonald (2010)
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Baseline Manure (4 t/ha)
Animals sold (10y) 5-6 6-7
Animals on hand 12-13 13
Forage deficit 7000 6000
Wet season labour +50 +20
Cattle revenue 34000 37000
Gross Margin 515000 637000
Cash balance -3000 109000
Scenario Analysis
Adapted from McDonald (2010)
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Baseline Manure (4 t/ha)
Crop residue harvesting
Animals sold (10y) 5-6 6-7 7-8
Animals on hand 12-13 13 13
Forage deficit 7000 6000 3000
Wet season labour +50 +20 +10
Cattle revenue 34000 37000 41000
Gross Margin 515000 637000 671000
Cash balance -3000 109000 140000
Scenario Analysis
Adapted from McDonald (2010)
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Baseline Manure (4 t/ha)
Crop residue harvesting
Sell cow, buy 10 sheep &
fattenCalves sold (10y) 5-6 6-7 7-8 6-7
Cattle on hand 12-13 13 13 9-10
Forage deficit 7000 6000 3000 4400
Wet season labour +50 +20 +10 +50
Livestock revenue 34000 37000 41000 96000
Gross Margin 515000 637000 671000 739000
Cash balance -3000 109000 140000 205000
Scenario Analysis
Adapted from McDonald (2010)
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Discussion support tool Learning tool
Scenario Analysis
Adapted from McDonald (2010)
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Simulation experiment
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Lessons:- Fertilizer increases average yield, but also production risk- Information on risk is useful for insurance providers (partner in the IPs?) - Water and nutrient use efficiency are interlinked
Simulation experiment
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Understanding resource allocation decisions
Resources are finite; directing them to one objective will penalize other objectives
• Labor: weeding vs. marketing produce• Cash: fertilizers vs. hiring labor for weeding • Crop residues: soil organic matter vs. livestock feeding
Tradeoff analysis
Andes • Ganges • Limpopo • Mekong • Nile • Volta
concentrates
fert
ilize
r
Tradeoff analysis
Andes • Ganges • Limpopo • Mekong • Nile • Volta
concentrates
fert
ilize
r
Tradeoff analysis
Andes • Ganges • Limpopo • Mekong • Nile • Volta
concentrates
fert
ilize
r
Tradeoff analysis
Andes • Ganges • Limpopo • Mekong • Nile • Volta
concentrates
fert
ilize
r
Tradeoff analysis
Andes • Ganges • Limpopo • Mekong • Nile • Volta
concentrates
fert
ilize
r
Tradeoff analysis
Andes • Ganges • Limpopo • Mekong • Nile • Volta
concentrates
fert
ilize
r
Lessons:- Tradeoff analysis helps us in systems understanding- Linked with understanding of socio-institutional settings (e.g. market) and farmers’
objectives, this can be used to design well-adapted interventions
Tradeoff analysis
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Farm systems models are useful tools
for research to - Understand complex farm dynamics, including farmer
decision making- Identify topics for further (field) research
for development through - Assisting in the development of adapted interventions- Generation of information for discussion support (in IPs)
! Need for high quality input data
Conclusions
Andes • Ganges • Limpopo • Mekong • Nile • Volta
Merci pour votre attention!Thanks for your attention!