Mapping rainwater management strategies at landscape scale Nile 3 on targeting and scaling out

Mapping rainwater management strategies at landscape scale

Nile 3 on targeting and scaling out

Overview

• Introduction

• Concepts used (definitions)

• Modeling framework with illustration

• Using the maps

• Up-coming research 2

Targeting and scaling out tool

Objective

•Feasibility maps that includes bio-physical and socio-economic criteria

•Landscape approach to rainwater management modeling

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intro concept framework use up-coming

Overview

• Introduction



• Using the maps


Some definitions

• Rainwater management practice = farmers’ choice to improve water retention or water productivity

• Soil and water conservation (bunds, …)• Water harvesting • Tree (agro-forestry)• Livestock and grassland management• Crops and fertility management

• Intervention = “external actor” to enable a practice change

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Landscape approach to water


Highland : infiltration ↑

Midlands : SWC ↑

Lowlands : efficiency ↑

Landscape approach to water


Rainwater management strategy

Zone Cropland Grassland DegradedUplands Increase infiltration

Orchards, multi-purpose trees

Increase the quantity and quality fodder for livestockGrassland management

Rehabilitated degraded landGully rehabilitation

Midlands Increase SWCTerraces, bunds

Lowlands More efficient use waterRiver diversion, wells

Independent Increase water in dry seasonWater harvesting

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Overview

• Introduction



• Using the maps


Modeling framework

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Mapping RMS at landscape scale

Rainwater management strategy map

Feasibility map

practice B

Feasibility map

practice C

Transformation into spatially explicit variables and threshold definitions

Identification of bio-physical conditions, socio-economic and institutional drivers for each individual practice

(diversion, terraces, trees,…)

Feasibility map

practice A


Modeling framework

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Feasibility map

practice B

Feasibility map

practice C




Feasibility map

practice A


Database of 80 practices

Modeling framework

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Feasibility map

practice B

Feasibility map

practice C




Feasibility map

practice A


Suitability criteria

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Modeling framework

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Feasibility map

practice B

Feasibility map

practice C




Feasibility map

practice A


Getting single feasibilty mapsBio-physical suitability Willingness to adopt

Feasibility map


Biophysical suitability maps

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equal weight aggregation

Apple tree Minimum temperature below 10cLuvisol, nitisol, leptosolRainfall >1400 mm


Adoption maps : Small area estimation technique

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Adoption rule for orchard

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Variable at farm level Orchards Variable at woreda level

household density 0.0184(0.029)

Population density

Landholding 0.2062(0.001)

Average landholding

Average plot size -1.7489(0.000)

Average plot size

Red soil 0.4232(0.020)

Nitisol

Access to advise 0.2378(0.050)

Percent of HH with access to advise

Access to credit -0.2450(0.038)

Percent of farmers with access to credit

Constant -1.1780(0.000)

Constant

Pseudo R-squared 0.07

Adoption rule for SWC

Variable at farm level Soil and water conservation

Variable at woreda level

Landholding -0.3772(0.000)

Average landholding

Landholding squared 0.0324(0.020)

Clay soil -0.3268(0.027)

Vertisols

Access to advise 0.4188(0.000)

Percent of HH with access to advise

Off farm activity 0.2843(0.011)

Agricultural dependency

Hired labor 0.5060(0.000)

percent of HH with hired labor

Constant 0.61510.004

Constant

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Adoption rule for diversionVariable at farm level River diversion Variable at woreda

level household density 0.0092

(0.020)Population density

Landholding 1.2426(0.000)

Average landholding

Landholding squared -0.1488(0.000)

Average plot size -3.6047(0.001)

Average plot size

Hired labor 0.8920(0.000)

percent of HH with hired labor

Time to output market 0.9975(0.005)

Time to market

Time to output market squared

-0.1962(0.043)

Constant -3.2910(0.000)

Constant

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Willingness of adoption maps

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Feasibility maps

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Modeling framework

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Feasibilty map

practice B

Feasibilty map

practice C




Feasibilty map

practice A


Strategy quantification

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Objective Example quantification

1 Identify landscapes in which sufficient area are suitable in bio-physical terms.

At least 10% of the area is suitable for SWC and terracing and at least 2% of the area is suitable for river diversion

2 Identify landscapes where people are likely to adopt the strategy

The minimum adoption on suitable area of any of the three practices is bigger than 0

3 Identify landscape where sufficient area is feasible both in bio-physical and socio-economic terms.

Combination of the conditions of quantification 1 and quantification 2

Aggregation into strategies at landscape scale

zonal overlay with a landscape layer

Bio-physical map, willingness of adoption map, feasibility map

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Overview

• Introduction



• Using the maps


Using the maps

• High uncertainty

• Difficulty to validate the maps

• Entry point to start a discussion with community

• Towards an open source GIS tool for policy makers, research centers, NGO, extension service

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Overview

• Introduction



• Using the maps


Up-coming research

• Map validation in 4 new watersheds • Using the “happy strategy game”• Farm household survey (600 farmers)

• Impact assessment • on hydrology, ecosystem services, livelihoods

• Explorative scenarios

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Practice Biophysical criteria Expected socio-economic and institutional criteria

Apple tree Minimum temperature below 15cLuvisol, nitisol, leptosolRainfall >1400 mm Crop land

Distance to market Land holding size

Mango trees NitisolRainfall > 1400 mmCrop land

Distance to market Land holding size

Multipurpose treeSesbania sesban

Rainfall 500-2000 Crop land, medium and high degradation

Age, Household sizeLand holding sizeRented landLand fragmentationLivestock intensity

Bench terracing Rainfall < 1400mmsoils drainage ≠ poorSlope between 12-58%Crop land

Household sizeHired laborAccess to advice Land fragmentation Agricultural dependencyRented land

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Hillside terracing Rainfall < 900mmslope 10- 50%Crop land

household sizeLand holding size Hired labor Access to advice Land fragmentationAgricultural dependencyRented land

Soil bund rainfall < 1400 mm slope 3-15% on rainfall > 1400mm if graded soil ≠ leptosol soil drainage ≠ poor≠ degraded land


Stone bund slope 5-35%rainfall < 1400 mm and rainfall >1400 if soil = nitisol and if drainage = good (MoRAD) ORsoil type = leptsolsoil texture = medium


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Fanya-juu rainfall > 900mm rainfall <900mm if elevation >1500 slope 3-15%soil = nitisol

Agricultural dependencyLivestock intensityAccess to creditAccess to extension service Landholding per personEducationHousehold size

River diversion 2.5km around perennial riversoil texture = fine

Access to capitalHousehold sizeAccess to adviseAccess to market

Well very shallow + shallow aquifersslope < 35% soil ≠ leptosolNormalized topographic index between 0.8-1

Access to marketAccess to credit Household sizeLandholding size

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Gullies Normalized topographic index between 0.8-1

Informal institution map?

Area exclosure Grassland Informal institution map?

Water harvesting No forest Access to marketAccess to credit Household sizeLandholding size

Documents

Mapping rainwater management strategies at landscape scale Nile 3 on targeting and scaling out