Rainfed Portfolio in the Volta Basin

Land use changes in the Volta Basin

Partners:• CIAT, IWMI , CPWF

Question (on-going work):• How are the these

changes affecting livelihoods and the environment?

Way forward: • Use same approaches

in other WLE regions

Lan

d co

ver chan

ges

Cro

plan

d g

ains an

d lo

sses

Significant expansion of croplands

Losses: Diversification of farming?

Extensive Grassland

Significant forest cover

Loss of forest and cropland

Partners:• CIAT, IWMI , ICRAF, CPWF, WRI (CSIR,

Ghana)

Key outputs: • Erosion prevalence quantified • Sediment deposits in reservoirs

quantified and associated costs assessed

• Vulnerable spots identified for targeted interventions with implementing partners

Potential Impact:• Long-term restoration of soils that

improves system productivity

Way forward: • Use similar approaches in other

WLE regions

Ero

sion

prevalen

ceS

edim

ent lo

sses

Soil erosion (%)

100

0

Soil erosion and Sediment deposits

Computed using InVESTto identify vulnerable areas in basin with high sediment losses

Derived with field data from AfSIS:Vågen, et al 2013

Water and Sediment fluxes in White Volta Basin

Partners:• CIAT, IWMI , CPWF, Water Resources

Commission (WRC), Water Research Institute (WRI, CSIR) and Ministry of Food and Agriculture (MoFA)

Key outputs: • Estimate of sediment yields permits

relevant mitigation measures and recommendation e.g. grass strips buffers along waterways

Way forward: • On-going stakeholder engagement

towards Integrated Water Resources Mgt.

0

0.1

0.2

0.3

0.4

0.5

0.6

1996 1997 1998 1999 2000 2001 2002

Annu

al T

otal

Sed

imen

t Yie

ld (T

/H)

Validation Years

Simulated

Measured

Study area is Zebilla in Upper East Region of Ghana; water yields and sediment estimates reveal impacts of these variables on crop productivity in the landscape

0

500

1000

1500

2000

2500

3000

3500

4000

4500

1971 1976 1981 1986 1991 1996 2001

Annu

al V

olum

e of

wat

er (M

m3)

Zebila water yield Total water yield

The InVEST FrameworkIntegrated Valuation of Ecosystem Services and Tradeoffs

Stakeholder process

Real land use representation

Mutual optimal land use

En

tire

Bas

in

Res

. su

b-b

asin

s

AR

S

Res

. Su

b

Location

0

1

2

3

4

5

6

7

8

9

10

Sed

imen

tati

on

co

st (

mill

ion

s $

)

7.4

6.8

2.7

4.1

Outcome:• Inclusive and

informed dialogue process on landscape resources management

Way forward: • Mimic similar

approach in other WLE regions

Partners:• IWMI, CIAT,

Bioversity, CPWF

The InVEST framework uses relevant critical pieces for more holistic natural resources management

En

tire

Ba

sin

Res

. su

b-b

asi

ns

AR

S

Res

. Su

b

Location

0

100

200

300

400

500

600

Se

dim

enta

tio

n (

ton

s)

592

546

218

328

Social processes in landscapes

Wet season Dry season

Outcome:• Participatory engagement at various

levels of society• Gendered landscapes: Entry point for

equity in landscapes• Tease out seasonal components Way forward: • Use same approaches in other WLE

regions

Various stakeholders (at various levels in society) represent the landscape through dialogue on how resources are used over a given time and space

Partners:CIAT, IWMI,

CPWF, CIRAD, WRC

Ecosystem Services Assessment

Ecosystem Impacts0

20

40

60

80

100

% R

esp

on

den

ts

Ecosystem Impacts0

20

40

60

80

100%

Res

po

nd

ents

Ecosystem Impacts0

20

40

60

80

100

% R

esp

on

den

ts

Ecosystem Impacts0

20

40

60

80

100

% R

esp

on

den

tsLawra Tolon

Bawku W est Cohorts average

Bush burningPesticides application for fishingErosion/sedimentationRiver bank cultivation

Partners:• CIAT, IWMI , Bioversity, CPWF

Key outputs: • ESS characterized• Trends assessed

Way forward: • Assess impact of habitat

conversion on ESS trends• Quantify ESS trends• Use same approaches in other

WLE regions

Assessments reveal key priority issues over time and space that deserve interventions and mitigation measures to sustain viable ecosystem services and prevent human health risks

Ecosystem Services and Trends in two Volta Basin transects

Partners:• IWMI, CIAT, Bioversity, CPWF

Key outputs: • ESS characterized• Trends assessedWay forward: • Assess impact of habitat

conversion on ESS trends• Quantify ESS trends• Use same approaches in other

WLE regions

Rainfall less than 900 mmyr-1

Greater than 900 mmyr-1

Radar chart revealsincreasing importance of flood control and erosion with reduced water quality soil fertility trends

Radar chart revealsincreasing importance of sedimentation,flood control and erosion with reduced biodiversity trends

On-farm testing of mitigation recommendations

Partners:• CIAT, IWMI, CPWF, IITA, USAID, WRI , ARI, KNUSTKey outputs: • Farmer participatory monitoring of rainfall events• Rain water harvesting, farmers’ use of soil and

water conservation technologies• Real time monitoring of soil moisture for seasonal

changesImpact• Increased crop yields in on-farm trials• Farmer training in soil and water management Way forward: • Identify intensification pathways that impart

system resilience for increasing land and water productivity

• Investigate the impact of labor intensive practices on system productivity

Soil moisture storage, crop water productivity and gross value of production were consistentlyhigher in treatments with fertilizer micro-dose+20 kg manure and tied ridging, what about labor?

Legend: Inputs effect on soil moisture

Achieving impact-oriented research

Reliable rainfall

Viable Ecosystems

Enabling conditions

Adequate water resources,

viable ecosystems & healthy soils

- Rainfall variability impacts farming- Need for risk reduction through:

o Sustainable land and water mgto Increased landscape biodiversity

- Consider a holistic landscape framework- Equitable participatory engagement- Conduct tradeoff analysis

- Strategic and targeted partnerships- Appropriate policies and- Proper Institutional arrangements

From good soils, ecosystems and water resources to entry points for food security, improved livelihoods and viable landscapes