Research Thrust

To build evidence that improving water management through the IWRM paradigm improves rural livelihoods at the scale of the water management intervention:

Field scale – farmersLocal catchment scale – communities, villagesSub-basin scale – districts, provincesBasin scale – transboundary

Research Areas

Improved understanding of water resources

Farmer field-based action research (agriculture)

Institutional Research

Water Resources Research

Rainfall and Runoff Variability

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Filabusi Mbalabala

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Kezi Beitbridge

(b)

Rainfall-Runoff Modeling

Good simulation of runoff within catchmentsSWAT (Soil Water Assessment Tool) model

application in Olifants Reduction in streamflow with inc. land cover

HBVx Model in MzingwaneInterception an important process (56% in a

dry season 2006/07, 32 % of rainfall in normal season 2007/08)

Stream flow driven by rapidly draining shallow groundwater

Rainfall and runoff analyses (Pettitt Test) - change to drier regime since 1980

Runoff Generation Modelling

Hydrogeological StudiesSmall sand rivers

Limitations Evaporation (< 100 km2 give few months supply) Geology (seepage a stronger control than evap.)

Large systems (Lower Mzingwane) –WAFLEX ModelAlluvial aquifer can store up to 38million m3 of

waterAdditional 3600 ha of smallholder farms can be

potentially irrigated with the water

Lower MzingwaneCurrent Max. smallholder irrigation

from alluvial aquifers

Water QualityChallenges, esp. metal pollutionMozambique:

Major problems with metals: Zn, Cu, Pb, CdDesign of a monitoring network done

ZimbabweGold panning - potential Hg pollution in riversNatural salinity in shallow groundwater

Cadmium riskThese studies and one from SA point to

dangerous levels of Cd

Agricultural Research

Conservation Farming

Zimbabweplanting basins, ripping, conventional spring

and double ploughingBasin tillage showed lowest runoffReduced runoff did not translate to highest

yield under these conditionsModeling indicates that basins perform better

MozambiqueBasin tillage showed significant yield increase

compared to conventional tillage

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Crop Water ProductivityCrop simulation modeling in SA and field

studies in ZimbabweIncreasing fertility (N) increases water

productivityCrop water productivity (returns/mm)Use of the APSIM Model in simulating grain

yield and crop water useAPSIM performed well

Rainwater HarvestingMozambique

Inventory showed 21% adoption of pits compared to flood recession, small dams and road runoff

ZimbabweEvaluation of rainwater harvesting technologies in

the Mzingwane CatchmentDead level contours perceived as most effective by

farmers, but measurements??Soil type and resource status were important factors

South AfricaChololo pits increased maize grain yield compared

to conventional farming

Supplemental IrrigationRain fed vs supplemental irrigation in South

AfricaDrought year moisture deficit during

flowering stage was reduced Supplementary irrigation raised yield from

0.6 to 2.0 t/ha

Soil Salinity Studies- ChokweSalinity management

strategies in irrigationSalinity reduces yield

and hydrological processes play a role – potential to model the system??

Scenario analysis to improve irrigation performance and efficiency

Institutional Research

Models of Catchment Planning

Mzingwane Catchment CouncilChanges in the structure of the modelUnderstanding the role of women Outline plan, addressing weaknesses that were

identified by PhD researchWater chemistry results being taken seriously

BUT, confusing messages on CA, dead level contours

MCC appreciates the work of Phase PN17 so far

Evaluating Stakeholder Participation

Water User level -Lowest to district/sub-catchmentWater access

Private, communal, generally poor access at user level

Institutional processes‘New’ institutions are a manifestation of negotiation

processes by usersOutside intervention dictates the processes

Rights creationAppropriative rights the most common form of

creationCommunal rights do not mean much without a

legitimate and acceptable enforcer

Institutional Mapping and Performance

Water resource management at the local level – MzingwaneIdentifying practices, linkages and weaknessesCA and donor influenceWater resource planning

The importance of the culture based normative framework in water resources management

Approaches to planning for water resource – bottom up approach more relevant

MainstreamingCapacity Building (CB)

Outreach through capacity building in the communities and institutions

CB was not follow-up or not a later add-on to research

CB is mainstreamed: Integrated into project from planning stage

onwardsInvolving all scientistsInvolving farmers and management agencies

Capacity Building & Knowledge Outputs32 MSc students completed 2 in progress 8 females, 25 NARES staffPhD students:

One student has graduated3 more students likely to complete by Dec 2009

5 farmer groups supportedPublications: 24 articles, 12 chapters, 81 conf.

papersWorkshops: 5 basin level, 8 catchment level

workshops

Decision-Support: Integrative ModellingCoupling models into a decision support tool -

ICHSEA ArcView 3.3 interfaceSWAT output to PARCHED-THIRST, its

output to OLYMPEUncertainty analysis in progressScenarios: full-scale additional irrigation,

supplementary irrigation, different water sources

Strategic tool, not an operational tool

ConstraintsRainfall variability and droughtStaff turnover and brain drainPolitico-economic conditions in ZimbabweBudget constraints

Thank you!!!