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UKAID Department for International Development (R4D) 1999

Weed management options for seasonally inundated land in semi-arid Zimbabwe - revised

Weed Management Zimbabwe

UKAID Department for International Development (R4D)

Titre : Weed management options for seasonally inundated land in semi-arid Zimbabwe - revised

Pays : Zimbabwe

Projet de recherche pour le Développement : R7473

DFID Programme : Crop Protection

Organismes de mise en œuvre
Lead Institutes : Silsoe Research Institute
Managing Institutes : Natural Resources International Limited (NRIL)
Collaborating Institutes : AGRITEX Institute of Agricultural Engineering ; AGRITEX Soil and Water Conservation Branch, Makoholi Experimental Station ; Department of Crop Science, University of Zimbabwe ; Department of Soil Science and Agricultural Engineering, Faculty of Agriculture, University of Zimbabwe ; Institute of Environmental Studies, University of Zimbabwe (IES) ; Rothamsted Research

Durée : 01-10-1999 à 30-12-2002

Présentation
Low cost, labour efficient weed management systems which conserve moisture in savannah cropping systems developed and promoted.
Vleis are recognised by rural Zimbabweans as a potentially valuable resource that play an important role in the stabilisation of rural household economies, and make a major contribution to food security during times of drought. Although vleis are widely cultivated, current legislation in Zimbabwe attempts to conserve vleis by restricting their use, which has meant that little work has been carried out to understand and alleviate the production problems faced by farmers, to ensure that the vleis are used in a sustainable manner. The major problem facing smallholder farmers in this ecology is weed control and soil water management, particularly in wet years, that can lead to fields being abandoned and resources directed to drier topland soils. However, maize yields in excess of 7t/ha have been achieved on commercial farms in both wet and dry years when fertility issues, water management and weed control have been properly addressed. Much of the erosion that has led to the current legislation (1927, Water Act ; 1941, Natural Resources Act ; 1952, Streambank Protection Regulation) has been attributed to inappropriate agrarian reforms, and growing population pressures in communal land areas. Studies of sequential air photographs have revealed a strong relationship between variations of rainfall and livestock numbers, rather than cultivation, since the 1950s. This is in contradiction to conventional wisdom. Of the 240,000 ha of vleis found in Zimbabwe’s communal lands, there is maximum potential for some 80,000 ha of cultiviable vlei. A safe limit on the extent of vlei cultivation is considered to be 10% of the catchment area or 30% of the vlei, whichever is the smaller. Therefore, alleviating the weeding constraint in these vlei areas will contribute to more stable yields, reduce the pressures for cropping on the drier, more fragile topland areas of the soil catena, and contribute to enhanced food security, and alleviate poverty, particularly for poorer households.

Total Cost to DFID : £226,362

Présentation : UKAID

Page publiée le 19 octobre 2015, mise à jour le 28 octobre 2017