The average rate of soil loss in Zimbabwean communal areas is estimated to be 50tonnes/ha/year. The immediate challenge facing Zimbabwe is to devise soil protectiontechnology to minimize soil loss and achieve sustainable agriculture. From the research donein Zimbabwe conservation tillage methods such as tie-ridging, mulching and use of Vetiveriazizaniodes are useful and cheap methods of reducing soil erosion.Ridging involves shaping the surface of the land into continuous 'strings' of smallbasins. Rain water is retained in the basins so that it can soak into the soil between stormsresulting in very little runoff. This method is cheap and is particularly applicable to communalfarming.Mulch farming involves the slashing of crop residues into small pieces that are lefton the soil surface as a protective cover. The mulch protects the soil from the impact of theraindrop thus allowing a high infiltration rate to be maintained.The mulch also shades the soil and therefore helps in moisture conservation. Onsmall-scale farms with well-drained soil, usually 22 tons/acre/year of soil is lost due to erosion(Stocking, 1986). However when tie ridging is used only 0.9 tons/acre of soil is lost. Forheavy soils in commercial farming areas only 2 tons/acre of soil is lost per year when tieridging is used. When trash or mulch is applied to a heavy soil, the soil loss was even muchlower at 0.4 tons/acre/year.Vetiver is used as an erosion control method in Zimbabwe. In the Eastern Highlandsa number of coffee planters use it to protect their terraces. Vetiver has also been plantedacross wet drainage flats (vleis) where it blocks the runoff and keeps the soil moist formonths into the dry season. Vetiver has the advantage that it does not require expensiveinputs or equipment for its establishment. It does not need laborious maintenance and mostof all it is acceptable to most users and thus involves the local people themselves in erosioncontrol activities.All the soil conservation technologies developed will not be of use unless a good soilerosion control education system is set up to make people aware of ways they can contribute
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