Dryland farming tillage and water-harvesting guidelines for the Yemen Arab Republic

Abstract

Mouldboard ploughing to 400–500-mm depth constitutes the standard primary cultivation practice on the medium textured soils used for dryland crops in the semi-arid, inter-montane plains of the Yemen Arab Republic. The justification for this practice is examined and guidelines for the future development of tillage and water-harvesting practices are identified, based on the physical characteristics of the different soil horizons. Major benefits, in terms of increased and more reliable crop production, could accrue through increased water availability from developing flexible water-harvesting systems and through bringing more structurally stable sub-surface soil horizons onto the surface. The development of controlled-traffic systems within the water-harvesting systems would greatly assist in reducing tillage costs. The identification of a satisfactory alternative method to the mouldboard plough for perennial rhizomatous weed control would help maintain the improved soil surface condition.