Gowing, J.WYoung, M.D.BRwehumbiza, B.R.2017-12-182017-12-1819990856 668Xhttps://www.suaire.sua.ac.tz/handle/123456789/1930Tanzania Journal of Agricultural Sciences 1999, Vol. 2(2) ;pp 227-238Experimental research into suil-water management, whether un a research statiun or on fanners' fields, is necessarily restricted to ,spec'ijic sites over limited time illtervals. Meaningful extrapolation is a problem. With this in mind,.·the SUA-Newcastle RWH project pursued a twin-track approach in which the experimental. effOlt .. was lillked.to the development of a simulatioll model, which was designed to assess the suitability of RWH technology intervelltions for allY Ilew site. The simulation model is briefly described (lIzd typical examples of its use as a toul for agrotechnology transfer are presented. The interface is user-friendly alld the n;.odel itself is designed to work with readily available site data. Long-term simulation at a new site C(llZ be easily achieved to permit evaluation of averagepeljOl:mance and/or variability and risk. The yield-gap ullder existing practice can be evaluated alungside predicted peljormance under improved practice. Examples of the application of the model are givell for a maize cropping system and for a rain-fed rice cropping system in two different regions of Tanz(llzia.enSimulationRWHSemi-aridTanzaniaArticle