Modelling Soil Water Dynamics under Trickle Emitters - a Review

Information on moisture distribution patterns under point-source trickle emitters is a pre-requisite for the design and operation of trickle-irrigation systems. The distribution pattern is influenced by the soil properties and the manner water is applied and withdrawn from the soil profile. Flow from a point-source trickle emitter, because of its multi-dimensional nature and high frequency of water application, leads to complexities in modelling soil moisture dynamics. In addition, the plant rooting patterns under such conditions also exhibit drastic variations in withdrawal patterns from those in conventional irrigation practice, thereby making the prediction of the behaviour of moisture patterns quite difficult. An extensive review is presented of research work pertaining to modelling of various processes associated with moisture distribution patterns under point-source trickle emitters. This review promotes better understanding, facilitates a more rational analysis of the soil water dynamics processes under point-source trickle emitters and helps to identify topics for more emphasis in future modelling activity.