Prediction of Size and Shape of Wetting Patterns Created by Inverted Open Plastic Bottles (IOPB)

Plastic bottles can be used in irrigation fields which introduces a sustainable low-cost alternative for irrigation methods. Until now, plastic bottles were used in small irrigation fields since there are limited scientific measurements of it is performance. The aim of this study is to predict the size and shape of the wetting patterns generated by inverted opened plastic bottles. Hydraulic simulations for 48 design cases of 12 different soil types and 4 sizes of subsurface source were accomplished using 2D-Hydrus. The simulation outputs were validated using experimental results. Multi regression analysis was used to identify the general formulae of the dependent variables of hydraulic conductivity, area of subsurface source, depth of the source, head of application, and time of application. The statistical analysis was formulated by the R-studio program. Results show that the maximum width and depth of wetting patterns occurred in sandy soil which were 34.1 and 96.8 cm, respectively. The minimum values were in silty clay with the width and depth of wetting patterns of 4.3 and 19 cm, respectively. The standard deviation of the width and depth were 9.02 and 22.58, respectively.  In conclusion, the soil type is a vital factor that impacts the flow in the soil profile and the size and shape of the wetting patterns. In addition, the size and depth of the subsurface source impact the size and location of the wetting patterns. The Head of the water in IOPB can be used to specify the size of the wetting patterns. The statistical model can be used to predict the size of the wetting patterns created by IOPBs accurately.