An empirical model for estimating soil wetting pattern dimensions during film hole irrigation. Issue 13 (9th November 2020)

• Record Type: Journal Article
• Authors: Fan, Yanwei; Shao, Xiaoxia; Gong, Jiaguo; Wang, Ying
• Is Part Of: Archives of agronomy and soil science. Volume 66:Issue 13(2020)
• Page Start: 1765
• Page End: 1779
• Publication Date: 2020-11-09
• Subjects: Film hole irrigation -- wetted radius -- wetted depth -- empirical model; Horticulture -- Periodicals; Soils -- Periodicals; 630.5
• DOI: 10.1080/03650340.2019.1694147
• Languages: English
• ISSNs: 0365-0340

Abstract

ABSTRACT: Studying the dimensions of soil wetting pattern (SWP) is important for designing optimal film hole irrigation (FHI) systems. HYDRUS-2D was used to simulate the dynamic changes of SWP under different soil texture (ST), initial moisture content ( θ i ), film hole diameter ( D ) and irrigation water head ( H ) during FHI. The results indicate that ST and D, rather than H and θ i, have a significant impact on SWP. Based on the simulation results, a power function was utilized to fit the horizontal radius ( X ) and vertical depth ( Y ) of SWP. The relationship between the fitting parameters and D, H, and saturated hydraulic conductivity ( K s ) was analysed. An empirical model for estimating the X and Y was produced. Data from laboratory experiments and published studies were adopted to assess the empirical model. The results showed that the X and Y calculated using the empirical model were highly consistent with the observed data. The values of root-mean-square error vary from 0.355 to 1.107 cm and Nash Sutcliffe efficiency is closed to 1.0. In this study, the only parameter required for the empirical model is K s, which can provide valuable and practical tools for FHI design.