TY - JOUR
T1 - Evaluation of Field Performance of Steady State Drainage Equations for Sugarcane Agro-Industrial Company in Khuzestan
TT - ارزیابی صحرایی عملکرد معادلات جریان همگام زهکشی در کشت و صنعت نیشکر خوزستان
JF - JSTNAR
JO - JSTNAR
VL - 23
IS - 3
UR - http://jstnar.iut.ac.ir/article-1-3291-en.html
Y1 - 2019
SP - 157
EP - 168
KW - Design of subsurface drainage system
KW - Conventional drainage equations
KW - New drain spacing formulas
KW - Steady state flow
KW - Ground water table
N2 - Selection of drainage equation with acceptable accuracy has always been a challenge for designers to design subsurface drainage systems. In this research, seven steady state drainage equations were used for predicting daily and cumulative drainage rate on a farmland of sugarcane in Imam agro-industrial Company. These drainage equation included Hooghoudt, Ernst, Kirkham and Dagan that have been developed in the past and Mishra and Singh, Henine and Yousfi et al that recently developed. The statistical indices consist of P-value, RMSE, R2 and Percentage Error of estimating cumulative drainage rate were calculated for Hooghoudt equation 0.9501, 1.49 (mm/day), 0.80 and -0.19%, respectively. For Ernst equation 0.0001, 2.46 (mm/day), 0.34 and 16.98%, respectively. The result of performance of drainage equations revealed that Hooghoudt and Ernst equation were as the equations with the highest and lowest accuracy in predicting drainage rate, respectively. Also from the newly developed equations, the Yousfi et al equation was found with relatively well accuracy to predict the drainage rate. This equation was placed in second rank after Hooghoudt equation and other equations showed poor performance. Thus, with selection of the appropriate drainage rate, the Hooghoudt equation is suggested for designing of drain spacing in medium to heavy textured soils such as sugarcane agro-industrial.
M3
ER -