The Effect of Heterogeneity Due to Inappropriate Tillage on Water Advance and Recession in Furrow Irrigation

Abstract

In surface irrigation, uniformity of longitudinal slope and depth of tillage are very important factors in advance duration time. Inappropriate tillage and land preparation can cause uneven surfaces and non-uniform slopes in fields which is especially important in furrow irrigation due to their influence on advance times. The purpose of this study is to evaluate the effect of non-uniform longitudinal slope due to inappropriate tillage on advance and recession phases in furrow irrigation system, which plays an important role in irrigation uniformity and application efficiency. For this purpose 12 furrows, each 42 m long were made with different longitudinal slopes and a width of 0.6 meter. The number of irrigation was 5 with irrigation interval of 4 days and input discharge of 0.8 lps. Results showed that advance times are very different in furrows especially in the first irrigation and varied from 19min up to 50min. The values for recession time were 9 to 29 min. The results of these five irrigation events indicate that non-uniform slope has significant effect on advance and recession time. Therefore with attention to the water crisis and the need to increase efficiency and uniformity of water distribution in surface irrigation, using modern machinery and paying more attention to accurate preparation of land are necessary in order to obtain uniform furrows in fields.

A Simple Method for Land Grading Computations and its Comparison with Genetic Algorithm (GA) Method

“…GA will be working with a group of most-fit decision vectors. In contrast, the more traditional nonlinear and linear optimization procedures work with only one decision vector at any given time [34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49]. GA uses a wide variety of parameters as decision variables.…”

A Proper Way to Install Trapezoidal Flumes for Measurements in Furrow Irrigation Systems

“…The discharge measurement of h1under free flow conditions at the flume's entrance should be read. If the ratio of submergence is 80% or more then the correction factor shown in Figure 1 should be used [16][17][18]. It should be noted that the primary equation for the flow in the flumes results from the energy equation and continuity equation [19].In the present research a proper way to install trapezoidal flumes applicable under non-submerged conditions in the furrow irrigation systems is investigated.…”

Flow Hydraulic Investigation of the Wastewater on the Soil and Magnetic Field Effects in This Field

“…To apply the actual conditions in the field, two lateral furrows were considered for each main ones and tests were done in the main furrow. 60 furrow irrigations were evaluated in this study with 4 days' irrigation intervals (20 …”

“…However, few studies have done about wastewater flow on the soil surface [17][18][19][20][21][22][23][24].Thus in this study flow hydraulic of treated wastewater in furrow irrigation was studied by parameters consists of infiltration and advance, storage, depletion and recession phases and fresh water was used as control. Magnetic field effects were also investigated on flow hydraulic of treated wastewater by magnetized wastewater [25][26][27][28][29][30][31][32][33][34].…”