Skip to Main Content
In this study, a typical on-farm water storage pond with an area of 5.06 ha and an average depth of 2 m was selected (Figure 2). This pond size reflects the average field conditions near Macon, East Mississippi. Two simulation scenarios were performed in this study. The first scenario was chosen to predict the annual patterns of pond hydrologic processes under conditions without using pond water for soybeans irrigation. The second scenario was selected to estimate the annual patterns of pond hydrological processes with using pond water for soybeans irrigation. In this second scenario, all of the simulation conditions and input parameters were the same as those used in the first scenario except for the pond water used to irrigate for different soybeans land sizes. Table 1 lists the number of irrigations, irrigation rate, and total irrigation for each year and their 10-year averages during the growth of the soybeans in East Mississippi. These irrigation data were obtained from our previous study (Feng et al. 2016) and were used as model inputs in this study. It should be noted that the irrigation rate was 2.54 cm/d (or 1 inch/d), which is a very common practice in East Mississippi. Comparison of the simulation results from the two scenarios allowed us to evaluate the impacts of irrigation upon pond hydrological processes and to determine the ratio of pond size to irrigated soybeans land. The simulation period was 10 years started on the first day of 2002 and terminated at the end of 2011, for each scenario an hourly time step was used. All of the input parameters for these scenarios are given in Table 2.
Figure 2

Location of a pond (a) and its dimension (b) selected for simulation.

Figure 2

Location of a pond (a) and its dimension (b) selected for simulation.

Table 1

Irrigation data used as model input in this study

YearNumber of irrigationsIrrigation rate each time (mm)Total irrigation (mm)
2002 25.4 76.2 
2003 25.4 50.8 
2004 25.4 25.4 
2005 25.4 127.0 
2006 12 25.4 304.8 
2007 25.4 203.2 
2008 25.4 177.8 
2009 25.4 50.8 
2010 25.4 101.6 
2011 25.4 177.8 
10-year average 5.1 25.4 129.5 
YearNumber of irrigationsIrrigation rate each time (mm)Total irrigation (mm)
2002 25.4 76.2 
2003 25.4 50.8 
2004 25.4 25.4 
2005 25.4 127.0 
2006 12 25.4 304.8 
2007 25.4 203.2 
2008 25.4 177.8 
2009 25.4 50.8 
2010 25.4 101.6 
2011 25.4 177.8 
10-year average 5.1 25.4 129.5 

The data were obtained from Feng et al. (2016) and the number of irrigations each year was determined based on rainfall amount and soil moisture regime.

Table 2

Input parameter values used in this study

ParameterValueSource
Hydrological conditions 
 Curve number 89 Rawls et al. (1992)  
 Hourly rainfall (cm/h) Time series measurements Local weather station 
 Effective land area for runoff (cm215,297,117,277 (or 153 ha) Estimated 
 Pond drainage (cm3/h) 0.00005 Estimated 
 Lateral seepage (cm3/h) Estimated 
 Evaporative coefficient K1 in Equation (3) 0.0022 Calibrated 
 Hourly solar radiation (kJ/cm2/h) Time series data Measured 
 Hourly air temperature (°C) Time series data Measured 
 Pumping for irrigation rate (cm3/h) Time series measurements Estimated 
 Irrigation area (cm2varied for different ratios Assumed 
Pipe flow 
 Manning roughness coefficient, n 0.01 Maidment (1992)  
 Bottom slope of pipe 0.003 Measured 
 Radius of the pipe (cm) 60 Measured 
Pond Matrix 
 Bottom pond width, a (cm) 1.60E + 04 Measured 
 Bottom pond length, b (cm) 2.02E + 04 Measured 
 Maximum top pond width, Wm (cm) 2.00E + 04 Measured 
 Maximum top pond length, Lm (cm) 2.53E + 04 Measured 
 Maximum pond height, Hm (cm) 2.00E + 02 Measured 
 Pumping low limit of pond level (cm) 5.00E + 01 Measured 
 Maximum pond volume (cm36.51E + 10 Calculated 
 Initial pond volume (cm36.50E + 10 Assumed 
 Pipe spill level 1.80E + 02 Measured 
 Pond spill level 1.99E + 02 Measured 
ParameterValueSource
Hydrological conditions 
 Curve number 89 Rawls et al. (1992)  
 Hourly rainfall (cm/h) Time series measurements Local weather station 
 Effective land area for runoff (cm215,297,117,277 (or 153 ha) Estimated 
 Pond drainage (cm3/h) 0.00005 Estimated 
 Lateral seepage (cm3/h) Estimated 
 Evaporative coefficient K1 in Equation (3) 0.0022 Calibrated 
 Hourly solar radiation (kJ/cm2/h) Time series data Measured 
 Hourly air temperature (°C) Time series data Measured 
 Pumping for irrigation rate (cm3/h) Time series measurements Estimated 
 Irrigation area (cm2varied for different ratios Assumed 
Pipe flow 
 Manning roughness coefficient, n 0.01 Maidment (1992)  
 Bottom slope of pipe 0.003 Measured 
 Radius of the pipe (cm) 60 Measured 
Pond Matrix 
 Bottom pond width, a (cm) 1.60E + 04 Measured 
 Bottom pond length, b (cm) 2.02E + 04 Measured 
 Maximum top pond width, Wm (cm) 2.00E + 04 Measured 
 Maximum top pond length, Lm (cm) 2.53E + 04 Measured 
 Maximum pond height, Hm (cm) 2.00E + 02 Measured 
 Pumping low limit of pond level (cm) 5.00E + 01 Measured 
 Maximum pond volume (cm36.51E + 10 Calculated 
 Initial pond volume (cm36.50E + 10 Assumed 
 Pipe spill level 1.80E + 02 Measured 
 Pond spill level 1.99E + 02 Measured 
Close Modal

or Create an Account

Close Modal
Close Modal