Response of wheat to nitrogen fertilization, a data set to validate simulation models for nitrogen dynamics in crop and soil

An easily implemented agro-hydrological procedure with dynamic root simulation for water transfer in the crop–soil system: Validation and application

“…the soil pressure head at the permanent wilting point (h 3 = -15000 cm), and is unlimited for soil pressure head between h 1 (-1 cm) and (-500 cm) for a rapid transpiration (0.5 cm The model performance was evaluated using the statistical indices of the coefficient of determination (R 2 ), the root of the mean squared errors (RMSE) and the mean error (ME) (Bohne and Salzmann, 2002;Ritter et al, 2003;Merdum et al, 2006). (Groot and Verberne, 1991). The dataset, which was comprehensive including dynamic measurements of soil mineral nitrogen and water contents down the profile, and dry matter accumulations and nitrogen contents in various organs during growth, was widely used for testing fertilizer models at different levels (De Willigen, 1991).…”

“…The data used in the study was water related only and from two sites Table 2. Details of the experiments can be seen in Groot and Verberne (1991).…”

“…Although the crop was sown in October 1983, no measurements of soil water content down the profile were taken until 07 February, Since the soil water was unknown from the beginning of the experiments to the first measurements, we used the dates of the first measurement of soil water as the starting points in the simulations and set the measured soil water distributions down the profile as the initial conditions. The weather information used in the simulation periods, including daily minimum and maximum air temperatures, rainfall and global radiation, was measured and given in Groot and Verberne (1991). Soil water retention curves for different layers (0-40 and 40-100 cm) in the Bouwing experiment were obtained from a series of standard curves, while the curves for the PAGV experiment (0-25, 25-40 and 40-100 cm) were measured (Groot and Verberne, 1991).…”

“…The weather information used in the simulation periods, including daily minimum and maximum air temperatures, rainfall and global radiation, was measured and given in Groot and Verberne (1991). Soil water retention curves for different layers (0-40 and 40-100 cm) in the Bouwing experiment were obtained from a series of standard curves, while the curves for the PAGV experiment (0-25, 25-40 and 40-100 cm) were measured (Groot and Verberne, 1991). In the study we used van Genuchten functions (Eqs.…”

“…2, 3) to describe the soil water retention curves, and the corresponding parameter values were fitted (Table 5) using the RETC software developed by van Genuchten et al (1991), based on the data provided by Groot and Verberne (1991). Since there were layers of gravel at a depth of about 100-120 cm, which acted as drains, in the Bouwing experiment (Groot and Verberne, 1991), we calculated the soil domain down to 120 cm, and the boundary condition at the bottom was set as free drainage. In the PAGV experiment, the groundwater table was frequently measured and ranged from 86 to 173 cm below the surface.…”