- #NITROGEN VOLATILIZATION LOSSES USING APSIM HOW TO#
- #NITROGEN VOLATILIZATION LOSSES USING APSIM MANUAL#
Drag a Depth graph from the Graph toolbox onto the outputfile.Ģ. This is why we included no3 and nh4 as layered variables and not just as totals.ġ. Layered variables are always held in arrays. Depth plots require two values, the “dlayer” variable which holds the depth of each layer and at least one other layer variable. We will create a depth plot to help visualise this. Let’s look at the distribution of nitrate through the soil profile at 21 days after fertilisation, and again at 5 months. Create a new graph of day vs rain, dnit(right axis), esw and NO3Total.įrom this chart you can see that significant nitrogen is lost via denitrification when large amounts of nitrate are available in saturated soil conditions.Įxploring Vertical Movement of Nitrate through the Soil Profile Create a graph of day vs urea, total ammonium and total nitrate, changing the name to Nitrogen. Change reporting frequency to ‘end_day’, and run the simulation.ġ4. We are also outputting the individual layers.ġ3. Here we are summing the values over the profile to return one value then using an alias to rename the variable. Each value in the array corresponds to a layer in the soil. Enter the following variables into the outputfile Variable list: Component Remove all outputfile Variables except Date (the first one). Leave the ‘Don’t add fertiliser if N in top 2 layers exceeds (kg/ha)’ property as it is, but set the ‘Module used to apply the fertiliser’ in the above manager rule to be ‘fertiliser’.ġ2. Change the fertiliser management parameters to apply 100 kg/ha of urea_N on 10-Jan. You will find it in the Management toolbox under Manager (common tasks).ġ1. Drag a ‘Fertilise on fixed date’ script to the Manager folder. Remove all manager scripts under the Manager folder, but leave the folder itself.ġ0. Make the depth equal to the entire soil profile (check Water node for the profile depth).ĩ. Don’t forget to change units to kg/ha (right click the column header). Set starting nitrogen to 19kg/ha NO3 and 0 NH4, evenly distributed. Set starting water to 50% full, evenly distributed:Ĩ.
#NITROGEN VOLATILIZATION LOSSES USING APSIM HOW TO#
Add the heavy clay soil from the Training toolbox (see module 1 if you’re not sure how to do this).ħ. Change the starting date to and the end date to Ħ. To do this, click the met module, then click ‘Browse’ (in right hand panel) and select Dalby weather (C:\Program Files(x86)\Apsim-r\Examples\MetFiles\ by default).ĥ. This simulation will use a different weather file. Rename the simulation to ‘Nitrogen Cycle’.Ĥ. Start a new simulation based on Continuous Wheat.apsim.Ģ. This simulation will introduce editing a simple Manager rule and to more advanced features of graphing simulation results.ġ. In this exercise you will observe the cycle of fertiliser nitrogen in a fallow situation urea to ammonium, ammonium to nitrate and the loss of soil nitrate via denitrification.
Scenario: Kingsthorpe Soil Water Evaporation Project.Create your own or Add someone elses toolbox.Construct a factorial simulation in the User Interface.
#NITROGEN VOLATILIZATION LOSSES USING APSIM MANUAL#
Training Manual (West Africa – English and French).The effect of residue cover on soil water storage.Cropping sequence simulations (rotations).