Location: Water Management Systems Research
Project Number: 3012-13000-007-05-S
Project Type: Specific Cooperative Agreement
Start Date: Sep 1, 2013
End Date: Aug 31, 2018
The Objective section is expanded under Amendment #1 as follows: (1) Understand the effect of spatial variability of soil properties on managing inputs such as irrigation and modeling crop productivity; and (2)Simulate the effects of irrigation and fertility management on greenhouse gas emissions from irrigated corn.
The Approach section is expanded under Amendment #1 as follows: (1) Field estimated water holding capacity at the ARS Limited Irrigation Research Farm varies from plot to plot and from year to year. It is important to separate the effects of soil property variability on crop yield from the treatment effects (i.e., irrigation scheduling). The impacts of variability will be modelled and analyzed using the Root Zone Water Quality Model(RZWQM2); and (2) A new feature has been added to RZWQM2 to simulate GHG emission under various management practices. A preliminary study from ARDEC showed that the model is capable of simulating GHG emission in response to fertilizer application rate in irrigated corn. Further study is needed to evaluate the model for simulating GHG emissions for different fertilizer types. RZWQ2 will be used to simulate GHG emission with various fertilizer types (granular urea, urea ammonium nitrate (UAN), polymer coated urea, stabilized urea products containing nitrification and urease inhibitors (Super U and UAN+AgrotainPlus), and UAN containing a slow-release N source (N fusion)). The results of this study will be extended to LIRF to show irrigation effects on GHG emission.