What is NIR?
Net Irrigation Requirement (NIR) is the amount of irrigation water required by a crop to meet its water demand after accounting for effective rainfall and soil moisture contribution.
Standard Agronomy Formula
NIR = ETc − (ER + ΔS)
Where:
• ETc = Crop water requirement (mm)
• ER = Effective rainfall (mm)
• ΔS = Contribution from soil moisture (mm)
Enter Required Data
Key Notes:
• NIR is expressed in mm of water
• Used to calculate Gross Irrigation Requirement (GIR)
• Very important for irrigation scheduling & exam numericals
• NIR is expressed in mm of water
• Used to calculate Gross Irrigation Requirement (GIR)
• Very important for irrigation scheduling & exam numericals
Leave a Reply