Irrigation Modeling for Crops Flood Irrigation & Forage Crops Mohunnad Massimi Fellow Scholar at Florida A & M University Agronomist and Extension Officer at NCARE Master of Field Crop from JUST

Lecture Aug, 7 2017 Agricultural Eng Ass Zarqa Number of Targets: 10 Engineers

Irrigation Modeling is a Term

Irrigation Modeling Modeling is Scheduling. Scheduling is two terms !! Irrigation Time. Irrigation Amount.

Irrigation Simply ! Timing Amount

Why Modeling is important ? Crop Water Requirements. Drought Sensitive Stages of Crops. Drought and Salinity. Treated Waste Water.

Sensitive Stages Forage and green plants = after cut. Alfalfa. Egyptian Clover. Silage Corn. Forage Sorghum. Sudan grass. Rye grass.

Sensitive Stages Cereal grains and field crops = at time of flowering and tillering. Barley. Wheat. Triticale. Oat. Grain Sorghum and Corn.

Agronomy Science of Crops Production and Soil Management. Themes: Seeds, Irrigation, Fertilization, Rotations, Machinery, and Protection.

Seeds Irrigation Fertilization Rotation Machinery Protection Agronomy

Drought and Salinity = Fx (CC) !!

Irrigation Terms Mathematical Modeling. Soil Texture. Field Capacity %. Permanent Wilting Point %. Managed Allowable Depletion. Root Depth (cm) Drip Irrigation. Surface / Flood Irrigation. Sprinkler Irrigation. Irrigation Efficiency.

Mathematical Modeling Clay Silt and Loam Sand Texture Field Capacity (v%) Permanent Wilting Point (v%) Sand 10 5 Loamy Sand 12 Sandy Loam 18 8 Sandy Clay Loam 27 17 Loam 28 14 Sandy Clay 36 25 Silt Loam 31 11 Silt 30 6 Clay Loam 22 Silty Clay Loam 38 Silty Clay 41 Clay 42

Managed Allowable Depletion % = Percent of water available that taken by the plant. Usually MAD % around 30 – 50 %. It is an indicator to irrigate again.

Equations Net Irrigation Requirements = Managed Allowable Depletion % (Field Capacity % - Permanent Wilting Point %) * Root Depth NIR = MAD % (FC %-PWP%)*D. Gross Irrigation Requirement = Net Irrigation Requirement / Irrigation Efficiency % GIR = NIR / E%.

Example Silage Corn hybrid (DK70-01) grown in Florida . Calculate both net and gross irrigation requirements if you know that Managed allowable depletion was 30 %, soil is clay, and root depth is 91 cm. Flood Irrigation Efficiency is 60 %.

Amount mm per meter Square is irrigation depth. In Jordan it measured in m3 / du. At time of rain, there is another calculations. On May 2 2017 a rain amount of 2.62 mm dropped. How much your NIR will be now?

Timing is Interval Interval is number of days. Water Depth Stored in Soil = Gross Irrigation Requirement * Irrigation Efficiency %. WDS = GIR * E % Interval (days) = Water Depth Stored in Soil / Daily Requirements. Int = WDS / DR.

Timing Calculate daily irrigation intervals for forage sorghum hybrid (ss2010) if you know that gross irrigation requirement is 7 mm/pot using flood irrigation, and daily requirement is 8 mm.

Suggestions ! Lecture on : Irrigation Modeling Using Drip Irrigation in Vegetables (1 day) ? Training Course: Irrigation Modeling for Crops Production (3 days) ?