Post on 31-Dec-2015
description
352.T1
Model Agricultural Core Curriculum: SupplementUniversity of California, Davis
Irrigation Terminology
Soil Moisture Conditions
Saturation Field Capacity Wilting Point
Too Wet Ideal Too DryNo air space. Balance between No available
air - water - soil. water.
352.T2
Model Agricultural Core Curriculum: SupplementUniversity of California, Davis
Irrigation Terminology
Waterlogging
Normal root zone
Ground line
No root development Water-logged soil
352.T3
Model Agricultural Core Curriculum: SupplementUniversity of California, Davis
Irrigation Terminology
Water Holding Capacity (WHC)
Coarse Textured Soil Fine Textured Soil
Low WHC
The larger the soil particle size, the lower the water holding capacity.
High WHC
352.T4
Model Agricultural Core Curriculum: SupplementUniversity of California, Davis
Irrigation Terminology
Water Intake Rate
Coarse Soil Fine Soil
Generally, the larger the soil particle size, the faster the water intake rate.
High Water-Intake Rate Low Water-Intake Rate
352.T5
Model Agricultural Core Curriculum: SupplementUniversity of California, Davis
Irrigation Terminology
Field Capacity
• When all of the excess water has drained from the soil it is said to be at Field Capacity (FC).
352.T6
Model Agricultural Core Curriculum: SupplementUniversity of California, Davis
Irrigation Terminology
Wilting Point
• The point at which soil moisture is so low that plants can no longer pull water from it.
• Plants will die unless watered immediately.
352.T7
Model Agricultural Core Curriculum: SupplementUniversity of California, Davis
Irrigation Terminology
Permanent Wilting Point
• The point at which the plant has lost so much water that it will not revive even if watered immediately.
352.T8
Model Agricultural Core Curriculum: SupplementUniversity of California, Davis
Irrigation Terminology
Available Water (AW)
• The water which is available to the plants.
• AW is found by subtracting the wilting point measurement from the field capacity measurement.
AW = FC - WP