CPP CPP Irrigation & Water Management 1 — Questions and Answers
Question 1: Which irrigation method delivers water directly to the root zone and is most efficient for landscape plants in arid US regions?
- Flood irrigation
- Drip irrigation (Correct answer)
- Overhead sprinkler
- Furrow irrigation
Correct answer: Drip irrigation
Drip irrigation delivers water directly to the root zone, minimizing evaporation and runoff in arid climates.
Question 2: What is the term for the amount of water lost from soil and plant surfaces combined, used to calculate irrigation scheduling?
- Transpiration
- Evaporation
- Evapotranspiration (ET) (Correct answer)
- Percolation
Correct answer: Evapotranspiration (ET)
Evapotranspiration (ET) combines soil evaporation and plant transpiration and is the primary metric for irrigation scheduling.
Question 3: A plant's water requirement is best described by which coefficient when adjusting reference ET for landscape use?
- Crop coefficient (Kc) (Correct answer)
- Manning's coefficient
- Irrigation efficiency factor
- Field capacity index
Correct answer: Crop coefficient (Kc)
The crop coefficient (Kc) adjusts reference ET to reflect the actual water needs of a specific plant species or landscape.
Question 4: Which soil property most directly determines how quickly irrigation water infiltrates and moves through the profile?
- Soil pH
- Organic matter content
- Soil texture and structure (Correct answer)
- Cation exchange capacity
Correct answer: Soil texture and structure
Soil texture and structure determine pore size distribution, which controls infiltration rate and water movement through the soil profile.
Question 5: What does 'distribution uniformity' (DU) measure in an irrigation system evaluation?
- Total water applied per cycle
- Consistency of water application across the irrigated area (Correct answer)
- Pressure at the system head
- Number of emitters per zone
Correct answer: Consistency of water application across the irrigated area
Distribution uniformity measures how evenly water is applied across the irrigated area, with higher DU indicating more consistent coverage.
Question 6: Which backflow prevention device is required by most US codes when an irrigation system is connected to a potable water supply?
- Gate valve
- Ball valve
- Pressure vacuum breaker (PVB) or reduced-pressure zone (RPZ) device (Correct answer)
- Check valve only
Correct answer: Pressure vacuum breaker (PVB) or reduced-pressure zone (RPZ) device
A pressure vacuum breaker (PVB) or reduced-pressure zone (RPZ) assembly is required to prevent irrigation water from contaminating the potable water supply.
CPP CPP Irrigation & Water Management 1
Which irrigation method delivers water directly to the root zone and is most efficient for landscape plants in arid US regions?