3. Evaporation

Question 1

Preconditions for evaporation;

Answer 1

• Water
• Saturation deficit
• Tension gradient (atmosphere-> vegetation -> soil) (suction head)
• Energy (energy balance:sun)

Question 2

Factors affecting evaporation:

Answer 2

• meteorology: temperature, wind, humidity
• Water, soil: moisture and soil type
• vegetation: type, season, roots, age
• nutrient cycle: O2, CO2, light, nutrients

Question 3

Classification of methods to measure evaporation:

Answer 3

1. Water balance methods
2. Micrometeorological methods
3. Remote sensing methods
4. Plant-physiological methods

Question 4

Methods to calculate Potential Evapotranspiration from land (ETP)

Answer 4

Haude
Turc-Wendling
Penman
FAO-Grass reference

Question 5

Methods to calculate Actual Evapotranspiration (ETR) from land

Answer 5

• Drying functions

- Penman - Monteith

Question 6

Methods to calculate Potential Evapotranspiration from water (ETP)

Answer 6

Potential = Actual Evaporation

• Dalton
• Penman