Drip and evaporation
Evett, Steven R., author
Colaizzi, Paul D., author
Howell, Terry A., author
Loss of water from the soil profile through evaporation from the soil surface is an important contributor to inefficiency in irrigated crop production. Residue management systems may reduce this evaporative loss, but cannot be used in all cropping systems. Choice of the irrigation system and its management also can reduce evaporative loss. In particular, subsurface drip irrigation limits soil surface wetting and can lead to an overall reduction in evapotranspiration (crop water use) of as much as 10%. The example presented shows that most of the water savings occur early in the season when crop cover is not yet complete. Because evaporation from the soil surface has a cooling effect on the soil in the root zone, irrigation methods that limit evaporation will result in smaller fluctuations in soil temperature and warmer soil temperatures overall. For some crops such as cotton, this has beneficial effects that include earlier root growth, better plant development and larger yields.
Presented at the Central Plains irrigation conference on February 16-17, 2005 in Sterling, Colorado.