Assessment of a newly implemented irrigated area (Lerma Basin, Spain) over a 10-year period. I: Water balances and irrigation performance

 

Authors
Garc?a Gariz?bal, Iker
Format
Article
Status
publishedVersion
Description

Implementation of irrigated agriculture is common in semi-arid areas around the world. An assessment of irrigation performance is presented herein for a hydrological basin with an area of 7.38 km2, representative of pressurized irrigated areas within the Ebro Basin (Spain). The study covers ten hydrological years, comprehending periods before (2004?2005), during (2006?2008) and after (2009?2013) transformation to irrigated land. Water balances were carried out for each of the 55 agricultural plots and for the totality of irrigable area. Once the water balance for the basin is validated, indicators of irrigation performance were obtained from the soil water balances for the vegetative cycle of the crops in each plot. Water balances presented good results, with balance errors below 10.0% for most of the studied years and an error of 1.2% across the entire study period. After implementation of irrigation, irrigation became the main water input to the basin (approximately 60%) whereas actual evapotranspiration accounted for the major output (approximately 70%). Irrigation efficiency reached 76.1%, while the losses of efficiency were due to evaporation and wind drift of sprinkler irrigation (13.5%) and drainage fraction (10.4%). A water deficit of 17.8% was estimated. The irrigation efficiency increased (1.05% year?1), while the irrigation drainage fraction decreased (0.95% year?1). However, improvements in irrigation performance were not guaranteed as water deficits also increased (0.95% year?1). Optimal water use could be achieved through adequate design of irrigation schedules, i.e., irrigation rates adjusted to the requirements of crops and minimization of evaporation and wind drift losses.
http://www.sciencedirect.com/science/article/pii/S0378377415001419

Publication Year
2015
Language
eng
Topic
IRRIGATION
EFFICIENCY
IRRIGATION
DRAINAGE
FRACTION
Repository
Repositorio SENESCYT
Get full text
http://repositorio.educacionsuperior.gob.ec/handle/28000/3000
Rights
openAccess
License
closedAccess