A model for computing date palm water requirements as affected by salinity

Or Sperling, Or Shapira, Effi Tripler, Amnon Schwartz, Naftali Lazarovitch

Research output: Contribution to journalArticlepeer-review

19 Scopus citations

Abstract

Irrigation of crops in arid regions with marginal water is expanding. Due to economic and environmental issues arising from use of low-quality water, irrigation should follow the actual crop water demands. However, direct measurements of transpiration are scant, and indirect methods are commonly applied; e.g., the Penman-Monteith (PM) equation that integrates physiological and meteorological parameters. In this study, the effects of environmental conditions on canopy resistance and water loss were experimentally characterized, and a model to calculate palm tree evapotranspiration ETc was developed. A novel addition was to integrate water salinity into the model, thus accounting for irrigation water quality as an additional factor. Palm tree ETc was affected by irrigation water salinity, and maximum values were reduced by 25 % in plants irrigated with 4 dS m-1 and by 50 % in the trees irrigated with 8 dS m-1. Results relating the responses of stomata to the environment exhibited an exponential relation between increased light intensities and stomatal conductance, a surprising positive response of stomata to high vapor pressure deficits and a decrease in conductance as water salinity increased. These findings were integrated into a modified 'Jarvis-PM' canopy conductance model using only meteorological and water quality inputs. The new approach produced weekly irrigation recommendations based on field water salinity (2.8 dS m-1) and climatic forecasts that led to a 20 % decrease in irrigation water use when compared with current irrigation recommendations.

Original languageEnglish
Pages (from-to)341-350
Number of pages10
JournalIrrigation Science
Volume32
Issue number5
DOIs
StatePublished - 1 Jan 2014

ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Water Science and Technology
  • Soil Science

Fingerprint

Dive into the research topics of 'A model for computing date palm water requirements as affected by salinity'. Together they form a unique fingerprint.

Cite this