Subsurface Drip Irrigation of Bermudagrass with
Saline Water
- D. A. Devitt
W. W. Miller
ABSTRACT
In many areas of the United States, increased
population growth is placing greater demands on available water resources.
Therefore, investigations into the use of alternative irrigation methods and lower quality
waters for agricultural and horticultural crops deserves greater attention. The use
of subsurface drip irrigation has shown considerable promise in this regard. Whether
or not this method combined with the use of lower quality waters could be used on
turfgrass was the focus of this study.
The effects of different subsurface drip line spacing (61, 91, and 122
cm (24, 35.8, and 48 in., respectively) on bermudagrass (Cynodon dactylon L.
Pers.) response for two soils (sandy loam and clay) when using saline water (EC = 2.2
ds/m) for irrigation was investigated. Plant response (relative yield, root length
density, and canopy temperature) along with the salt and water distribution between drip
line spacings was measured over a 15-month period.
The results of this experiment showed that salinity was the major
limiting factor for turf production under subsurface drip irrigation in the sandy loam
soil, whereas in the clay soil the major limiting factor was availability of soil
moisture. Linear relationships were found for increased average salinity over the
rootzone and decreased average soil water content with distance from the drip lines.
Subsequently, canopy temperature increased with distance from the drip lines.
Relative yields were described best by a parameter that included both salinity and
soil water content (ECe/Ø.
Yields were found to be high until an ECe/Ø threshold was reached and then yields declined quickly thereafter. In this
experiment only the 61 cm spacing in the sandy loam soil gave an acceptable salt and water
distribution and turf response when compared to the surface irrigated controls.
These findings suggest that when using subsurface drip irrigation on turfgrass in
conjunction with saline water, drip spacing cannot be maximized to reduce the dollar
investment. Instead, subsurface drip lines should be spaced at a distance in which
set leaching fractions can achieve high soil water content uniformity and decreased
buildup of salts in the active root zone.
Article published in the Applied Agricultural
Research Vol.3, No. 3, pp. 133-143 1988
for more information please contact Dr. Dale Devitt
