Abstract:
Often low intake rate soils need special consideration when
applying water during an irrigation. Surface flooding for extended
periods may cause adverse crop growth conditions. Properly
designed sprinkler systems often eliminate irrigation problems,
because the application rate and quantity of water applied can be
readily controlled.
Research workers who have studied sprinkler irrigation disagree
on many things. Differences are found in the literature
concerning the procedures used to determine sprinkler distribution
uniformity and the optimum rate of application of water to the soil.
Several authors suggest that moisture movement within the soil
occurs after an irrigation. If trans location of moisture occurs, it
may be possible to use sprinkler system design specifications that
are less critical than those now in use. In order to determine the effect of sprinkler application rate
on the resulting soil moisture distribution it is necessary to have
criteria relating degree of ponding, crop cover, and slope of the
land to the uniformity of soil moisture. Experimental plots were
designed and prepared to study and relate these factors to each
other. Sprinkler distribution measurements were made to be used
in computing sprinkler uniformity. Using neutron equipment, soil
moisture determinations were made before the irrigation, one day
after irrigation, and three days after irrigation to determine the
effect of the irrigation.
Final analysis of the data from the experiment indicated that
there was not an optimum degree of ponding. In fact, ponding,
application rate, grade of plots, and crop cover did not appear to
appreciably affect the distribution of soil moisture after an
irrigation.
