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<br /><~d' <br /> <br />~ <br />l'-'l <br />m <br />lIIol <br /> <br />"", <br /> <br />""~.".,<.. <br /> <br />'.';": '"~-, <br /> <br />'"':;i~';' <br /> <br />located. The infiltrated depth was obtained as the difference . <br />. between measured flow (gross application) and the measured runoff <br />for irrigation event. <br /> <br />The precipitation and ETa data shown in Table 2 is measured from <br />planting date to harvest date. The a~ounts in these columns vary <br />for each site because of the length of record for different crops. <br />Some of the varia'tions' are due in part to the different crops and' <br />climatic variations.at each location. Amonq.perennial crops, ETa <br />data varies for the same crop. at different sites (e.g. sites 13 and <br />51) because of differences in crop cover and maturity. Stress <br />factors due to soil moisture deficit also affect5~ET.a values (refer <br />. "to _Appendix. C for -ETa. definition)" for" both annual .and perennial <br />crops. <br /> <br />Under individual irrigation summaries, the ETa and precipitation <br />data are shown in the tables' as a value for each irrigation event. <br />The value shown is the calculated ET for the particular crop from <br />the time of previous irrigation event; or for the first irrigation <br />event it is ETa from the beginning of plant qrowth to the date of <br />. the irrigation event; . . <br /> <br />The soil moisture deficit before irriqation was determined from the <br />daily water budget computer proqram. All sites.were probed be {ore <br />the start of the irrigation season to estimate soil moisture <br />deficit before irrigation. If the infiltrated depth for a <br />particular irrigation event exceeded the soil moisture deficit <br />before irrigation, then the soil profile is assumed to be full and <br />there is no soil.moisture deficit after irrigation. However., any <br />excess beyond what is needed to. fill up the soil prOfile is <br />considered to be deep percolation.- <br /> <br />In 1990, the water budget program was updated to more accurately <br />estimate deep percolation forannual,crops. In the past, deep <br />percola.tion for the first irrigat"ion and or pre-irrigation was <br />considered to be. any amount that was in excess of that required to <br />{ill up the first foot of soil; the full root profile was not taken <br />into account. With this method, deep percolation estimates were <br />higher than what they should.have been. The updated program takes <br />full rootinq profile into consideration.. 'All previous dat~ from <br />.1986 to 1989 was re-processed using the updated program tO'get a <br />better estimate of deep percolation, soil moisture and ETa, etc. <br />The seasonal and'individual application efficiency data shown in <br />Table 2 and individual site summaries is the ratio of water used <br />beneficially to the total irrigation water applied. The <br />calculation is discussed in Appendix c. <br /> <br />Table 2 and individual site summary tables show that water budget <br />differed greatly for different sites. All sites applied enough <br />water to meet crop requirements with the exception of sites 51 and' <br />56. Other sites such as 13, 16, 26, and 41 were under-irrigated <br /> <br />, . <br /> <br />.1 <br /> <br />15 <br />