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<br />l\,) <br />f0 <br />00 <br />0-, <br /> <br />Intake family, slope, soil, and acreage data were measured in the field <br />or calculated. Data collected is found in Appendix C "Measurement and <br />Calculation". The advance time is the time taken for water to advance <br />from the top (inflow measuring point) to the bottom of the field where <br />the outflow weir was located. The infiltrated depth was obtained as the <br />difference between measured flow (gross application) and the measured <br />runoff for irrigation event. <br /> <br />Precipitation data shown in Table 2 is measured from planting date to <br />harvest date. The amounts in these columns vary for each site because <br />o,f the length of record for different crops. Some of the variations are <br />due in part to the different crops and climatic variations at each <br />location. Among perennial crops, soil water deficit data varies for the <br />same crop at different sites because of differences in crop cover and <br />maturity. Stress factors due to soil moisture deficit also affects SWD <br />values (refer to Appendix C for SWD definition) for both annual and <br />perennial crops. <br /> <br />Under individual irrigation summaries, the ETa and precipitation data <br />are shown in the tables as a value for each irrigation event. The value <br />shown is the calculated ET for the particular crop from the time of <br />previous irrigation event; or for the first irrigation event it is ETa <br />from the beginning of plant growth to the date of the irrigation event. <br /> <br />The soil moisture deficit before irrigation was determined from the <br />daily water budget computer program. All sites were probed before the <br />start of the irrigation season to estimate soil moisture deficit before <br />irrigation. If the infiltrated depth for a particular irrigation event <br />exceeded the soil moisture deficit before irrigation, then the soil <br />profile is assumed to be full and there is no soil moisture deficit <br />after irrigation. Excess beyond what is needed to replace the soil <br />water deficit is considered to be deep percolation. <br /> <br />In 1990, the water budget program was updated to more accurately <br />estimate deep percolation for annual crops. In the past, deep <br />percolation for the first irrigation and or pre-irrigation was <br />considered to be any amount that was in excess of that required to fill <br />up the first foot of soil. The full root profile was not taken into <br />account. With this method, deep percolation estimates were higher than <br />what they should have been. The updated program takes full rooting <br />profile into consideration. All previous data from 1986 to 1989 was re- <br />processed using the updated program to get a better estimate of deep <br />percolation, soil moisture and ETa etc. <br /> <br />The seasonal and individual application efficiency data shown in Table 2 <br />and individual site summaries is the ratio of water used beneficially to <br />the total irrigation water applied. The calculation is discussed in <br />Appendix C. <br /> <br />Table 2 and individual site summary tables show that water budgets <br />differed greatly for different sites. <br /> <br />Deep Percolation: The seasonal deep percolation losses for the eight <br />sites are shown in Table 2 which has been extracted from individual <br />irrigation summaries. These are reported as acre inches per acre and as <br />a percentage for each individual irrigation event. <br /> <br />9 <br />