WSP02111 - Laserfiche WebLink

Home Browse Search

w o ~') CO .~:t/~ 8. Whe....e improved i........igatlon systems have been installed, the deep perco I at i on losses can be ....educed substant i a II y by p....ope.... management of individual ir....igation events. Reducing set time <numbe.... of hou....s per set) and waiting longer between ir....igations (ir....,gation scheduling) would ....educe deep per c 0 I at ion s i g n i f i can t.l y, and a Iso i n c I'" e as e . i I'" I'" i gat i. 0 n efficiency. c. Summary Of Water Budget, Deep Pe....colation And Application Efficiency .Water Budget: The ....esults of the 1991 i.........igation monito....ing evaluations from the 23 sites are presented in individual site summa....ies located in the Appendix, Table 2 summarizes the seasonal data obtained from the 23 ir....igation monito....ing sites and also shows the breakdown of data by crops and ir....igation systems. The data on Table 2 ....ep....esent the total flo'.oJs on and off the field, total deep pe....colation and ET fo.... all i........igations du....ing the 1991 i........igation season. The info....mation on Table 2 has been extracted f....om individual iF~igation summaries provided in Appendi~ 0; .~<~;.~. During the 1991 irrigation sea,son, all irrigation events, incl.udi.ng pre-irrigation events were monitored for al I sites with the exception of sites 49 and 50 (compa....ison sites). At these sites, the first (fall i r,...i gat i on) was not mon i tOred s i nee it was not known at that time whethe.... the Bureau of Reclamation funding would go through. The sites we....e established in sp....ing. The info....mation on intake family, slope, soil, ac'reage etc. shown on individua.1 summaries in Appendi.x B was obtained from SCS..files. Otherc data we....e measured in the field or calculated.. .Data collected is explained in detai.l under "Measurement and Calcu.lation" section of Appendix C. The advance time shown in individual summa....ies is the time taken for wate.... to advance from the top (inflow measu....ing point) to the bottom of the field where the outflow weir was located. The infi Itrated depth was obtained as the difference between measu....ed flow <gross appl ication) and the measured ....unoff for ir....igation event. The p....ecipitation and ETa data shown on Table 2 a....e measu....ed from planting date to harvest date, The amounts in these columns vary for each site because of the I ength of reco....d fo..... d i ffe....ent crops. Some .of the va....iations are due in part to the diffe....ent crops and climatic variations at each location. Among perennial c....ops, ETa data vary fo.... the same c....op at different sites (e.g. sites 13 and 51) because of differences in c....op cover and matu....ity. Stress facto....s due to soi I moisture deficit also affect ETa values <....efer to Appendix C fo.... ETa definition) fo.... both annual and pe....ennial c....ops. 13