Author
Vories, Earl | |
TACKER, P - UNIVERSITY OF ARKANSAS | |
WILSON, C - UNIVERSITY OF ARKANSAS | |
RUNSICK, S - UNIVERSITY OF ARKANSAS | |
BRANSON, J - UNIVERSITY OF ARKANSAS |
Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 12/2/2005 Publication Date: 12/20/2006 Citation: Vories, E.D., Tacker, P.L., Wilson, C., Runsick, S., Branson, J. 2006. Water use measurements from the Arkansas rice research verification program [abstract]. Proc. 31st Rice Technical Working Group. p. 136. (CD-ROM) Interpretive Summary: Technical Abstract: In 1983, the Cooperative Extension Service established an interdisciplinary rice educational program that stresses management intensity and integrated pest management to maximize returns. The purpose of the Rice Research Verification Program (RRVP) was to verify the profitability of University of Arkansas recommendations in fields with less than optimum yields or returns. The goals of the program are: (1) to educate producers on the benefits of utilizing University of Arkansas recommendations to improve yields and/or net returns; (2) to conduct on-farm field trials to verify research-based recommendations; (3) to aid researchers in identifying areas of production that require further study; (4) to improve or refine existing recommendations which contribute to more profitable production; and (5) to incorporate data from RRVP into Extension educational programs at the county and state level. The RRVP is supported by producer checkoff funds through the Arkansas Rice Research and Promotion Board. Since 1983, the RRVP has been conducted on over 240 commercial rice fields in more than 30 rice-producing counties in Arkansas. The RRVP fields and cooperators are selected prior to the beginning of the growing season. Cooperators agree to pay production expenses, provide expense data, and implement university recommendations in a timely manner from planting to harvest. A designated county agent from each county assists the RRVP coordinator in collecting data, scouting the field, and maintaining regular contact with the producer. Management decisions are made based on current University of Arkansas recommendations. During the first eight years of the program (1983 - 1990), flowmeters were placed on the water supplies of 42 of the program fields and water use was recorded during the permanent flood period (i.e., excluding any flushes necessary for germination and/or herbicide activation). Irrigation water use ranged from 381 to 1714 mm (15 to 67.5 in), with an average of 879 mm (34.6 in). Water use did not vary greatly among predominant soil types, with nine clay fields using an average of 902 mm (35.5 in), while 25 silt loam fields used an average of 907 mm (35.7 in). After eight years, the water-use data were collected less frequently. However, beginning in 2003 a new effort was begun to see whether water use had changed very much over the years. In addition to twenty years of the RRVP, there were other reasons to believe that water use may have decreased: many of the cultivars being produced had shorter growing seasons than older cultivars, and following a multi-year educational program many producers had adopted multiple-inlet irrigation, which had been shown to reduce water use by 24% below that of conventional flooding. Water-use data were collected from ten fields in 2003, along with ten in 2004 and 13 in 2005. Irrigation water use ranged from 460 to 1435 mm (18.1 to 56.5 in), with an average of 780 mm (30.7 in). Again, water use did not vary greatly among predominant soil types, with 17 clay fields using an average of 781 mm (30.8 in), while 13 silt loam fields used an average of 763 mm (30.1 in). Finally, long-term water use may be more improved than the three-year (2003 - 2005) averages suggest. The 2005 rice growing season was extremely dry. Most producers had to flush their fields at least once before applying the flood, after not needing to flush during the two previous seasons. In addition, several producers commented that they had a harder time maintaining a flood in 2005 than they could ever remember. The annual averages were 724 mm (28.5 in) for ten fields in 2003, 621 mm (24.4 in) for ten fields in 2004, and 946 mm (37.2 in) for thirteen fields in 2005. Additional data collected in future growing seasons should indicate whether the values for 2005 were unusually high and how much irrigation water use for rice production has |