Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/27/2012
Publication Date: 9/27/2012
Citation: Evett, S.R., Schwartz, R.C., Butaev, M. 2012. Irrigation science and water quality challenges in Ukbekistan.[abstract]American Association for the Advancement of Science-Academy of Sciences of Uzbekistan joint workshop, U.S. Life Sciences Collaboration:Defining the Opportunites, Tashkent, Uzbekistan, September 27-29, 2012.
Technical Abstract: Agriculture in Uzbekistan is nearly entirely irrigated due to the semi-arid to arid climate. Similar conditions exist in the U.S. Southern High Plains, and several irrigation crops are important to both regions, including cotton, maize and winter wheat. This presentation discussed cooperative research between the USDA-ARS Conservation & Production Research Laboratory, Bushland, Texas and the Uzbekistan Cotton Growing Research Institute (UCGRI), Tashkent, Uzbekistan that occurred from 1999 to present. Early research focused on methods for determining crop water use and water and nitrogen use efficiency using nuclear techniques including the neutron probe, and N-15 and C-13 isotopes. Neutron probe calibration methods and equipment developed at Bushland were used in Uzbekistan to develop instrument calibrations at six research stations of the UCGRI. Later studies focused on contrasting irrigation application methods, namely drip and furrow irrigation, to find the best irrigation scheduling regimes and the yields and water use efficiencies possible with each application method. Drip irrigation was shown to outperform furrow irrigation in both yield and water use efficiency. Water use, yield and water use efficiencies of cotton, maize and winter wheat were determined. More recently, studies focused on use of limited tillage and permanement beds as opposed to conventional tillage, both under irrigation. Those studies found that the plentiful crop residues produced under irrigation were difficult to deal with in a limited tillage scheme, which required several years of learning to produce acceptable crop stands and yields. Research is still underway to determine how best to implement limited tillage with irrigation. Research results generally confirmed and extended those from research conducted at Bushland. Throughout most of the studies, cooperative research on water quality was conducted in collaboration with the Uzbekistan Veterinary Research Institute. Tests for parasites and pathogenic bacteria were conducted on irrigation waters sampled from the supply canals, from runoff from irrigated fields, and from irrigation water that had passed through manure composting pits at the head of fields. Both a country-wide survey and a survey in the Samarkand Province were conducted at separate times. Some parastic helminths were found in runoff and manure pit waters, but not in irrigation canals. Pathogenic bacteria were not found. The presentation finished with a discussion of the structure of ARS and particularly of the ARS National Program 211 in water resource management. The main ARS laboratories conducting water resource research were described, and opportunites for collaborative research on problems common to both the USA and Uzbekistan were explored.