Behrouz SAFI, Mohamad Reza NEYSHABOURI, Amir Hossein NAZEMI

Water Application Uniformity of a Subsurface Drip Irrigation System at Various Operating Pressures and Tape Lengths

Subsurface irrigation has been the focus of attention mainly because of its low evaporation rate and deep percolation losses. Uniformity of water applications and its stability, however, are still a matter of controversy and deserve more investigation. An experiment was conducted at the research station of Tabriz University to evaluate discharge variation among emitters and uniformity after 3 years of operation at different pressures, as well as to determine the optimum length for irrigation tapes. Four hydraulic pressures, 50, 90, 150, and 200 kPa, 4 irrigation tapes 34 m long (used tape) installed at a depth of 10 cm, and 5 new irrigation tapes (unused) 34, 50, 80, 100, and 120 m long comprised the experimental treatments. The used tapes were chosen from a subsurface irrigation system that operated for 3 years for onion irrigation. The new tapes (unused) were the same as the used ones and were laid on the soil surface during the experiment. Emitter discharge and pressure were measured every 2 m along both the used and unused tapes at the above mentioned operating pressures, and data were analyzed to compute several uniformity criteria using traditional and ASAE EP458 methods. In both used and unused tapes, emitter performance (Vpf) at 150 kPa was better than at 50, 90, and 200 kPa. The maximum uniformity coefficient (UC) values of the unused and used tapes 34 m long were 96.9% and 91.8%, respectively. Considering the variation in UC with tape length and an engineering approach toward the performance of the system for used tape, the 80-m length was determined as a suitable length for irrigation tape. The result indicated that both traditional and ASAE methods are suitable for the evaluation of subsurface drip irrigation systems. The ASAE method, however, showed slightly lower uniformity in both unused and used tapes (1.6% and 3.65%, respectively).

Anahtar Kelimeler:

Subsurface drip irrigation, emitter discharge, uniformity coefficient, emitter performance

Water Application Uniformity of a Subsurface Drip Irrigation System at Various Operating Pressures and Tape Lengths

Keywords:

Subsurface drip irrigation, emitter discharge, uniformity coefficient, emitter performance,

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Alizadeh, A. 2001. Principles and Practices of Trickle Irrigation. Ferdowsi University, Mashad,Iran.
ASAE STANDARDS, 43rd ed. 1996. EP458. Field Evaluation of Microirrigation Systems. St. Joseph, Mich. ASAE: 756-761.
ASAE STANDARDS. 2005. EP405.1 FEB03. Design and Installation of Microirrigation Systems. ASAE, St. Joseph, Mich.
Ascough, G.W. and G.A. Kiker. 2002. The effect of irrigation uniformity on irrigation water requirements. Water SA, 28: 235-241.
Ayars, J.E., C.J. Phene, R.B. Hutmacher, K.R. Davis, R.A. Schoneman, S.S. Vail and R.M. Mead. 1999. Subsurface drip irrigation of row crops: A review of 15 years of research at the Water Management Research Laboratory. Agr. Water Manage. 42: 1-27.
Camp, C.R., J.T. Garrett, E.J. Sadler and W.J. Busscher. 1993. Microirrgation management for double-cropped vegetables in a humid area. Transactions of the ASAE, 36: 1639-1644.
Camp, C.R., E.J. Sadler and W.J. Busscher. 1997. A comparison of uniformity measure for drip irrigation systems. Transactions of the ASAE, 40: 1013-1020.
Camp, C.R. 1998. Subsurface drip irrigation: A review. Transactions of the ASAE, 41: 1353-1367.
Hills, D.J., M.A.M. Tajrishy and Y. Gu. 1989. Hydraulic consideration for compressed subsurface drip-tape. Transactions of the ASAE, 32: 1197-1200.
Kırnak, H., E. Doğan, S. Demir and S. Yalçın. 2004. Determination of hydraulic performance of trickle irrigation emitters used in irrigation system in the Harran Plain. Turk. J. Agric. For. 28: 223-230.
Mizyed, N. and E.G. Kruse. 1989. Emitter discharge evaluation of subsurface trickle irrigation system. Transactions of the ASAE, 32: 1223-1228.
Nakayama, F.S. and D.A. Bucks. 1986. Trickle irrigation for crop production- Design, Operation, and Management, Developments in Agricultural Engineering 9. Elsevier, New York.
Ortega, J.F., J.M. Tarjuelo and J.A. de Juan. 2002. Evaluation of irrigation performance in localized irrigation system of semiarid regions (Castilla-La Mancha, Spain): Agricultural Engineering International: CIGR Journal of Scientific Research and Development. 4: 1-17.
Phene, C.J., M.F. Blume, M.M.S. Hile, D.W. Meek and J.V. Re. 1983. Management of subsurface trickle irrigation systems. ASAE Paper No. 83-2598, ASAE, St. Joseph, Mich.
Phene, C.J., R. Yue, I. Wu, J.E. Ayars, R.A. Schoneman and B. Meso. 1992. Distribution uniformity of subsurface drip irrigation systems. ASAE, Paper No. 92-2569, ASAE, St. Joseph, Mich.
Sadler, E.J., C.R. Camp and W.J. Busscher. 1995. Emitter flow rate changes caused by excavating subsurface microirrigation tubing. In: Proceedings of the 5th International Microirrigation Congress. (Ed. F.R. Lamm) ASAE, St. Joseph, Mich. pp. 763-768.
Safi, B., M.R. Neyshabouri, A.H. Nazemi, S. Masiha and S.M. Mirlatifi. 2007. Subsurface irrigation capability and effective parameters on onion yield and water use efficiency. Journal of Scientific Agricultural. 1: 41-53.
Shaviv, A. and G. Sinai. 2004. Application of conditioner solution by subsurface emitters for stabilizing the surrounding soil. J. Irrig. Drain. Eng. 130: 485-490.
Warrick, A.W. and U. Shani. 1996. Soil-limiting flow from subsurface emitters. II: Effect on uniformity. J. Irrig. Drain. Eng. 122: 296- 300.
Wu, I-Pai. and H.M. Gitlin. 1979. The Manufacturer’s coefficient of variation of emitter flow for drip irrigation. University of Hawaii at Manoa U.S.D.A. Cooperating: 1-3.