Document Type : Original Article
Author
Assistant Professor, Agricultural Engineering Research Department, Agricultural and Natural Resources Research Center Semnan province (Shahrood), AREEO, Shahrood, Iran.
Abstract
Introduction
Alfalfa is irrigated by drip, strip, Furrow and rain irrigation methods. Surface irrigation methods are unjustifiable and not economical due to the low potential of irrigation efficiency in dry areas. Rain irrigation methods cannot be justified in hot and dry areas due to high evaporation and high water requirement of alfalfa. Alfalfa is a plant whose leaves are sensitive to burns caused by poor quality water as a result of water spraying in the rain irrigation method (Hengeller, 1995). Micro irrigation methods (surface and subsurface drip) are among the alternative methods of rain methods. The subsurface drip irrigation method has not been developed in Iran due to the existence of ambiguities and some dark and unclear points regarding its efficiency for crops (clogged outlets, salt accumulation, risk of blockage of pipes by roots). These concerns require that before any development of subsurface drip irrigation method for different crops, necessary researches should be done in this field. Therefore, conducting any research on the efficiency of this method for alfalfa, which is a valuable fodder plant but requires a lot of water, seems necessary. This research was conducted with the aim of investigating the effect of subsurface drip irrigation method on alfalfa yield, the amount of water consumed and determining the appropriate distances and depths for sub-pipes.
Methodology
In order to investigate the effect of installation depth and distance of irrigation strips (laterals) in subsurface drip irrigation method on yield and water use efficiency in alfalfa cultivation, a study was conducted for two years on the farm of Damghan Agricultural Research Station. The design was implemented in the form of split strips based on randomized complete blocks with two factors and three replications. Factors included: 1- Distance of irrigation strips from each other in three levels (80, 100 and 120 cm) 2- Depth of installation of irrigation strips in two levels (30 and 45 cm below the soil surface). Depth of strips installation was considered as the main factor and distances as the sub-factor. The length of each experimental plot was 60 m and the width of the plots for the distances of 80, 100 and 120 cm were selected as 4, 5 and 6 m, respectively. Strips irrigation with a with a diameter of 20 mm with a discharge of 1.6 (lit/hr) and a distance of 60 cm for each dropper were selected. After preparing the ground and sowing the seeds, the subsurface irrigation pipes were placed (according to the treatments) with using the machine. Irrigation water was calculated by Penman-Monteith method and was given to the plant with an irrigation cycle of 4 days.
Results and Discussion
The results showed that the effect of pipe spacing on product yield (dry matter) and water use efficiency was significant, but the effect of pipe installation depth on yield and water use efficiency was not significant. The interaction effect of distance and depth of tapes irrigation on crop yield and water use efficiency was significant. There was no significant difference between crop yield in treatments with lateral distance of 80 and 100 cm. With increasing lateral distance from 80 to 120 cm, crop yield decreased sharply. Due to the yield of treatments and the cost of subsurface drip irrigation, the treatment of lateral distance of 100 and depth of 45 cm was suggested as the superior treatment.
Conclusions
The subsurface drip irrigation method for perennial crops is one of the efficient and appropriate methods. This method has a much higher efficiency than other irrigation methods due to the reduction of evaporation losses and the increase of irrigation efficiency especially in arid and semi-arid areas. The non-interference of irrigation in this method with the traffic of agricultural machines (especially during harvest) increases the ability and functionality of this method. But one of the problems of this method is the damage of rodents to the sub-pipes under the soil surface, which makes it difficult to determine the places of damage and repair them. Based on the results of this research, to prevent the damage of rodents, it is recommended to fight against these rodents and also to increase the installation depth of secondary pipes up to 50 cm. Clogging of droppers caused by poor filtration performance and penetration into and around the pipes are other problems of this method. To avoid these problems, it is recommended to inject acid and herbicide regularly into the irrigation system.
Keywords
Main Subjects
Ayars, J.E., Fulton, A. and Taylor, B. 2015. Subsurface drip irrigation in California-Here to stay?. Agricultural Water Management. (157) 39–47.
Attram, J., Acharya, S., Smith, E. and Thomas, J. 2016. Yield and net return from alfalfa cultivars under irrigation in south. Canadian Journal of Plant Science. 96(2): 165-175.
Alam, M., Trooien, TP., Dumler, TJ. and Rogers, DH. 2002. Using subsurface drip irrigation for alfalfa. Journal of the American water resources association. 2002; 38(6): 1715-1721.
Alizadeh, A. 2015. Design of irrigation systems under pressure. The second volume. Publications of Imam Reza University. (In Persian).
Darrell, J., Bosch, L., powell, A. and Scott, W. 2013. Investment Returns from Three Sub-surface Micro irrigation Tubing Spacing. Agricultural Economics.
Elmaloglou, S. and E. Diamantopoulos. 2009. Simulation of soil water dynamics under subsurface drip irrigation from line sources. J. Agric. Water Management 96(11): 1587-1595.
Finger, L., Wang, J., Malano, H., Chen, D. and Morris, M. 2015. Productivity and water use of grazed subsurface drip irrigated perennial pasture in Australia. Irrigation Science. 33(2):141-152.
Gadami Firouzabadi, A. and Sidan, S. M. 2018. Investigation of irrigation water efficiency and economic analysis of alfalfa crop production in rain and surface irrigation systems. Scientific Research Journal of Irrigation and Water Engineering of Iran. No. 37. pp. 149-136. (In Persian).
Gharib, M, and Hosseini, A. 2018. Investigation of ambrothermic curves in the interpretation of drought phenomenon (case study in Semnan Province). The 5th National Conference of Watershed Sciences and Engineering of Iran. Gorgan University of Agricultural Sciences and Natural Resources. (In Persian).
Hengeller, J. 1995. Use of drip irrigation on alfalfa. In Proc. of the Central Plains Irrigation Short course, Feb. 7-8, 1995, Garden City, Kansas. Kansas State Univ. Extension Biol. And Agric. Engr. Dept., Manhattan, KS. pp. 160-167.
Hutmacher, R.B., Davis, K.R., Schoneman, R.A., Vail, S.S. and Mead, R.M. 1996. Subsurface drip irrigation of row crops: a review of 15 years of research at the Water Management. Agric. Water Manage.42, 1–27.
Kandelous, MM., Kamai, T., Vrugt, JA., Hanson, B., and Hopmans, JW. 2012. Evaluation of subsurface drip irrigation design and management parameters for alfalfa. Agricultural Water Management. 109 (9): 81-93.
Kazumba, S., Gillerman, L., Demalach, Y. and Oron, G. 2010. Sustainable domestic effluent reuse via subsurface drip irrigation (SDI): alfalfa as a perennial model crop. Water Science & Technology A Journal of the International Association on Water Pollution Research. 61(61): 625-632.
Lamm, F.R., Ayars, J.E. and Nakayama, F.S. 2007. Micro irrigation for Crop Production –Design, Operation, and Management. Elsevier, Amsterdam, pp. 618.
Lamm, F.R. 2016. Subsurface drip irrigation and possibilities in alfalfa. Proceedings, California Alfalfa and Forage Symposium, November, Reno, Nevada.
Mahbub, A., Trooien, T. P., Dumler, T. J. and Danny, Rogers. 2002. Using subsurface drip irrigation for alfalfa. Journal of the American Water Resources Association. 38(6), 1715- 1721.
Malareza Gassab, F., Abdshahi, A. and Marzban, A. 2019. Determining the physical and economic water productivity (case study of Dezful city). Journal of Agricultural Economics Research. Vol 12, No. 3. pp. 42-79. (In Persian).
Mousavi, S. M., Mirlatifi, S. M. and Tabatabaei S. H. 2014. The effect of the depth and distance of installing subsurface irrigation pipes on the growth of grass under the conditions of using urban wastewater. Journal of Agricultural Sciences and Techniques, Water and Soil Sciences. No. 72. pp. 138-129. (In Persian).
Santos, LNS., Goncalves, IZ., Barbosa, EAA., Tuta, NF., Feitosa, D. and Pires, R. 2014. Subsurface irrigation quality at two depths of placement of drip tapes. Vii Congreso Iberico De Agroingenieria Y Ciencias Horticolas: Innovar Y Producir Para El Futuro. Innovating and Producing for the Future. 1134-1138
Shufang, W., Xiyun, J., Weihua, G., Jian, L., Yungang, B. and Liping, W. 2018. Adaptability of shallow subsurface drip irrigation of alfalfa in an arid desert area of Northern Xinjiang. PLoS ONE 13(4): e0195965.
Shahnavazi, A. 2019. Investigating the profitability of alfalfa cultivation, according to the humidity index in Iran. Fodder and animal feed promotional magazine. Vol 1, No 2. pp 42-33. (In Persian).Van Halsema, G.E., and Vincent, L. 2012. Efficiency and productivity terms for water management: A matter of contextual relativism versus general absolutism. Agricultural Water Management, 108: 9-15.
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