Session 13. Subsurface Drip Irrigation II
The Sustainability and Potential of Subsurface Drip Irrigation
Claude J. Phene
After nearly three decades of research and development, subsurface drip irrigation (SDI) has evolved into an irrigation method with high potential for efficient and economical productivity. Research has almost entirely solved the original problems of root intrusion, plugging, fertility management and lateral installation. Results obtained have shown large increases in water and nitrogen use efficiencies with concurrent increases in crop yield and quality. Prevention of groundwater contamination with nitrates and salts and long-term economic sustainability have also been demonstrated. Because SDI is installed below the soil surface, a properly-managed system can increase the advantages of surface drip irrigation, especially in the areas of water and nutrient conservation, salinity management, deep percolation, manageability and long-term sustainability. This is partially due to differences in wetted soil volume and areas which are larger for the SDI system (spherical volume) than for the surface drip system (hemispherical volume) for the same emitter configuration and discharge rate. As a total management system, SDI offers the most productive, efficient and sustainable alternative to any other irrigation method.
Keywords: Water, water-use efficiency, uniformity, water quality, environment, roots, sustainability, salinity
Abstract taken from paper found on pages 359 to 367 in Proceedings of 5th International Microirrigation Congress, April 2-6, 1995, Orlando, Florida. American Society of Agricultural Engineers, 2950 Niles Road, St. Joseph, Michigan 49085-9659, USA. Phone: 616-429-0300 FAX: 616-429-3852 EMAIL: HQ@ASAE.ORG
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Subsurface Microirrigation Management and Lateral Spacing for Cotton in the Southeastern USA
C. R. Camp, P. G. Hunt, and P. J. Bauer
Cotton yields for two microirrigation lateral placements (spacings) and three nitrogen sidedness methods were compared with rainfall-only treatments during the 1991-1993 growing seasons. In 1992 and 1993 cotton yield for both in-row and alternate-furrow microirrigation lateral placements was higher than for rainfall-only treatments. Yields were similar for the two lateral spacings. The wider spacing in the alternate-furrow placement should reduce irrigation system cost by about 30 percent. Yields were similar among N application methods despite one having about 30 percent less N applied. The wider lateral spacing and lower N rate could significantly reduce the cost of cotton production with microirrigation, and make this technology more attractive to cotton growers. The ability to apply N as needed via the irrigation system could reduce nitrogen fertilizer rates, thus reducing the potential for ground water contamination.
Keywords: Lateral placement, Trickle irrigation, Tensiometers, Nitrate, Computer simulation
Abstract taken from paper found on pages 368 to 374 in Proceedings of 5th International Microirrigation Congress, April 2-6, 1995, Orlando, Florida. American Society of Agricultural Engineers, 2950 Niles Road, St. Joseph, Michigan 49085-9659, USA. Phone: 616-429-0300 FAX: 616-429-3852 EMAIL: HQ@ASAE.ORG
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Subsurface and Surface Microirrigation of Corn--U.S. Southern High Plains
T. A. Howell, A. D. Schneider, and B. A. Stewart
Microirrigation has the potential to minimize application losses from droplet evaporation and drift from sprinklers, improve irrigation control with smaller, frequent applications, supply nutrients to the crop as needed, minimize deep percolation, and improve crop yields. This study was conducted to evaluate subsurface and surface microirrigation application methods on crop performance. The effects of irrigation frequency, amount, and application method on crop yield, yield components, water use, and water use efficiency of corn (Zea mays L.) were investigated in 1993 at Bushland, TX, on a slowly permeable soil [Pullman clay loam (fine, mixed, thermic Torrertic Paleustoll)] in a semi-arid environment. Irrigation frequencies were once a day and once a week; irrigation levels varied from dryland (no post emergence irrigation) to full crop water use replenishment; and application methods were on the soil surface and below ground (0.3 m) with emitters spaced 0.45 m apart and drip lines spaced 1.5 m apart. In 1993, irrigation frequency and application method did not affect crop yields; however, severe deficit irrigation (33% of full irrigation) affected crop yields by reducing the seed mass and the seed number. On the clay loam soil at Bushland, irrigation frequency and application method are less critical than proper irrigation management to avoid water deficits that affect crop yield for microirrigation systems.
Keywords: Irrigation management, water use, water use efficiency, yield, yield components
Abstract taken from paper found on pages 375 to 381 in Proceedings of 5th International Microirrigation Congress, April 2-6, 1995, Orlando, Florida. American Society of Agricultural Engineers, 2950 Niles Road, St. Joseph, Michigan 49085-9659, USA. Phone: 616-429-0300 FAX: 616-429-3852 EMAIL: HQ@ASAE.ORG
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Subsurface Dripline Spacing and Plant Population for Corn Production
H. L. Manges, W. E. Spurgeon, Z. M. Huang, D. J. Tomsicek
Irrigation is experiencing increased competition for water from municipalities and industry. Conversion of gravity and sprinkler systems to subsurface drip systems could lead to sustained irrigation in areas with diminishing water supplies. Installation cost of subsurface drip systems is highly dependent on dripline spacing. Prediction equations were developed to estimate plant population for maximum grain yield at various dripline spacings, as well as grain yield as a function of plant population, dripline spacing, and growing season precipitation. The prediction equations can be used to determine the most economical dripline spacing on silt loam soil in Southwest Kansas and areas of similar climate. They apply when corn rows are run perpendicular to the drip lines and dripline spacing is 0.76 to 3.05 m, the range used in the field study.
Keywords: Irrigation, Subsurface drip, Dripline spacing, Corn, Plant population
Abstract taken from paper found on pages 382 to 387 in Proceedings of 5th International Microirrigation Congress, April 2-6, 1995, Orlando, Florida. American Society of Agricultural Engineers, 2950 Niles Road, St. Joseph, Michigan 49085-9659, USA. Phone: 616-429-0300 FAX: 616-429-3852 EMAIL: HQ@ASAE.ORG
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Corn Production Using Subsurface Drip Irrigation
F. R. Lamm, W. E. Spurgeon, D. H. Rogers and H. L. Manges
Studies were initiated in 1989 at Kansas State University (KSU) to develop the methodology for successful application of subsurface drip irrigation (SDI) for corn production on the deep silt loam soils of western Kansas. Research efforts included evaluation of: the water requirement of subsurface drip-irrigated corn; the effect of SDI application frequency; irrigation uniformity for various length driplines: optimum dripline spacing and nitrogen management for subsurface drip-irrigated corn. SDI for row crops in the Central Great Plains is an emerging, but sound technology. Changing economic and environmental factors and/or resource constraints could result in increased adoption of this technology.
Keywords: Water use efficiency, system design, irrigation frequency, fertigation
Abstract taken from paper found on pages 388 to 394 in Proceedings of 5th International Microirrigation Congress, April 2-6, 1995, Orlando, Florida. American Society of Agricultural Engineers, 2950 Niles Road, St. Joseph, Michigan 49085-9659, USA. Phone: 616-429-0300 FAX: 616-429-3852 EMAIL: HQ@ASAE.ORG
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Subsurface Drip Irrigation (SDI) for Field Corn - An Economic Analysis
K. C. Dhuyvetter, F. R. Lamm, D. H. Rogers
An economic analysis was conducted to examine the feasibility of subsurface drip irrigation (SDI) for corn production in western Kansas. The analysis revealed that SDI systems had lower returns than in-canopy center pivot sprinkler systems. Economic returns were relatively insensitive to typical pumping costs and application efficiencies, but were very sensitive to initial investment, system longevity, and corn yield.
Keywords: Microirrigation, partial budgeting, investment costs, system longevity
Abstract taken from paper found on pages 395 to 401 in Proceedings of 5th International Microirrigation Congress, April 2-6, 1995, Orlando, Florida. American Society of Agricultural Engineers, 2950 Niles Road, St. Joseph, Michigan 49085-9659, USA. Phone: 616-429-0300 FAX: 616-429-3852 EMAIL: HQ@ASAE.ORG
