Dripper Uniformity
This page contains links to the dripper uniformity online calculator (above) as well as information about Dripper Uniformity generally and links to further reading.
Increasing pressure is being placed on water resources due to the current extensive drought and low water allocations. This has caused a shift to pressurised irrigated systems throughout Australia. Drip irrigation has been increasing as the key components for its success converge i.e. systems designed to a high standard specifically for Australian farming conditions, cost/ha decline as more equipment is made in Australia, costs worldwide become more competitive, management skills increase, and well developed business plans evolve that ensure return on investment.
Essential to getting the high returns required is that the system performs to provide high levels of distribution uniformity to maximise uniformity of crop and more efficient use of water and fertiliser. In commercial situations, field evaluations of drip irrigation systems are often overlooked with many growers taking for granted that their system is behaving according to the design specification. Drip irrigation systems theoretically have high distribution uniformities and application efficiencies, however in commercial field systems these theoretical efficiencies can be difficult to achieve.
Recent work in vineyards in the Murrumbidgee Irrigation Area, funded through the Grape and Wine Research and Development Corporation's (GWRDC) 'Soil and Water Initiative' and the CRC for Irrigation Futures 'Toolkits for Profitability and Longevity programme', has provided some interesting data on drip irrigation system application rate variability, and its effect on vine performance in terms of yield and quality parameters in irrigated vineyards.
Often application rates have the potential to vary over an irrigation unit due to poor design or management factors. Research and development through these projects is now being used to develop online tools for helping irrigators measure and understand the effects of drip distribution uniformity on crop production and how to manage it. At present an online assessment portal is being developed which helps irrigations firstly identify potential distribution uniformity issues through satellite Normalised Difference Vegetation Indexes (NDVI) and provides direction on how to sample irrigation units. An automatic online report generation facility at this site then provides irrigators with maps of the dripper application rates across the field, seasonal applied irrigation water maps over the field, seasonal applied fertigation maps such as nitrogen applied across the field and calculates the irrigation system distribution uniformity for their field.
Further Reading
Hornbuckle, J., Smith, D., Lanyon, D., Goodwin, I., McClymont, L., Zandona, R., and Christen, E. (2007). Drip Irrigation Variability - how well is your vineyard drip system performing? Irrigation Research and Extension Committee (IREC) Farmers Newsletter, 176. http://www.irec.org.au/farmer_f/pdf_176/Drip%20irrigation%20variability.pdf
Hornbuckle, J.W., Christen, E.W., Smith, D.J., McClymont, L., Goodwin, I. & Lanyon, D.M. (2006) Measuring drip irrigation distribution uniformity in irrigated vineyards and understanding its effects on vine vigour, Australian Society of Viticulture and Oenology, Water Friend or For? Proceedings ASVO Seminar, Mildura Arts Centre, Mildura, South Australia, Friday 2 November 2007, ISBN 0 9775256 27 https://www.asvo.com.au/proceedings/?action=view&id=29