1. Institut für Agrartechnologie und Biosystemtechnik Possibilities of using the drip irrigation laterals on centre pivot irrigation machines Jano Anter, Dr. Heinz Sourell, Hans-Heinrich Thörmann, Federal Research Institute for Rural Areas, Forestry and Fisheries, Germany Institute of Agricultural Technology and Biosystems Engineering 27 June 2012, Adelaide German National Committee of ICID (GECID)

2. 2 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell

3. 3 Contents Irrigation in Germany Advantages & disadvantages of drip irrigation and center pivot Steps to mobile drip irrigation Technical aspects Costs analysis Summary

4. 4 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Irrigation in Germany 3% of the agricultural land are irrigated in Germany Humid climate, dry periods, sandy soils Cultures worth of irrigation: i.e. Potatos, Sugar beets Use of modern irrigation techniques The techniques are developed in terms of claims by farmers: - Water distrubtion - Intensity of labour - Water-efficient - Energy consumption

5. 5 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Water distribution-systems

6. 6 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Advantages & disadvantages of drip irrigation +  High water use efficiency  Low water losses  Low energy requirements  Possibility of chemigation -  High total costs  High labour requirements for the assembly and disassembly

7. 7 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Advantages & disadvantages of center pivot with sprinkler +  Full-Automatic machine management  Low labour requirements  Moderate capital requirement  Simple to use -  Water losses  Wind drift  High energy requirements

8. 8 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Operating costs Center Pivot Drip Irrigation

9. 9 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Steps to mobile drip irrigation Drip irrigation Center pivot Mobile Drip Irrigation

10. 10 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Installation of mobile drip irrigation by centre pivot

11. 11 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Field experiments  The Center pivot consisting 9 towers  The total lenght of this pivot machine was approximately 428 m  The total irrigated area of about 57 ha  Drip tubes distance: 0.75 m  In the field investigations, two operating pressures were used at the inlet of the drip tubes (50 kPa and 100 kPa)

12. 12 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Emitters Mobile drip irrigation needs emitters that have: High discharge (8 l/h & 10 l/h) Low distance between them (0.15 m) To reduce the lenght of drip tubes and the numbers of emitters High emission uniformity (over 95 %) Low coefficient of variation (lower than 5 %) To enhance irrigation water distrubtion on the soil surface

13. 13 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Length of drip tubes at two pressures -The lenght of the drip tubes is dependent upon the emitter discharge and the distance from the pivot point -The lenght of the drip tubes increases as the distance from the pivot point grows -For the stability of the centre pivot irrigator, additional friction force is important -The friction force at 50 kPa were higher than the friction force at 100 kPa (2470 N & 1743 N at the ninth tower) -This force is suitable for the electric motors which are mounted on each tower.

14. 14 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Length of drip tubes at two pressures

15. 15 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Costs analysis (Capital requirement)

16. 16 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Costs analysis (Operating costs)

17. 17 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Summary High water efficiency / Water saving up to 20% Energy conservation up to 40% The total costs of MDI were close to the total costs of a CP For the same area we need only 1,6 % respectively of the tubes that would needed for a SDI Filtering of the water can become important Further experiments with other plants is necessary

18. 18 Jano Anter, Hans-Heinrich Thörmann, Dr. Heinz Sourell Many thanks for your attention!