ISHS Acta Horticulturae 664: IV International Symposium on Irrigation of Horticultural Crops
TENSIOMETRIC MEASUREMENTS: A TOOL TO ANALYSE ROOT GROWTH AND TO SCHEDULE IRRIGATION OF LANDSCAPE TREES |
| Authors: | C. Isbérie, A. Bensaoud, E. Lesage, C. Lohou |
| Keywords: | soil water, irrigation scheduling, walnut (Juglans nigra), urban soil, tree transplantation, drain irrigation |
| Abstract:
In agriculture, there are strategies for scheduling irrigation using tensiometric sensors. These strategies have been developed over more than 20 years, experimentally verified, tested and put into agricultural practice. The problem of irrigation in landscaped areas is unlike that of agriculture: urban soils are often thin layers of reconstituted soil. Their role as a water reservoir is further reduced even more by the fact that their physical and chemical fertility is altered. Over the past ten years, efforts have been made to understand how soil water works in anthroposoils in urban environments. The special case of transplanted plants, such as trees, is accentuated by their insufficient root absorption capacity: a tree transplanted into an urban environment suffers an imbalance between its weak root absorption capacity and transpiration, since it loses nearly 70% of its root system when it is dug up at the nursery. For a period of four years experimentation was carried out to follow root growth of walnut trees (Juglans nigra) with three irrigation procedures: a distance of 0.45 m or of 1.25 m between the drain pipe used as irrigation emitter and the tree trunk with systematic irrigation at regular time intervals, or a distance of 1.25 m and tensiometric scheduling. Tensiometric measurements were a good indicator of root growth, so it might be possible to include tensiometric monitoring as a technical requirement in a contract. Moreover, when used as scheduling tools, tensiometric measurements allowed large savings in irrigation water. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
