It appeared that growers were in need of a more simple and cheaper concept of the earlier developed lysimeter with automatic volumetric drain meter. To cope with the demand, a so called ‘light’ version of the lysimeter was developed, with measuring by hand. Furthermore a survey was done to alternatives for the soil moisture sensors used so far. Unfortunately, no sensors were found which could meet all requirements for soil grown greenhouse crops.
The tools developed, i.e. lysimeter, drainage meter, sensors and models will support the decisions made by growers for irrigation and fertilisation aiming at reduction in water-bound emissions from soil grown greenhouse crops. Growers that used the tools in an active way, reduced the leaching of nutrients drastically. The interpretation of soil moisture sensors is still complex due to big differences in soil type and crop management decisions.
The results of water balance calculations at the growers show that the estimations of the crop transpiration by the model can be matched with the data from the lysimeter by using a crop specific calibration factor.Report by:
Wim Voogt, Jos Balendonck, Marius Heinen (Wageningen UR Alterra), Frank van der Helm,Jan Janse, Gert-Jan Swinkels
Research sponsored by: Productschap Tuinbouw