Developing research methods and testing various conditions
The 12 root towers (each being 4 meters tall) are already in good use at Højbakkegård in Denmark, both in terms of developing isotope tracer methods and in order to test root development and use of resources during different environmental conditions, i.e. controlled conditions.
For example by placing a plastic roof over the towers, as illustrated in one of the photos, root development and resource uptake is analysed during different drought conditions. The roof help to control how much water the plants are having at their disposal.
Also, isotope water is injected at different soil depths and collecting transpiration water, illustrated by the plastic bags covering the plants in one photo, will provide data on water uptake at different depths. Additionally, nitrogen isotopes (15N) are injected into the soil and later the concentration of nitrogen in the leaves of the plants is tested. Thereby nitrogen uptake at different depths can be tested.