Indoorlysimeter, English Page of the Federal Agency for Water Management

Indoorlysimeter

Lysimeters are an important instrument for measuring the soil water balance and for tracing water and material flows in the soil. In order to be able to evaluate the water flow in coarse sediments, which are often carriers of significant groundwater deposits, a cylinder with undisturbed gravel, in total 4 m high, was installed and instrumented in the Institute.

Contact Person: Andreas Scheidl

Brief Description:

Coarse sediments in valley and basin locations are often carriers of significant groundwater resources for drinking water supply. Sustainable management of such water stocks is therefore a top priority environmental objective. The assessment of vertical water flow, groundwater recharge and the associated solute transport through thick gravel bodies are associated with significant uncertainties.

In order to be prepared for future questions, two cylinders with undisturbed gravel (4 m high and with a diameter of 0.78 m) were taken from a gravel pit and instrumented. A total of 19 sensors for water content measurement, 11 temperature sensors and 21 tensiometers for suction stress measurement are installed.

Furthermore, two scales, which register the water inflow to the column and the water outflow from the column, respectively, are also integrated into the data acquisition. The measured values for all these sensors are recorded by means of a data logger.

A wide variety of experiments and investigations can now be carried out at this indoor lysimeter, which will help to support and validate the formulation of model approaches for solute transport in the near-groundwater zone.

The 4 m high cylinder mentioned in the text is shown schematically. 19 soil moisture probes (TDR probes) are placed at intervals between 10 and 30 cm. The 21 tensiometers and 11 sensors for measuring the temperature in the gravel body are also distributed over the height. At the very bottom is a steel trough in which the water is collected. Outside the cylinder, a thin standpipe runs parallel. The entire cylinder stands on a scale. In addition, there are 3 measuring probes that measure the air temperature in the room. On the left outside the cylinder are the indications in centimetres where which probes are mounted. — © Graphic: BAW-IKT / Scheidl

schematic representation