Publication Details

Category Text Publication
Reference Category Journals
DOI 10.3390/s22103887
Licence creative commons licence
Title (Primary) A phase-dependent effect that enables multi-scale moisture measurements in heterogeneous substrates using tubular RH sensors
Author Lazik, D.
Source Titel Sensors
Year 2022
Department BOSYS
Volume 22
Issue 10
Page From art. 3887
Language englisch
Topic T5 Future Landscapes
Keywords soil; fertility; soil litter; ignition risk; water saturation; heterogeneity; water sorption; membrane; sensor
Abstract A knowledge of the moisture in soils/soil litter allows for the estimation of irrigation needs or the risk of forest fire. A membrane-based humidity sensor (MHS) can measure the relative humidity (RH) as an average value in such heterogeneous substrates via its sensitive tubular silicone membrane. This RH corresponds to the moisture-dependent water potential of the substrate. For humid conditions in soil, however, the RH is already larger than 98% and hence is insensitively correlated with the water potential. For such conditions, a step-like response of the MHS was found, which occurs if the silicone membrane is wetted with water. This appears to correspond to oversaturated water vapor and must be attributed to a phase-dependent sorption mechanism of the membrane. This effect allows the expansion of the range of applications of the MHS in the detection of liquid water, such as in dew point detection. Based on this, the dependency of the measurement signal on the mean water saturation in a substrate along the tubular membrane is demonstrated. A comparison of the measurement signal with an internal reference signal according to the MHS measurement principle makes it possible to distinguish this new, saturation-dependent measurement scale from the one used for RH measurement.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=26160
Lazik, D. (2022):
A phase-dependent effect that enables multi-scale moisture measurements in heterogeneous substrates using tubular RH sensors
Sensors 22 (10), art. 3887 10.3390/s22103887