Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1029/2017WR021719
Licence creative commons licence
Title (Primary) Cosmic‐ray neutron rover surveys of field soil moisture and the influence of roads
Author Schrön, M.; Rosolem, R.; Köhli, M.; Piussi, L.; Schröter, I.; Iwema, J.; Kögler, S.; Oswald, S.E.; Wollschläger, U.; Samaniego, L. ORCID logo ; Dietrich, P. ORCID logo ; Zacharias, S. ORCID logo
Source Titel Water Resources Research
Year 2018
Department CHS; MET; BOSYS
Volume 54
Issue 9
Page From 6441
Page To 6459
Language englisch
Keywords road effect; field‐scale; soil moisture; cosmic‐ray neutrons; mobile survey; COSMOS rover
Abstract Measurements of root‐zone soil moisture across spatial scales of tens to thousands of meters have been a challenge for many decades. The mobile application of Cosmic‐Ray Neutron Sensing (CRNS) is a promising approach to measure field soil moisture non‐invasively by surveying large regions with a ground‐based vehicle. Recently, concerns have been raised about a potentially biasing influence of local structures and roads. We employed neutron transport simulations and dedicated experiments to quantify the influence of different road types on the CRNS measurement. We found that roads introduce a substantial bias in the CRNS estimation of field soil moisture compared to off‐road scenarios. However, this effect becomes insignificant at distances beyond a few meters from the road. Measurements on the road could overestimate the field value by up to 40% depending on road material, width, and the surrounding field water content. The bias could be largely removed with an analytical correction function that accounts for these parameters. Additionally, an empirical approach is proposed that can be used without prior knowledge of field soil moisture. Tests at different study sites demonstrated good agreement between road‐effect corrected measurements and field soil moisture observations. However, if knowledge about the road characteristics is missing, measurements on the road could substantially reduce the accuracy of this method. Our results constitute a practical advancement of the mobile CRNS methodology, which is important for providing unbiased estimates of field‐scale soil moisture to support applications in hydrology, remote sensing, and agriculture.
Persistent UFZ Identifier
Schrön, M., Rosolem, R., Köhli, M., Piussi, L., Schröter, I., Iwema, J., Kögler, S., Oswald, S.E., Wollschläger, U., Samaniego, L., Dietrich, P., Zacharias, S. (2018):
Cosmic‐ray neutron rover surveys of field soil moisture and the influence of roads
Water Resour. Res. 54 (9), 6441 - 6459 10.1029/2017WR021719