Harvard Forest; long wavelength; microwave radiometry; plant water potential; Soil plant atmosphere system; vegetation transmissivity; Forest stand; Harvard forests; Long wavelength; Microwave radiometry; Plant water potential; Transmissivity; Vegetation optical depth; Vegetation transmissivity; Water potential; Computer Science Applications; Earth and Planetary Sciences (all)
Abstract :
[en] A retrieval methodology for forest water potential from ground-based L-band radiometry is proposed. It contains the estimation of the gravimetric and the relative water content of a forest stand and tests in situ- and model-based functions to transform these estimates into forest water potential. The retrieval is based on vegetation optical depth data from a tower-based experiment of the SMAPVEX 19-21 campaign for the period from April to October 2019 at Harvard Forest, MA, USA. In addition, comparison and validation with in situ measurements on leaf and xylem water potential as well as on leaf wetness and complex permittivity are foreseen to understand limitations and potentials of the proposed approach. As a first result the radiometer-based water potential estimates of the forest stand are concurrent in time and similar in value with their in situ (xylem) counterparts from single trees in the radiometer footprint.
Jagdhuber, T.; German Aerospace Center, Microwaves and Radar Institute, Wessling, Germany ; University of Augsburg, Institute of Geography, Augsburg, Germany
Fluhrer, A.; German Aerospace Center, Microwaves and Radar Institute, Wessling, Germany ; University of Augsburg, Institute of Geography, Augsburg, Germany
Schmidt, A.-S.; German Aerospace Center, Microwaves and Radar Institute, Wessling, Germany ; University of Augsburg, Institute of Geography, Augsburg, Germany
Jonard, François ; Université de Liège - ULiège > Département de géographie ; Agrosphere (IBG-3), Institute of Bio- and Geosciences, Forschungszentrum Jülich GmbH, Jülich, Germany ; Earth and Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
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