Soil moisture signatures provide a promising solution to overcome the
difficulty of evaluating soil moisture dynamics in hydrologic models.
Soil moisture signatures are metrics that quantify the dynamic aspects
of soil moisture timeseries and enable process-based model evaluations.
To date, soil moisture signatures have been tested only under limited
land-use types. In this study, we explore soil moisture signatures’
ability to discriminate different dynamics among contrasting land-uses.
We applied a set of nine soil moisture signatures to datasets from six
in-situ soil moisture networks worldwide. The dataset covered a range of
land-use types, including forested and deforested areas, shallow
groundwater areas, wetlands, urban areas, grazed areas, and cropland
areas. Our set of signatures characterized soil moisture dynamics at
three temporal scales: event, season, and a complete timeseries.
Statistical assessment of extracted signatures showed that (1)
event-based signatures can distinguish different dynamics for all the
land-uses, (2) season-based signatures can distinguish different
dynamics for some types of land-uses (deforested vs. forested, urban vs.
greenspace, and cropped vs. grazed vs. grassland contrasts), (3)
timeseries-based signatures can distinguish different dynamics for some
types of land-uses (deforested vs. forested, urban vs. greenspace,
shallow vs. deep groundwater, wetland vs. non-wetland, and cropped vs.
grazed vs. grassland contrasts). Further, we compared signature-based
process interpretations against literature knowledge; event-based and
timeseries-based signatures generally matched well with previous process
understandings from literature, but season-based signatures did not.
This study will be a useful guideline for understanding how
catchment-scale soil moisture dynamics in various land-uses can be
described using a standardized set of hydrologically relevant
metrics.