|
Titel |
Scale effect on overland flow connectivity at the plot scale |
VerfasserIn |
A. Peñuela, M. Javaux, C. L. Bielders |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1027-5606
|
Digitales Dokument |
URL |
Erschienen |
In: Hydrology and Earth System Sciences ; 17, no. 1 ; Nr. 17, no. 1 (2013-01-14), S.87-101 |
Datensatznummer |
250017677
|
Publikation (Nr.) |
copernicus.org/hess-17-87-2013.pdf |
|
|
|
Zusammenfassung |
A major challenge in present-day hydrological sciences is to enhance the
performance of existing distributed hydrological models through a better
description of subgrid processes, in particular the subgrid connectivity of
flow paths. The Relative Surface Connection (RSC) function was proposed by
Antoine et al. (2009) as a functional indicator of runoff flow connectivity.
For a given area, it expresses the percentage of the surface connected to
the outflow boundary (C) as a function of the degree of filling of the
depression storage. This function explicitly integrates the flow network at
the soil surface and hence provides essential information regarding the flow
paths' connectivity. It has been shown that this function could help improve
the modeling of the hydrograph at the square meter scale, yet it is unknown
how the scale affects the RSC function, and whether and how it can be
extrapolated to other scales. The main objective of this research is to
study the scale effect on overland flow connectivity (RSC function). For
this purpose, digital elevation data of a real field (9 × 3 m) and three
synthetic fields (6 × 6 m) with contrasting hydrological responses were
used, and the RSC function was calculated at different scales by changing
the length (l) or width (w) of the field. To different extents depending on
the microtopography, border effects were observed for the smaller scales
when decreasing l or w, which resulted in a strong decrease or increase of the
maximum depression storage, respectively. There was no scale effect on the
RSC function when changing w, but a remarkable scale effect was
observed in the RSC function when changing l. In general, for a given degree
of filling of the depression storage, C decreased as l increased, the change
in C being inversely proportional to the change in l. However, this observation applied
only up to approx. 50–70% (depending on the hydrological response of the
field) of filling of depression storage, after which no correlation was
found between C and l. The results of this study help identify the minimal
scale to study overland flow connectivity. At scales larger than the minimal
scale, the RSC function showed a great potential to be extrapolated to other
scales. |
|
|
Teil von |
|
|
|
|
|
|