|
Read Full Article (file size: 1716756 bytes) Cited by
WATER RESOURCES RESEARCH,
VOL. 38, NO. 12,
1269,
doi:10.1029/2001WR000872,
2002
The role of bedrock topography on subsurface storm flow
Jim Freer
Department of Environmental Sciences, IENS,
University of Lancaster,
Lancaster,
UK
J. J. McDonnell
Department of Forest Engineering,
Oregon State University,
Corvallis,
Oregon,
USA
K. J. Beven
Department of Environmental Sciences, IENS,
University of Lancaster,
Lancaster,
UK
N. E. Peters
U.S. Geological Survey,
Atlanta,
Georgia,
USA
D. A. Burns
Department of Environmental Sciences, IENS,
University of Lancaster,
Lancaster,
UK
R. P. Hooper
U.S. Geological Survey,
Atlanta,
Georgia,
USA
B. Aulenbach
U.S. Geological Survey,
Atlanta,
Georgia,
USA
C. Kendall
U.S. Geological Survey,
Menlo Park,
California,
USA
Abstract
We conducted a detailed study of subsurface flow and water table response coupled with digital terrain analysis (DTA) of surface
and subsurface features at the hillslope scale in Panola Mountain Research Watershed (PMRW), Georgia. Subsurface storm flow
contributions of macropore and matrix flow in different sections along an artificial trench face were highly variable in terms
of timing, peak flow, recession characteristics, and total flow volume. The trench flow characteristics showed linkages with
the spatial tensiometer response defining water table development upslope. DTA of the ground surface did not capture the observed
spatial patterns of trench flow or tensiometric response. However, bedrock surface topographic indices significantly improved
the estimation of spatial variation of flow at the trench. Point-scale tensiometric data were also more highly correlated
with the bedrock surface-based indices. These relationships were further assessed for temporal changes throughout a rainstorm.
Linkages between the bedrock indices and the trench flow and spatial water table responses improved during the wetter periods
of the rainstorm, when the hillslope became more hydrologically connected. Our results clearly demonstrate that in developing
a conceptual framework for understanding the mechanisms of runoff generation, local bedrock topography may be highly significant
at the hillslope scale in some catchments where the bedrock surface acts as a relatively impermeable boundary.
Published 4
December
2002.
Index Terms: 1860 Hydrology: Runoff and streamflow; 1866 Hydrology: Soil moisture; 1824 Hydrology: Geomorphology (1625).
Read Full Article (file size: 1716756 bytes) Cited by
Citation: Freer, J., J. J. McDonnell, K. J. Beven, N. E. Peters, D. A. Burns, R. P. Hooper, B. Aulenbach, and C. Kendall
(2002),
The role of bedrock topography on subsurface storm flow,
Water Resour. Res.,
38(12),
1269,
doi:10.1029/2001WR000872.
Copyright 2002 by the American Geophysical Union.
|