Effect of changing vegetation and precipitation on denudation – Part 2: Predicted landscape response to transient climate and vegetation cover over millennial to million-year timescales
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Published:2018-10-08
Issue:4
Volume:6
Page:859-881
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ISSN:2196-632X
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Container-title:Earth Surface Dynamics
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language:en
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Short-container-title:Earth Surf. Dynam.
Author:
Schmid Manuel, Ehlers Todd A.ORCID, Werner ChristianORCID, Hickler Thomas, Fuentes-Espoz Juan-Pablo
Abstract
Abstract. We present a numerical modeling investigation into the
interactions between transient climate and vegetation cover with hillslope
and detachment limited fluvial processes. Model simulations were designed to
investigate topographic patterns and behavior resulting from changing climate
and the associated changes in surface vegetation cover. The Landlab surface
process model was modified to evaluate the effects of temporal variations in
vegetation cover on hillslope diffusion and fluvial erosion. A suite of
simulations were conducted to represent present-day climatic conditions and
satellite derived vegetation cover at four different research areas in the
Chilean Coastal Cordillera. These simulations included steady-state
simulations as well as transient simulations with forcings in either climate
or vegetation cover over millennial to million-year timescales. Two different
transient variations in climate and
vegetation cover including a step change in climate or vegetation were used, as well as
100 kyr oscillations over 5 Myr. We conducted eight different step-change
simulations for positive and negative perturbations in either vegetation
cover or climate and six simulations with oscillating transient forcings for
either vegetation cover, climate, or oscillations in both vegetation cover
and climate. Results indicate that the coupled influence of surface
vegetation cover and mean annual precipitation shifts basin landforms towards
a new steady state, with the magnitude of the change being highly sensitive to the
initial vegetation and climate conditions of the basin. Dry, non-vegetated
basins show higher magnitudes of adjustment than basins that are situated in
wetter conditions with higher vegetation cover. For coupled conditions when
surface vegetation cover and mean annual precipitation change simultaneously,
the landscape response tends to be weaker. When vegetation cover and mean
annual precipitation change independently from one another, higher magnitude
shifts in topographic metrics are predicted. Changes in vegetation cover show
a higher impact on topography for low initial surface cover values; however,
for areas with high initial surface cover, the effect of changes in
precipitation dominate the formation of landscapes. This study demonstrates
the sensitivity of catchment characteristics to different transient forcings in
vegetation cover and mean annual precipitation, with
initial vegetation and climate conditions playing a crucial role.
Funder
Deutsche Forschungsgemeinschaft
Publisher
Copernicus GmbH
Subject
Earth-Surface Processes,Geophysics
Reference67 articles.
1. Acosta, V. T., Schildgen, T. F., Clarke, B. A., Scherler, D., Bookhagen, B.,
Wittmann, H., von Blanckenburg, F., and Strecker, M. R.: Effect of vegetation
cover on millennial-scale landscape denudation rates in East Africa,
Lithosphere, 7, 408–420, https://doi.org/10.1130/L402.1, 2015. 2. Alberts, E. E., Nearing, M. A., Weltz, M. A., Risse, L. M., Pierson, F. B.,
Zhang, X. C., Laflen, J. M., and Simanton, J. R.: Soil component, chap. 7,
in: USDA Water Erosion Prediction Project Hillslope Profile and Watershed
Model Documentation, edited by: Flanagan D. C. and Nearing M. A., NSERL
Report No. 10. USDA-ARS National Soil Erosion Research Laboratory, West
Lafayette, Ind., USA, 47 pp., 1995. 3. Allen, C. D. and Breshears, D. D.: Drought-induced shift of a
forest–woodland ecotone: rapid landscape response to climate variation, P.
Natl. Acad. Sci. USA, 95, 14839–14842, 1998. 4. Allen, C. D., Macalady, A. K., Chenchouni, H., Bachelet, D., McDowell, N.,
Vennetier, M., Kitzberger, T., Rigling, A., Breshears, D. D., Hogg, E. H.
(Ted), Gonzalez, P., Fensham, R., Zhang, Z., Castro, J., Demidova, N., Lim,
J.-H., Allard, G., Running, S. W., Semerci, A., and Cobb, N.: A global
overview of drought and heat-induced tree mortality reveals emerging climate
change risks for forests, Forest Ecol. Manag., 259, 660–684,
https://doi.org/10.1016/j.foreco.2009.09.001, 2010. 5. Amundson, R., Heimsath, A., Owen, J., Yoo, K., and Dietrich, W. E.: Hillslope
soils and vegetation, Geomorphology, 234, 122–132,
https://doi.org/10.1016/j.geomorph.2014.12.031, 2015.
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