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Titel |
Livestock redistribute runoff and sediments in semi-arid rangeland areas |
VerfasserIn |
P. Sarah, M. Zonana |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1869-9510
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Digitales Dokument |
URL |
Erschienen |
In: Solid Earth ; 6, no. 2 ; Nr. 6, no. 2 (2015-04-29), S.433-443 |
Datensatznummer |
250115442
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Publikation (Nr.) |
copernicus.org/se-6-433-2015.pdf |
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Zusammenfassung |
Semi-arid areas where grazing is the main land use exhibit a
"three-phase-mosaic" pattern of dominant surface patches: shrubs, trampling
routes, and intershrub areas. This pattern differs from the "two-phase
mosaic" seen in grazing-free semi-arid areas. The patches might create a
positive feedback process in which enhanced infiltration beneath shrubs
minimizes overland flow from under their canopies, thereby strengthening the
sink–source mechanism by which overland flow generated between shrubs
rapidly infiltrates into the soil beneath them, where it deposits soil
particles, litter, nutrients and organic matter, thereby enhancing
infiltration by changing the local microtopography, and improving soil
properties. To analyze sink–source relationships among the patches in grazed
areas in rangelands of the semi-arid northern Negev region of Israel, we
constructed small runoff plots, 0.25–1.0 m2 in area, of five types:
shrub (Sarcopoterium spinosum), intershrub, route, route–shrub combination, and
intershrub–shrub combination. The shrubs always occupied the downslope part
of the plot. Overland flow and sediment deposits were measured in all plots
during 2007/8 and 2008/9. The combined plots yielded much less overland flow
and sediments than intershrub, routes and shrub ones, indicating that the
shrubs absorbed almost all the yields of the upper part of their plots. The
shrubs generated less runoff and sediments than routes and intershrubs;
runoff flows from the routes and intershrubs were similar; sediment yield
was highest in the intershrubs. Thus, runoff yield exhibited a two-phase
mosaic pattern, and sediment yield, i.e., soil erosion, a three-phase mosaic
pattern. |
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