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- Bärring, Lars, et al.
(författare)
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Wind erosion on arable land in Scania, Sweden and the relation to the wind climate - a review
- 2003
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Ingår i: Catena. - 0341-8162. ; 52:3-4, s. 173-190
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Tidskriftsartikel (refereegranskat)abstract
- This paper addresses variations in the wind climate in relation to changes in the impact of wind erosion on agricultural lands with Scania, the southernmost province of Sweden, as an example. The literature concerning wind erosion in the region is reviewed and the conclusions are linked to recent analyses of the regional wind climate. Presently, wind erosion occasionally induces problems in light soil areas of the intensively cultivated Scania. It is not a new phenomenon that results from modem farming practice; it was documented already in the 18th century. This was an era of major land use changes because the increasing population required new and more vulnerable areas to be cultivated, which resulted in an ecological crisis due to increased wind erosion. Partly overlapping in time, a series of land amalgamation reforms transformed the land-use resulting in larger fields. Analyses of the frequency of wind directions indicate that variations in the large-scale wind climate occurred at that time. Wind erosion again became a topic of concern in the 20th century. Extensive analyses of several aspects of the wind climate (e.g., storminess and cyclone intensity) of Scandinavia and northwestern Europe show that there have been interdecadal variations but no sign of an overall long-term trend. The recurring periods of intensified wind erosion problems can best be explained as the combined result of a varying wind climate and the lack of appropriate long-term maintenance strategies for protective measures through the intervening periods of benign wind climate. (C) 2003 Elsevier Science B.V. All rights reserved.
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| 2. |
- Hamed Abd El Mageed, Yasser, et al.
(författare)
-
Comparison between rainfall simulator erosion and observed reservoir sedimentation in an erosion-sensitive semiarid catchment
- 2002
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Ingår i: Catena. - 0341-8162. ; 50:1, s. 1-16
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Tidskriftsartikel (refereegranskat)abstract
- Estimating catchment scale soil loss based on rainfall simulators is often hampered by the difficulty to scale up simulator results. Our objective was to develop and test a method for estimating catchment scale soil loss based on observed rainfall using a variable intensity rainfall simulator in an erosion-sensitive catchment in semiarid Tunisia. A 7-year period, 1992-1999, with observed sedimentation amounts in a downstream reservoir was chosen to test a methodology. The methodology was based on (1) energy adjustment for the used simulator due to the difference in kinetic energy of simulated and natural rainfall at equal intensities and (2) upscaling of simulated erosion in which rill erosion was estimated by adjusting the difference between slope lengths for the plots versus the catchment after onset of runoff. The comparison between calculated soil loss from rainfall simulator experiments and observed sedimentation in the downstream reservoir displayed good overall results. Calculated soil loss was found to be about 96%, 36%, and 80% for different observed subperiods, respectively. The observed low value for the second period was probably due an exceptionally intense rainfall event during this period, which appears to have led to gully erosion, soil slide, and riverbank collapse. Therefore, during this event, siltation in the reservoir may essentially be due to unaccounted erosion processes such as gully erosion. Overall, however, it appears that plot-scale variable intensity rainfall simulators can rather successfully estimate catchment scale soil losses. (C) 2002 Elsevier Science B.V. All rights reserved.
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