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| Titel |
Monitoring soil erosion in terraced catchments in Mediterranean regions: a
field experiment in Cyprus |
| VerfasserIn |
Corrado Camera, Hakan Djuma, Christos Zoumides, Marinos Eliades, Adriana Bruggeman, Dante Abate, Marina Faka, Sorin Hermon |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250121780
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| Publikation (Nr.) |
 EGU/EGU2016-627.pdf |
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| Zusammenfassung |
| Terraces retained by dry-stone walls are very common features in mountainous
Mediterranean environments. These structures provide accessible agricultural land on steep
slopes, favoring water infiltration and reducing water runoff and soil erosion. However,
during the last decades, an increasing trend of agricultural land abandonment has resulted in a
lack of maintenance of the terrace walls and the onset of a general process of land
degradation. The objective of this study is the quantification of soil erosion in a small
terraced catchment (10,000 m2), located on the north-eastern slope of the Troodos
Mountains (Cyprus), at an elevation of 1,300 m a.s.l. The catchment is cultivated with
vineyards and it is representative of the main agricultural land use in the Troodos
region. Soil erosion is measured by sediment traps and laser scans are made to
assess changes in terrace geometry. In addition, a weather station measuring rainfall,
temperature and relative humidity has been installed in the catchment, along with 18 soil
moisture sensors, to relate soil erosion processes with climate and (sub)surface
hydrology. A total of 10 sediment traps, five pairs, have been installed in the study
site, catching five well-maintained sections of a dry-stone wall and five degraded
(collapsed) sections. Each trap is 1 m wide. In detail, two terraces, 11 and 14 m long,
located at the same elevation and separated by a strip of natural vegetation, are
monitored with four and six traps, respectively. To get a complete picture of the erosion
processes occurring on the selected area, the trap pairs collect sediment from both the
collapsed and the well maintained wall sections of the two terraces. In addition,
terrace area of two traps is delineated by metal borders (1x4 m2) to relate erosion
rates to a known drainage area. The sediment traps are emptied after all rainfall
events. At the beginning and end of the rainy season, a laser scanning survey of a
terrace located uphill of the ones monitored by sediment traps is performed. The
scan produces a point cloud with a resolution close to 2 mm. The comparison of
the 3D models derived in different times allows detecting changes in the terrain
topography, which can be transformed in to erosion rates knowing the soil bulk
density. The preliminary results of the monitoring experiment, which started at the
beginning of November 2015, show erosion rates an order of magnitude higher
in the collapsed sections of the terrace wall in comparison to the preserved ones.
A more comprehensive analysis relating erosion rates to precipitation intensity,
assessing yearly erosion rates in degraded terraced environments and comparing
different monitoring techniques are expected at the end of the rainy season (April). |
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