Multi-temporal soil erosion risk assessment in N. Chalkidiki using a modified USLE raster model
Ioannis Z. Gitas, Kostas Douros, Chara Minakou, George N. Silleos and Christos G. Karydas
Abstract
The aim of this work was to test a modified
version of the Universal Soil Loss Equation (USLE) for assessing the risks of
erosion in N. Chalkidiki, Greece. USLE
estimates the severity of erosion, thus assisting the decision process in
selecting erosion control measures. Although USLE has several limitations, it
was selected because it is the simplest approach while remaining robust, and it
partially solves the problem of data availability. Modifications referred to here
concerned the estimation of factors C and k (representing land management and soil vulnerability,
respectively). More specifically, the C-factor
was estimated using multi-temporal NDVI
layers derived from LANDSAT images, while the k-factor was estimated based on the geological map. All USLE
factors were calculated as grid layers after processing the original data, then
they were multiplied together (according to the USLE) in order to derive the final risk map
for three different seasons. A scale of 1:100 000
was selected and the mapping unit was set at 1 ha. The results, assessed for their accuracy by experts, showed that the
use of multi-temporal NDVI gave a
better insight than a single date approach in understanding the erosion
procedures in the study area and facilitated the comparison between seasons and
areas.
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History
Submitted: 29 Aug 2008
Revised: 06 Mar 2009
Accepted: 13 Mar 2009
Published: 04 Apr 2009
Responsible editor: Bogdan Zagajewski
Citation
Gitas I Z, K Douros, C Minakou, G N Silleos & C G Karydas, 2009.
Multi-temporal soil erosion risk assessment in N. Chalkidiki using a modified USLE raster model.
EARSeL eProceedings, 8(1): 40-52
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