『Abstract
Erosion and sediment redistribution are important processes in
landscape changes in the short and long term. In this study, the
RMMF model of soil erosion and the SEDD model of sediment delivery
were used to estimate annual soil loss and sediment yield in an
ungauged catchment of the Spanish Pre-Pyrenees and results were
interpreted in the context of the geomorphic features. The Estana（nの頭に〜） Catchment is divided into 15 endorheic
sub-catchments and there are 17 dolines. Gullies and slopes were
the main erosive geomorphic elements, whereas the colluvial, alluvial,
valley floor, and doline deposits were depositional elements.
Spatially distributed maps of gross soil erosion, sediment delivery
ratio (SDR), and sediment yield (SY) were generated in a GIS.
Severe erosion rates (＞100 Mg ha-1 year-1)
were found in gullies, whereas mean and maximum erosion rates
were very high on slopes developed on Keuper（uの頭に¨）
Facies and high in soils on Muschelkalk Facies. Where crops are
grown, the depositional-type geoforms were predicted by the models
to have an erosive dynamic. Those results were consistent with
the rates of erosion quantified by 137Cs which reflects
the significant role of human activities in triggering soil erosion.
Catchment area was positively correlated with erosion rate, but
negatively correlated with SDR and SY. The latter were negatively
correlated with the proportion of the surface catchment covered
with forests and scrublands. The topography of the area influenced
the high SDR and SY in the dolines and valley floors near the
sinks. Intra-basin stored sediment was 59.2％ of the total annual
eroded soil in the catchment. The combination of the RMMF and
SEDD models was an appropriate means of assessing the effects
of land uses on soil erosion and obtaining a better understanding
of the processes that underlie the geomorphic changes occurring
in mountainous environments of the Mediterranean region.
Keywords: RMMF model; SEDD model; Soil erosion; Sediment delivery
and yield; Geomorphology』
Introduction
Materials and methods
Study area
The RMMF model of soil erosion applied in a GIS
Soil detachment by splash
Soil detachment by runoff
Runoff transport capacity
The SEDD model of sediment delivery and yield
Data collection
Results
Runoff and soil erosion
Sediment delivery ratio and sediment yield
Discussion
Conclusion
Acknowledgments
References