The EUROSEM model was applied to three drainage basins in Valencia, Spain to study erosion problems and evaluate soil losses under current and changed conditions. Topography was represented using GIS and a digital elevation model. The basins were divided into homogeneous elements based on slope, geology, soils, and vegetation. Model results showed infiltration, runoff, and erosion/sedimentation values. Applying the model with heavy rain scenarios showed increased erosion risk and soil loss tripling, demonstrating how weather changes can worsen erosion in drainage basins.

1. Application of the EUROSEM model in drainage
basins in areas of the Valencian Community
Soriano MD1, García-España L2, Montoya, J.M1
1 Universitat Politècnica de València, Cami de Vera s/n Valencia, Spain, asoriano@prv.upv.es
2 Universitat de València, Andres Estelles s/n Burjassot Valencia, Spain, laugarcia@uv.es
RESULTS
The topographical representation of the terrain
carried out through the Geographic
Information System (GIS) for the three zones
has allowed the digital quantitative
representation of the topographical surface of
the terrain shown in Figure 1 to be obtained.
The altitudes of the watersheds range from 150
m. to 525 m in the Murta and 630 m in La
Casella, and between 300 and 750 m in the
Vall d´Ebo. The Lithologic map differentiates
areas of limestone and loam lithology in both
zones located on the slopes and fillings of the
valley.
Element
Contribution
Area (m2)
Total Runoff (m3)
Stage 1
Total Runoff (m3)
Scenario 3
32 225.991 62.003 151.523
45 45.493 6.340 12.611
94 146.901 12.001 23.198
136 126.327 9.300 11.432
152 62.873 2.215 3.456
32 225.991 62.003 151.523
45 45.493 6.340 12.611
Table 1. Values of total runoff results in scenarios 1 and
3 in some basin units.
The identification of areas where soil loss
predominates, transport areas and areas
where sedimentation occurs, makes it
possible to highlight the points where erosive
phenomena are critical. This information is
of great relevance when it comes to
individualizing practices of prevention,
correction or mitigation in the plans that
require intervention. In the area of the Murta
soil erosion losses are represented in ranges
ranging from light erosion with values lower
than < 1 t/ha, low and moderate erosion with
ranges up to-8 t/ha, high of 8-12 t/ha and
very-high higher than 12 t/ha. 65% of the
zone corresponds to low erosion ranges
favored in most cases by high plant cover
values and located on the northern slopes
and in low sediment deposition areas (basin
center) 26% of the area corresponds to areas
of moderate and high erosion and the rest to
areas of very high erosion.
a b c
a b c
Fig. 3. Model EuroSEM according to DTM version field a)
infiltration (mm), b) runoff (m3), c) erosion-deposition
(t/ha)
Fig. 4. Units Map of the Vall of Murta
ABSTRACT
The results of the application of the EUROSEM
model are compared in different drainage basins
in the Spanish provinces of Valencia and
Alicante (Vall d'Ebo, Sierra de la Murta and La
Casella). The goal is to study erosion problems
by evaluating soil losses -due to erosion in the
current situation- and study the effect of the
change of conditions and its repercussions in
order to apply palliative techniques.
The aim of this study is to evaluate the erosive
phenomena using the EUROSEM model GIS. In
addition, the tool, MDT, is used to represent the
topography of the area. A generalized drainage
model is constructed by calculating the flow
direction, and identifying homogeneous units
depending on various parameters evaluated
(slope, geology, soils, and vegetative coverage),
thus obtaining a schematic representation of the
basin with different units / EUROSEM elements.
For this purpose, soil samples were analyzed
with a detailed study of vegetation, mulch,
stoniness, grooves, roughness, and so forth. As
well as considering the precipitation data
obtained from an automated weather station in
the basin.
In the application of the model and making
modifications of the parameters, important
differences are obtained in values such as
infiltration, run-off, and erosion/sedimentation.
These sites are located in zones with major risk
of erosion and in zones of major concentration
of superficial flow which are a consequence of
the hydrological connectivity and the effect of
heavy rain. The results show the effects of rain
on the loss of soil by erosion in the zones
studied, showing that the tons of eroded soil
would triple. These results indicate how a
change in weather conditions can increase the
values of soil loss by erosion in drainage basins.
CONCLUSION
Hydrological in the form of homogeneous
planes interconnected by flow channels, where
water and sediments experience a downward
movement without lateral movements.
The simulation with heavy rainfall results in
an increase in the risk of erosion.
a b
Fig. 1. a) Conectivity units b)Raster of the Digital Elevation
Model (DEM) of the Vall of Murta (Valencia). Units Map.
Fig. 2: Model EuroSEM
according to DTM version a)
infiltration (mm), b) runoff (m3),
c) erosion-deposition (t/ha)