PDF Archive

Easily share your PDF documents with your contacts, on the Web and Social Networks.

Share a file Manage my documents Convert Recover PDF Search Help Contact



Agrienvironmental indicator soil erosion .pdf



Original filename: Agrienvironmental_indicator_soil_erosion.pdf
Title: Agri-environmental indicator - soil erosion
Author: Eurostat

This PDF 1.4 document has been generated by PDFCreator Version 1.7.1 / GPL Ghostscript 9.07, and has been sent on pdf-archive.com on 18/10/2013 at 00:02, from IP address 87.5.x.x. The current document download page has been viewed 739 times.
File size: 250 KB (10 pages).
Privacy: public file




Download original PDF file









Document preview


Agri-environmental indicator - soil erosion
Eurostat 1
1

Statistical office of the European Union
From Statistics Explained

This article provides a fact sheet of the European Union (EU) agri-environmental indicator soil erosion. It consists of an
overview of recent data, complemented by all information on definitions, measurement methods and context needed to interpret
them correctly. The soil erosion article is part of a set of similar fact sheets providing a complete picture of the state of the
agri-environmental indicators in the EU.
The indicator soil erosion estimates the areas affected by a certain
rate of soil erosion by water.
Main indicator:
Areas with a certain level of erosion (aggregated to NUTS 3
regions).
Supporting indicator:
Estimated soil loss by water erosion (tonnes per ha per year).

Contents
1 Main statistical findings
1.1 Key messages
2 Assessment
3 Data sources and availability
3.1 Indicator definition
3.2 Measurements
3.3 Links with other indicators
3.4 Data used and methodology
4 Context
4.1 Policy relevance and context
4.2 Agri-environmental context
5 Further Eurostat information
5.1 Publications
5.2 Dedicated section
5.3 Source data for tables, figures and maps (MS
Excel)
5.4 Other information
6 External links
7 See also
8 Notes

Example of soil water erosion on arable land
© Joint Research Centre, European Commission

Main statistical findings
Key messages
According to recent studies, approximately 15 % of
the European Union (EU) territory (data not available
for Cyprus, Greece and Malta) is estimated to be affected by a
significant soil erosion rate (moderate to high level). Mean
rates of soil erosion by water in EU-27 amounted to 2.76
tonnes per hectare per year and was higher in the EU-15 (3.1

Map 1: Soil erosion by water (tonnes per ha per year),

tonnes per hectare per year) (data not available for
Greece) than in the 12 Member States which joined the EU in
2004 and 2007 (1.7 tonnes per hectare per year) (data not
available for Cyprus and Malta).
Just over 7 % of cultivated land (arable and permanent
cropland) in EU (excluding Cyprus, Greece and Malta) is
estimated to suffer from moderately-high to high erosion. This
equates to 115 410 km2 or approximately the entire surface
area of Bulgaria. 1 % of the EU land surface suffers from
extreme erosion (over 50 tonnes per hectare per year).
Only 2 % of permanent grasslands and pasture in EU
(excluding Cyprus, Greece and Malta) is estimated to suffer
from moderate to severe erosion. This equates to around 9 000
km2. This demonstrates the importance of maintaining
permanent vegetation cover as a mechanism to combat soil
erosion.

2006, EU-27, NUTS 3
Source: Joint Research Centre, European Commission

Assessment
This fact sheet describes the susceptibility of soil to erosion by water
across Europe, including current estimated levels and historical
trends. The trend information identifies those countries or areas for
which an improvement and/or deterioration in soil erosion rate can be
observed. It is important to note that both indicators are outputs of a
modelling exercise and are estimates rather than measured values.
Erosion can be defined as the wearing away of the land surface by
physical forces such as rainfall, flowing water, wind, ice, temperature
change, gravity or other natural or anthropogenic agents that abrade,
detach and remove soil or geological material from one point on the
earth's surface to be deposited elsewhere. When used in the context
of pressures on soil, erosion refers to accelerated loss of soil as a
result of anthropogenic activity, in excess of accepted rates of natural
soil formation[1]. The loss of soil leads to a decline in organic matter
and nutrient content, the breakdown of soil structure, a reduction of
the available soil water stored, which can lead to an enhanced risk of
flooding and landslides in adjacent areas. Nutrient and carbon cycling
can be significantly altered by mobilization and deposition of soil[2],
as eroded soil may lose 75 - 80 % of its carbon content, with
consequent release of carbon to the atmosphere[3]. Soil erosion
impacts strongly on the environment and has high economic costs; to
mitigate these effects, soil and water conservation strategies are
required.

Map 2: Soil erosion by water (tonnes per ha per year),
2006, EU-27, 1km cell size
Source: Joint Research Centre, European Commission

Soil erosion by water is one of the most widespread forms of soil
degradation in the European Union. Map 1 shows the soil water
erosion across all land surfaces in EU. No results are reported for
Cyprus, Greece and Malta due to a lack of harmonised landcover
data. This map presents the mean level of soil water erosion in
administrative areas by NUTS 3 level with a range starting from a
Figure 1: Percentage of the EU territory affected by soil
very low level (less than 0.5 tonnes per hectare per year) to a level
water erosion (%) according to soil erosion rate
which is considered as high (more than 20 tonnes per hectare per
(tonnes per ha per year), 2006, EU-27
Source: Joint Research Centre, European Commission
year). Map 2 represents the water erosion in tonnes per hectare per
year (cell size: 1 km) across all land surfaces in EU. No results are
reported for Cyprus, Greece and Malta due to a lack of harmonised
landcover data. Note that patterns and maximum values may differ slightly from Map 1 due to the smoothing effect that results in
the calculation of mean values for administrative regions (i.e. in Map 1 low and high values are not visible in individual NUTS 3
polygons).
According to recent studies, approximately 15 % of the EU territory is estimated to be affected by a significant soil erosion rate
(moderate – high level or more than 5 tonnes per ha per year) (Figure 1). This is in line with previous estimations that 16 % of
European Union's land area is affected by soil erosion[4]. Mean rates of soil erosion by water in the EU amounted to 2.76 tonnes
per hectare per year and was higher in the EU-15 (3.1 tonnes per hectare per year) than in the 12 Member States which joined
the EU in 2004 and 2007 (1.7 tonnes per hectare per year) (Figure 2).
Just over 7 % of cultivated land (arable and permanent cropland) in EU is estimated to suffer from moderate to high erosion

(more than 5 tonnes per hectare per year). This equates to an area of
115 410 km2 (close to the entire surface area of Bulgaria). Using
conservative estimates of wheat yields of 1 tonne per hectare and a
market price of EUR 300 per tonne of wheat, in an area of cultivated
land affected by moderate to severe soil erosion, agricultural
production in the region of EUR 3.5 billion could be under threat. If
the economic value is placed on the loss of soil carbon (currently
CO2 credits are around EUR 20 per tonne), the figure would be even
higher.
Several countries in the southern part of Europe show mean erosion
rates that are significantly higher than the mean value for EU (Figure
3). However, countries with low mean erosion rates may contain
areas where erosion rates are significantly higher (and of course, vice
versa). No harmonized measure of soil erosion rates exists for the
European continent. To date, the only harmonized pan-European
estimates of soil erosion by water have been provided by the
PESERA project (http://eusoils.jrc.ec.europa.eu/esdb_archive/pesera
/pesera_download.html) [5]. This fact sheet is based on a
methodology to improve on the limitations of the PESERA model.
Increasing awareness amongst scientists and policy-makers about the
problem of soil degradation through erosion in Europe has made the
quantification of its extent and impact an urgent requirement. The
identification of areas that are vulnerable to soil erosion can be
helpful for improving our knowledge about the extent of the areas
affected and, ultimately, for developing measures to keep the problem
under control.
Considering the average of soil water erosion rate by country (Figure
3), several European countries appear not to be significantly affected
by notable soil erosion susceptibility when compared to a ‘continental
mean’ of around 2 tonnes per hectare per year. However, such values
can be misleading as they mask the fact that erosion rates in many
areas can be much higher, even for those countries that have a low
mean rate of erosion. The converse is also true for countries with high
values. On the other hand, some countries, mainly in the southern
part of Europe, are clearly characterised as being particularly
susceptible to erosion.
There are some exceptions (e.g. northern Scotland). There is a high
probability that the erosion rate is over-estimated in some areas due
to the low value of explained variance for the calculation of the
rainfall erosivity factor and the presence of many areas having an
actual stoniness value that is much higher than the value indicated by
the underlying soil database.
Soil stoniness is known to have a strong influence on erosion rates[6].
Rock fragments in the soil top layers affect soil water erosion
processes in various ways, both direct and indirect. Direct effects on
soil erosion comprise the shielding of the soil surface from
detachment by raindrop splash and runoff or the interception of
splashed sediment. Indirect effects are numerous but the most
important ones are the effects of rock fragments on physical
properties of the fine earth (e.g. porosity, organic matter content)
affecting soil erosion sub-processes, physical degradation (i.e. surface
sealing, compaction) of the soil top layer, hydrological processes
affecting runoff generation and discharge (e.g. infiltration,
percolation) and hydraulics of runoff.
There has been much discussion in the literature about thresholds
above which soil erosion should be regarded as a serious problem.
This has given rise to the concept of ‘tolerable’ rates of soil erosion
that should be based on reliable estimates of natural rates of soil
formation. However, soil formation processes and rates differ
substantially throughout Europe. In some cases, rates of soil erosion
larger than 1 tonne per hectare per year are regarded as tolerable
from the wider perspective of society as a whole, for example for
economic considerations or the preservation of soil functions. In

Figure 2: Mean rates of soil erosion by water (tonnes
per ha per year), 2006, EU-27
Source: Joint Research Centre, European Commission

Figure 3: Soil water erosion rate by country (tonnes per
ha per year), 2006, EU-27, EFTA, Candidate and
Potential Candidate Countries
Source: Joint Research Centre, European Commission

Map 3: Soil water erosion trends, 2000-2006, EU-27,
NUTS 3
Source: Joint Research Centre, European Commission

Switzerland, the threshold tolerated for soil erosion is generally 1
tonne per hectare per year, though this rate can be increased to 2
tonnes per hectare per year for some soil types[7]. In Norway, 2
tonnes per hectare per year is adopted as the threshold for tolerable
soil loss. In general, losses above 1 tonne per hectare per year are
generally considered as irreversible. Nevertheless, there may be a
need to propose different thresholds of rates of soil erosion that are
tolerable in different parts of Europe. However, this aspect needs
further elaboration.
Soil erosion trends resulting from changes in land cover and rainfall
erosivity have also been analyzed. A time interval of six years was
evaluated (2000 - 2006) (Map 3). The results do not show any
particular trend in the erosion of soil by water. This finding is
contrary to the results of some simulations using Intergovernmental
Panel on Climate Change (IPCC) (http://www.ipcc.ch/) scenarios
(2070 - 2100)[8] but due to the time interval analysed, any
conclusions must be made with caution. To understand better the real
trend, an analysis over a time period of at least 15 - 20 years would
be necessary (e.g. comparing the current situation to the 1990s).

Map 4: Soil erodibility factor (K) in Europe
Source: Joint Research Centre, European Commission

Data sources and availability
Indicator definition
The indicator soil erosion estimates the areas affected by a certain
rate of soil erosion by water.
Measurements
Main indicator:
Areas with a certain level of erosion (aggregated to NUTS 3)

Map 5: Cover management factor (C) in Europe
Source: Joint Research Centre, European Commission

Supporting indicator:
Estimated soil loss by water erosion (tonnes per hectare per year)
Links with other indicators
Soil erosion does not serve as an input to other AEI, but has indirect links to the following indicators:
AEI 09 - Land use change
AEI 10.1 - Cropping patterns
AEI 11.1 - Soil cover

AEI 11.2 - Tillage practices
AEI 12 - Intensification/Extensification
AEI 14 - Risk of land abandonment

Data used and methodology
Two soil erosion indicators have been produced on the basis of empirical computer model.
The main indicator represents estimated soil erosion levels for NUTS Level 3 administrative areas that range from very low
values (less than 0.5 tonnes per hectare per year) to high values (more than 20 tonnes per hectare per year) for the EU.
The second indicator is a cell-based map that estimates the rate of soil erosion by water in Europe in tonnes per hectare per
year for cells of 1 km x 1 km for the EU.
The indicators are predicted estimates and not actual values. They are derived from an enhanced version of the Revised
Universal Soil Loss Equation (RUSLE) (http://www.ars.usda.gov/Research/docs.htm?docid=5971) model [9] which was
developed to evaluate soil erosion by water at a regional scale. The model was developed primarily to guide conservation
planning, inventory erosion rates and estimate sediment delivery on the basis of accepted scientific knowledge and technical
judgment. In this assessment, the basic RUSLE model has been adapted through the addition of a new factor that improves the
estimation of the effect of stoniness on soil erosion. The RUSLE model has been used due to its flexibility in relation to input data
requirements. In addition, a novel approach was used to develop input data on the erosivity of precipitation.
Only soil erosion resulting from rainsplash, overland flow (also known as sheetwash) and rill formation are considered. These are
some of the most effective processes to detach and remove soil by water. In most situations, erosion by concentrated flow (rills
and gullies) is the main agent of erosion by water. Readers should be aware that due to the scale of the input data, the results
provide an overview of the soil erosion susceptibility in the landscape rather than a real estimation for a specific location.

A major consideration in any modelling exercise is the quality of the input datasets. Many pan-European datasets are small-scale
(e.g. 1:1 000 000) or coarse in their resolution (e.g. 1 - 10 km cells). Data limitations stimulated an innovative approach to
estimate the erosivity of rainfall through the development of a climatic-based ensemble model which merged multiple empirical
equations of rainfall erosivity. These equations were collected from specific case studies published in the literature covering a
range of climatic areas throughout Europe. The merging was done by extending the original geographical domain of validity of
each equation to similar climatic areas.
Due to limited measurement data across Europe, the validation of modelled data is problematic.
The RUSLE model benefits from an array programming paradigm[10][11] which allows the final assessment to be calculated on
the basis of a series of scale-independent modules. This allows users to process large volumes of data. The revised version of the
RUSLE is an empirical model that calculates soil loss due to sheet and rill erosion. The model considers seven main factors
controlling soil erosion: the erosivity of the eroding agents (water), the erodibility of the soil, the slope steepness and the slope
length of the land, the land cover, the stoniness and the human practices designed to control erosion.
The model estimates erosion by means of an empirical equation: Er = R K L S C St P
Where:
Er = (annual) soil loss (tonnes per hectare per year).
R = rainfall erosivity factor
K = soil erodibility factor
L = slope length factor (dimensionless).
S = slope steepness factor (dimensionless).
C = cover management factor (dimensionless).
St = stoniness correction factor (dimensionless)
P = human practices aimed at erosion control (dimensionless).
Rainfall erosivity factor (R). The intensity of precipitations is one of the main factors affecting soil water erosion
processes. R is a measure of the precipitation’s erosivity and indicates the climatic influence on the erosion phenomenon
through the mixed effect of rainfall action and superficial runoff, both laminar and rill. Wischmeier[12] identified a
composite parameter EI, as the best indicator of rain erosivity. It is determined, for the ki-th rain event of the i-th year, by
multiplying the kinetic energy of rain by the maximum rainfall intensity occurred within a temporal interval of 30 minutes.
Due to the difficulty in obtaining precipitation data with adequate temporal resolution over large areas, the R factor has
been calculated using a series of simplified equations available in scientific literature. In the present application, an
innovative climatic-based ensemble model to estimate erosivity from multiple available empirical equations has been
created for the pan-European maps[13]. The R factor has been computed using the E-OBS database (http://eca.knmi.nl
/download/ensembles/download.php) as data source[14]. E-OBS is based on the largest available pan-European
precipitation data set, and its interpolation methods were chosen after careful evaluation of a number of alternatives.
Soil erodibility factor (K) (Map 4). The soil erodibility factor represents the effects of soil properties and soil profile
characteristics on soil loss[15]. The K factor is affected by many different soil properties and therefore quantifying the
natural susceptibility of soils is difficult. For this reason, K is usually estimated using the soil-erodibility nomograph[16].
The European Soil Database (SGDBE) (http://eusoils.jrc.ec.europa.eu/esdb_archive/esdbv2/fr_intro.htm) at 1:1.000.000
scale has been used for the calculation (see also[17]).
Topographic factors - slope length (L) and slope steepness (S). The effect of topography within the RUSLE model is
accounted for by the slope length factor and the slope steepness factor. For the calculation of the L and S factors, the
Shuttle Radar Topography Mission (SRTM) (http://www2.jpl.nasa.gov/srtm/) [18] digital terrain model was used as it is one
of the most complete high-resolution digital topographic databases of the Earth.
Cover-Management factor (C) (Map 5). The cover-management factor represents the influence of land cover, cropping
and management practices on erosion rate. The calculation of the C factor is very difficult due to the lack of detailed
information in Europe. In this study, the C-factor has been calculated using average values from literature[19][20][21] and
the Corine Land Cover (http://www.eea.europa.eu/publications/COR0-landcover) database for 2006 and [22] The impact
of natural vegetation suggests further analysis with detailed forest types and tree species distribution maps[23][24][25] to
increase the corresponding C factors accuracy.
Stoniness Correction factor (St). The stoniness correction factor has been introduced to correct the negative relation
between rock fragment cover and relative inter-rill sediment yield. The RUSLE model considers stoniness indirectly within
the K and the C factor. Regarding the K factor, as already mentioned, only the effects of rock fragment within the soil
profile are considered. For the C factor stoniness is taken into account in calculating the Surface Cover subfactor. For the
calculation of the St factor, the equations of Poesen and Lavee[26] have been applied to the European Soil Database
(SGDBE) where IR = e -b(Rc) with IR being the inter-rill sediment yield, b being a coefficient indicating the effectiveness
of the rock cover (Rc,%) in reducing inter-rill soil loss. Poesen and Ingelmo-Sanchez[27] found a b-value of 0.02 for partly
embedded rock fragments and a b-value of 0.04 for fragments placed on the soil surface. Unfortunately detailed
information on soil stoniness does not exist for Europe. However, the ESGDB database contains information about the
stoniness volume of soils with an important rock fragment content. Stony soils cover about 30 % of the surface soils of
Western Europe, and 60 % in Mediterranean areas. They consist of rock fragments whose diameters are larger than 2 mm
(the rock fragment). These fragments may alter the physical, chemical and agricultural properties of soils[28]. Various

studies indicate that these stony soils are at least partly a result of their often long and intense history of deforestation and
cultivation, during which erosion rates were larger than the long-term soil formation rate[29][30][31][32][33]. Although stony
soils do not necessarily generate less runoff, they are considerably less susceptible to water erosion[34].
Human Practices factor (P). This factor includes land management practices (such as terracing, strip cropping or
ploughing direction) that affect erosion phenomena. For areas where there are no support practices or without any data, the
P factor is set to 1.0.
A number of issues should be noted:
The model estimates soil loss caused by raindrop impact, overland flow (or sheetwash) and rill erosion. It does not estimate
gully or stream-channel erosion. As a consequence, the risk of soil degradation in areas affected by different erosion
phenomena (gully erosion, wind erosion, etc.) are probably underestimated.
As mentioned previously, the lack of high-resolution pan-Europe environmental datasets, the non linearity present within
the climatic-based ensemble model and the underlying principles of the RUSLE model that considers only some categories
of soil erosion lead to a level of uncertainty in the output predictions. As a consequence, quantitative assessments using the
model should not be undertaken without the right awareness.
There are also great difficulties in gathering enough information to drive an adequate validation of the model results, but
this aspect applies to the output from any large area erosion-prediction model. The validation of erosion estimates at
continental scale is not technically and financially feasible. One validation option is through the upscaling of local
monitoring studies of large-scale modelling assessments.
The selection of input datasets in the development of this indicator is a crucial process as they have to offer the most
homogeneous and complete spatial coverage of the target area.
The model must also allow the produced information to be harmonized and easily validated.
In the case of this indicator, an alternative qualitative validation method, based on expert judgement was applied. Modelled
results were compared with the soil erosion maps provided by different countries through the European Environment
Information and Observation Network (EIONET) (http://www.eionet.europa.eu/) (EIONETSOIL). Most of the maps in
this exercise were also calculated using the RUSLE model, using higher resolution datasets or containing less uncertainty.
Overall, the results show a high correlation in the pattern of the erosion. Furthermore, a qualitative evaluation is being
carried out based on the analysis of soil erosion evidence on satellite images and pictures published in Google Earth.

Context
Soil is a valuable, non-renewable resource that offers a multitude of ecosystems goods and services. Soil erosion is the wearing
away of the land surface through the action of water and wind, and is exacerbated by tillage and other disturbances (e.g. removal
by crop harvesting, dissolution and river bank erosion). At geological time-scales there is a balance between erosion and soil
formation[35]. However, in many areas of the world there is an imbalance with respect to soil loss and its subsequent creation,
caused principally by anthropogenic activities (mainly as a result of land use change) and climate change.
The Thematic Strategy for Soil Protection (http://ec.europa.eu/environment/soil/three_en.htm) and the proposed Soil Framework
Directive (http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:52006PC0232:EN:NOT) recognise soil erosion as a
major threat to the soil resources of Europe and is one of three priority areas for policy recommendations. Soil erosion requires
immediate attention and irreversible degradation is to be avoided in certain landscapes of Europe. Climate, vegetation cover, land
use, topography and soil characteristics as well as conservation practice have a strong impact on soil erosion rates. Soil erosion
reduces the ecological functions of soil over time. The main on-site consequences regard biomass production and crop yields (due
to removal of nutrients and reduction in soil filtering capacity).
The Mediterranean area is particularly prone to soil water erosion because of long dry periods followed by heavy bursts of
intense precipitations on steep slopes with fragile soils. In some areas, erosion has reached a state of irreversibility with the
complete removal of all soil material.
Soil erosion in northern Europe is generally less pronounced because of the lower erosivity of the rain and the higher vegetation
cover. However, arable lands in this part of Europe are also susceptible to erosion, especially loamy soils after ploughing[36], as
are some areas under natural vegetation.
Given the increasing threat of erosion by the detachment of soil particles by water in Europe, and the implications this has on
future food security and water quality, it is important that land managers are provided with accurate and appropriate information
on the amount of soil that is actually being lost. It is impractical and technically difficult to measure soil loss across whole
landscapes and thus research is urgently needed to improve methods of estimating soil erosion using modelling, upon which
mitigation can be implemented.
A wide variety of models are available for soil water erosion estimation. The selection of a model depends mainly on the purpose
for which it is intended and the available dataset. Some models are designed to predict soil erosion from single storms while
others predict long-term effects. Models such as the Universal Soil Loss Equation and derived versions[37] are developed to
predict only sheet and rill soil erosion and do not take into account other processes like gully erosion. Most models have been
designed for local scale applications. Therefore, several problematic issues occur when applying quantitative soil erosion models
at regional-level or for smaller scale mapping. At these levels, the spatial resolution of the dataset is too coarse to ascertain
accurately a single specific erosion process (i.e. it is impossible to differentiate between rill erosion and gully development). In
addition, the poor resolution of the spatial data used as model inputs can limit their use in some applications. Uncertainties in the
model inputs propagate throughout the model so that the quality of the model input is strictly linked with the quality of model
results. Consequently, care should be taken not to use an ‘over-parameterised’ model when the quality of the input data is poor.
At the regional scales, outputs need to be interpreted carefully and a reliable estimation of absolute soil erosion rates is almost

impossible to obtain. Because of all these issues the relative values obtained when applying soil erosion models at regional levels
are generally more reliable than the absolute values. Readers should be aware that the model gives a broad overview of the soil
water erosion phenomena in the landscape rather than providing an accurate value for a specific point.
The soil erosion indicators presented here have been obtained by applying a soil water erosion model. Two indicators are
proposed to locate the areas with an estimated level of erosion.
Only soil erosion resulting from rainsplash, overland flow (also known as sheetwash) and rill formation are considered. In most
situations, erosion by concentrated flow (rills and gullies) is the main agent of erosion by water. These are some of the most
effective processes to detach and remove soil by water:
Rainfall has the ability to move soil particles directly. This is known as rainsplash erosion. This action is only effective if
the rain falls with sufficient intensity. When raindrops hit bare soil, their kinetic energy is able to detach and move soil
particles a short distance. Because soil particles can only be moved short distances (few millimetres at the most), its effects
are solely on-site. Although considerable quantities of soil may be moved by rainsplash, it is generally all redistributed back
over the surface of the soil. On steep slopes, there can be a modest net downslope movement of splashed soil due to the
effect of gravity and the gradient of the land. Rainsplash erosion requires high rainfall intensities such as those that
accompany convective rainstorms. Rainsplash erosion also weakens the soil surface structure, making it more vulnerable
for transport by overland flow.
Overland flow occurs either when the soil is infiltrated to full capacity and excess water from rain, meltwater or other
sources, flows over the land as a sheet. Alternatively, the rainfall rate may be higher than the infiltration rate of the soil.
Sheetwash erosion occurs without any well defined channel and can manifest itself across entire slopes. As a consequence,
the erosion can affect large areas and move significant amounts of soil.
Rills occur when overland flow begins to develop preferential flow paths. In turn, these flow paths are eroded further
which results in small, well-defined linear concentrations of overland water. In many cases, small rills may disappear over
time due to sedimentation. However, persistent micro-rills can develop further to become rills, with a subset eventually
becoming gullies.
Gullies are deeper channels, often resulting from unchecked rill erosion. Due to their size, gullies are capable of moving
large amounts of soil, into larger channels such as streams and rivers and thus out of the original site. Gully erosion is not
considered in the RUSLE model.
Other forms of erosion (for example, gully erosion and wind erosion) are important and should be considered in the future.
Policy relevance and context
The European Union’s Sixth Environment Action Programme (http://europa.eu/legislation_summaries/agriculture/environment
/l28027_en.htm) (Environment 2000-2010: our future, our choice. Decision 1600/2002 (http://eur-lex.europa.eu/LexUriServ
/LexUriServ.do?uri=CELEX:32002D1600:EN:NOT) of the European Council and Parliament) declared a necessity to protect
soil against degradation, due to the influence of human actions. This resulted in the publication of a Thematic strategy for soil
protection (http://ec.europa.eu/environment/soil/three_en.htm) (Communication from the Commission to the Council, the
European Parliament, the European Economic and Social Committee and the Committee of the Regions - Thematic Strategy for
Soil Protection COM final 0231/2006 (http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:52006DC0231:EN:NOT)
). Through this Strategy, the European Union has defined an action plan for soil conservation in Europe. With the EU Soil
Thematic Strategy, the objective to define a common and comprehensive approach to soil protection, focusing on the
preservation of soil functions, has been introduced. It is based on the principles of:
preventing further soil degradation and preserving its functions, and
restoring degraded soils to a level of functionality consistent at least with current and intended use.
The Soil Thematic Strategy considers a number of soil degradation processes, including erosion, that should be identified and for
which appropriate measures should be put in place to preserve soil functions.
Soil has not been subject to a dedicated protection policy at EU level. Provisions for soil protection are spread across many
different areas, either under environmental protection or other policy areas such as agriculture and rural development. These
provisions are considered to not offer a sufficient level of soil protection. A coordinated action at European level would therefore
appear necessary, hence the adoption of the Soil Thematic Strategy and of the proposed Soil Framework Directive. The state of
soil influences other environmental and food safety aspects governed at EU level giving an international dimension of the
problem. The common agricultural policy (CAP) contributes to preventing and mitigating soil degradation processes. In
particular, agri-environment measures (http://ec.europa.eu/agriculture/envir/measures/index_en.htm) (which offer opportunities
for favouring the build-up of soil organic matter, the enhancement of soil biodiversity, the reduction of soil erosion,
contamination and compaction) and cross-compliance (http://ec.europa.eu/agriculture/envir/cross-compliance/index_en.htm)
(which can play an important role for soil protection).
Agri-environmental context
Soil erosion costs the economy a large amount of money. Research on the quantification of external effects of soil erosion is more
advanced in the United States of America and Australia than in Europe. Only a few examples can be shown for Europe but
sufficient cases exist to establish a reliable impression of the real situation. J.N.Pretty calculated that the annual external costs for
agricultural production in the UK from soil erosion were almost EUR 3.5 billion and at least EUR 1.8 billion in Germany[38].
On-site effects of water soil erosion (loss of organic matter and nutrients, soil structure degradation, plant uprooting, reduction of

available soil moisture, etc.) are particularly important on agricultural areas resulting in a reduction of cultivable soil depth and a
decline in soil fertility. The loss of soil productivity following erosion may be significant. Topsoil, which is the most fertile layer of
the soil, is the most exposed to erosion; also the mechanisms of soil erosion preferentially remove soil organic matter, clay, and
fine silt material. Soil erosion also reduces the volume of soil available for plants roots and degrades soil physical properties (such
as water holding capacity). In most cases extra fertilizer can compensate the impacts of soil erosion on soil fertility, but it
represents an extra cost for farmers, and does little to offset the physical impacts of erosion on soil productivity.
Off-site effects of soil water erosion arise from sedimentation, which causes infrastructure burial, changes in watercourses shape
and obstruction of drainage networks enhancing the risk of flooding and shortening the life of reservoirs. Many irrigation or
hydroelectricity projects have been damaged by soil water erosion.
Generally, high intensity agricultural land use leads to higher soil loss by water and wind erosion, especially in potentially high
erosion risk areas. However, the reverse could equally be true. For example, an intensive farming system employing soil
conservation measures such as terracing and cover crops may result in less soil erosion than a more extensive system that does
not involve conservation techniques. Intensive land use can be combined with efficient soil conservation measures.

Further Eurostat information
Publications
Agriculture, fishery and forestry statistics — Main results – 2010-11 (http://ec.europa.eu/eurostat/product?code=KSFK-12-001&language=en) - 2012 edition
Environmental statistics and accounts in Europe (http://epp.eurostat.ec.europa.eu/portal/page/portal/product_details
/publication?p_product_code=KS-32-10-283) - 2010 edition
Farm data needed for agri-environmental reporting (http://epp.eurostat.ec.europa.eu/portal/page/portal/product_details
/publication?p_product_code=KS-RA-11-005)
Dedicated section
Agri-environmental indicators (aei) (http://epp.eurostat.ec.europa.eu/portal/page/portal/agri_environmental_indicators
/introduction)
Source data for tables, figures and maps (MS Excel)
Download Excel file
Other information
Commission Communication COM(2006) 508 (http://eur-lex.europa.eu/LexUriServ
/LexUriServ.do?uri=CELEX:52006DC0508:EN:NOT) - Development of agri-environmental indicators for monitoring the
integration of environmental concerns into the common agricultural policy
Commission Staff working document (http://epp.eurostat.ec.europa.eu/portal/page/portal/agri_environmental_indicators
/documents/workingpaperSEC(2006)1136.pdf) accompanying COM(2006)508 final
Corresponding IRENA Fact sheet: IRENA 23 (http://epp.eurostat.ec.europa.eu/portal/page/portal
/agri_environmental_indicators/documents/IRENA%20IFS%2023%20-%20Soil%20erosion_FINAL.pdf)

External links
Database:
European Soil Data Centre (ESDAC) (http://eusoils.jrc.ec.europa.eu/library/esdac/index.html)
European Environment Information and Observation Network (EIONET) (http://www.eionet.europa.eu/)
CORINE Land Cover 2006 (http://www.eea.europa.eu/data-and-maps/data/corine-land-cover-2006-raster)
Shuttle Radar Topography Mission (SRTM) (http://www2.jpl.nasa.gov/srtm/)
Other external links:
European Commission - Joint Research Centre (http://ec.europa.eu/dgs/jrc/index.cfm?id=10)
European Commission - DG Agriculture and Rural Development - Agri-environmental indicators
(http://ec.europa.eu/agriculture/envir/indicators/index_en.htm)
OECD - Agri-Environmental Indicators and Policies (http://www.oecd.org/topic
/0,3373,en_2649_33793_1_1_1_1_37401,00.html)

See also
Agri-environmental indicators (online publication)

References
1. Huber S., Prokop G., Arrouays D., Banko G., Bispo A., Jones R.J.A., Kibblewhite M.G., Lexer W., Möller A., Rickson

2.
3.
4.
5.
6.
7.
8.
9.

10.
11.
12.
13.

14.
15.

16.
17.

18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.

31.
32.
33.

34.

R.J., Shishkov T., Stephens M., Toth G., Van den Akker J.J.H., Varallyay G., Verheijen F.G.A., Jones A.R. (eds.):
Environmental Assessment of Soil for Monitoring: Volume I Indicators and Criteria. Office for the Official Publication of
the European Communities, Luxembourg, 339 pp. EUR 23490 EN/1. (2008)
Quinton J.N., Govers G., Van Oost K., Bardgett R.D.: The impact of agricultural soil erosion on biogeochemical cycling.
Nature Geoscience, April 2010, 311-314. DOI 10.1038 (2010)
Morgan R.P.C.: Soil Erosion and Conservation, 3rd edn. Blackwell Publ., Oxford. (2005)
EEA: Assessment and Reporting on Soil Erosion. EEA Technical Report 94. European Environment Agency. (2003)
Gobin A. and Govers G. (Eds.): Pan-European Soil Erosion Risk Assessment Project. Third Annual Report to the European
Commission. EC Contract No. QLK5-CT-1999-01323. (2003)
Poesen J., Torri D., Bunte K.: Effects of rock fragments on soil erosion by water at different spatial scales: a review.
Catena 23:141–166. (1994)
Schaub, D. and Prasuhn V.: A Map of Soil Erosion on Arable Land as a Planning Tool for Sustainable Land Use in
Switzerland. Advances in GeoEcology 31. (1998)
Bosco C., Rusco E., Montanarella L., Panagos P.: Soil erosion in the alpine area: risk assessment and climate change. Studi
Trent. Sci. Nat., 85, pp 119 – 125. Museo Tridentino di Scienze Naturali, Trento. (2009)
Renard K.G., Foster G.R., Weesies G.A., McCool D.K., Yoder D.C.: Predicting Soil Erosion by Water: A Guide to
Conservation Planning with the Revised Universal Soil Loss Equation (RUSLE). US Dept Agric., Agr. Research Service.
Agr. Handbook No. 703 (1997)
Iverson K.E.: Notation as a tool of thought. Comm. of the ACM 23, 444–465. (1980)
Quarteroni, A. and Saleri F.: Scientific Computing with MATLAB and Octave. Texts in Computational Science and
Engineering. Springer, Milan. (2006)
Wischmeier W.H.: A rainfall erosion index for a universal Soil-Loss Equation. Soil Sci. Soc. Amer. Proc. 23, 246–249.
(1959)
de Rigo D., and Bosco, C.: Architecture of a Pan-European Framework for Integrated Soil Water Erosion Assessment.
Environmental Software Systems. Frameworks of eEnvironment, IFIP Advances in Information and Communication
Technology, Volume 359, Chapter 34. (2011)
Haylock M.R., Hofstra N., Klein Tank A.M.G., Klok E.J., Jones P.D., New, M.: A European daily high-resolution gridded
dataset of surface temperature and precipitation. J. Geophys. Res (Atmospheres) 113, D20119. (2008)
Renard K.G., Foster G.R., Weesies G.A., McCool D.K., Yoder D.C.: Predicting Soil Erosion by Water: A Guide to
Conservation Planning with the Revised Universal Soil Loss Equation (RUSLE). US Dept Agric., Agr. Research Service.
Agr. Handbook No. 703 (1997)
Wischmeier W.H. and Smith D.D.: Predicting Rainfall Erosion Losses – A Guide to Conservation Planning. Agriculture
Handbook, No. 537, USDA, Washington DC. (1978)
Heineke H.J., Eckelmann W., Thomasson A.J., Jones R.J.A., Montanarella L., Buckley B.: Land Information Systems:
Developments for planning the sustainable use of land resources. Office for Official Publ. of the European Communities,
EUR 17729 EN. (1998)
Farr T., Rosen P., Caro E., Crippen R., Duren R., Hensley S., Kobrick M.: The Shuttle Radar Topography Mission. Reviews
of Geophysics 45, 33. (2005)
Morgan R.P.C.: Soil Erosion and Conservation, 3rd edn. Blackwell Publ., Oxford. (2005)
Šúri M., Cebecauer T., Hofierka J., Fulajtár, E.: Erosion Assessment of Slovakia at regional scale using GIS. Ecology 21(4),
404–422. (2002)
Cebecauer T. and Hofierka J.: The consequences of land-cover changes on soil erosion distribution in Slovakia.
Geomorphology 98, 187–198. (2008)
Bossard M., Feranec J., Otahel J.: CORINE land cover technical guide – Addendum 2000, Technical Report No 40,
European Environment Agency. (2000)
Casalegno S., Amatulli G., Bastrup-Birk A., Houston-Durrant T., Pekkarinen A.: Modelling and mapping the suitability of
European forest formations at 1km resolution. European Journal of Forest Research, Online First – 16 February. (2011)
Kempeneers P., Sedano F., Seebach L., Strobl P., San-Miguel-Ayanz J.: Data fusion of different spatial resolution remote
sensing images applied to forest type mapping. Submitted to IEEE Transactions on Geoscience and Remote Sensing. (2011)
JRC: Forest Type Map. Joint Research Centre. (2006)
Poesen J. and Lavee H.: Rock fragments in top soils: significance and processes. Catena 23: 1–28. (1994)
Poesen, J. and Ingelmo-Sanchez F.: Runoff and sediment yield from topsoils with different porosity as affected by rock
fragment cover and position. Catena, 19: 451-474. (1992)
Tetegan M., Nicoullaud B., Baize D., Bouthier A., Cousin I.: The contribution of rock fragments to the available water
content of stony soils: Proposition of new pedotransfer functions. Geoderma, 165 (1): 40-49. (2011)
Yaalon, D.H.: Soils in the Mediterranean Region: What makes them different? In: A.R. Mermut, D.H. Yaalon and S.
Clapp, C.E., Allmaras, R.R., Layese, M.F., Linden, D.R., Dowdy, R.H.: Soil organic carbon and carbon-13 abundance as
related to tillage, crop residue, and nitrogen fertilization under continuous corn management in Minnesota. Soil and Tillage
Research 55, 127-142. (2000)
Lasanta T., Beguería S., García-Ruiz J.: Geomorphic and hydrological effects of traditional shifting agriculture in a
Mediterranean mountain, Central Spanish Pyrenees. Mountain Res. Dev. 26:146–152. (2006)
Seeger M. and Ries J.: Soil degradation and soil surface process intensities on abandoned fields in Mediterranean mountain
environments. Land Degrad Devel 19:488–501. (2008)
García-Ruiz J.M., Lana-Renault N., Beguería S., Lasanta T., Regüés D., Nadal-Romero E., Serrano-Muela P., LópezMoreno J., Alvera B., Martí-Bono C., Alatorre LC.: From plot to regional scales: Interactions of slope and catchment
hydrological and geomorphic processes in the Spanish Pyrenees. Geomorphology 120:248–257. (2010)
Poesen J., Torri D., Bunte K.: Effects of rock fragments on soil erosion by water at different spatial scales: a review.

Catena 23:141–166. (1994)
35. Tricart J. and KiewietdeJonge C. Ecogeography and Rural Management – a Contribution to the International GeosphereBiosphere Programme. Longman Group, Harlow, UK. 267 pp. (1992)
36. Bielders C., Ramelot C., Persoons E.: Farmer perception of runoff and erosion and extent of flooding in the silt-loam belt
of the Belgian Walloon Region'. Environmental Science and Policy 6: 85–83. (2003)
37. Renard K.G., Foster G.R., Weesies G.A., McCool D.K., Yoder D.C.: Predicting Soil Erosion by Water: A Guide to
Conservation Planning with the Revised Universal Soil Loss Equation (RUSLE). US Dept Agric., Agr. Research Service.
Agr. Handbook No. 703 (1997)
38. Pretty J.N., Brett C., Gee D., Hine R.E., Mason C.F., Morison J.I.L., Rayment M., Bijl G., Van Der Dobbs T.: Policy and
practice. Policy challenges and priorities for internalizing the externalities of modern agriculture. Journal of Environmental
Planning and Management, 44: 263-283. (2001)

Retrieved from "http://epp.eurostat.ec.europa.eu/statistics_explained/index.php/Agri-environmental_indicator_-_soil_erosion"


Related documents


agrienvironmental indicator soil erosion
draft1 mca chapter gmes a baseline action plan pre ws
why invest wood pellets plant in east europe
02 antonio mendonca
8749 20grantstown 20nurseries 20case 20study 20final 20 002
7th icard 2006 abstract submission rayne and connell v1


Related keywords