1. Trends in Land Degradation in Europe
Luca Montanarella
EUROPEAN COMMISSION
JOINT RESEARCH CENTRE
Institute for Environment and Sustainability
TP 280
I Ispra (VA), Italy
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2. EU Thematic Strategy for Soil Protection adopted by the European Commission on the 22nd of September 2006
COMMUNICATION COM(2006) 231 on the Thematic Strategy for Soil Protection
DIRECTIVE COM(2006) 232 establishing a framework for the protection of soil and amending Directive 2004/35/EC
IMPACT ASSESSMENT SEC(2006) 620 of the Thematic Strategy for Soil Protection
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3. The impact of human activities on soil
Diffuse input of contaminants as particulates
Manures and fertilisers
Acids
Sewage sludge
Persistent substances
Pesticides & herbicides
Heavy metals
Gravel extraction
Accumulation/
Contamination
Gradual disappearance of farms
Soil erosion
Compaction
Release of toxic substances
Salinisation
Distruction of humus
Sealing
Acidification
Blocking of soil functions important to the ecology of the landscape
Destruction of soil
Gradual destruction of soils
Reduction in soil fertility
Changes in the structure of soils
Reduction in soil fertility
Contamination of soils and ground water with applied agrochemicals and atmospheric pollutants
Changes in soil composition
Adverse impacts on living organisms in the soil
Destruction of soil
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4. Threats to soil as identified in COM(2002) 179
Erosion
Decline in organic matter
Soil contamination
Soil sealing
Soil compaction
Decline in soil biodiversity
Salinisation
Floods and landslides
The EC communication “Towards a Thematic Strategy for Soil Protection” COM (2002) 179 identifies 8 major threats to soils functionality in Europe: soil erosion, decline in organic matter, soil contamination (both local and diffuse), soil sealing, soil compaction, decline in soil biodiversity, salinisation and floods and landslides. The communication highlights for each of these threats the current status, trend and impact. Throughout the communication the major problem identified is the dramatic lack of policy relevant information on these threats in Europe. Information is generally scarce, fragmented, unreliable and generally not comparable between Member States. A somewhat better situation can be observed in the candidate countries, where a centralised economic system in the past has being actively promoting the collection of detailed soil information for planning purposes. Generally, a huge amount of scientific data have been collected so far by many different institutions in Europe (National soil surveys, Universities, Regional and Local authorities, etc.). While this information is often of high scientific value, it seldomly provides the necessary policy relevant information needed in order to design an effective soil protection strategy in Europe. We are still not capable to tell, for example, how many tonnes per hectare of soil a lost each year by erosion in Europe; what is the current concentration of soil organic carbon and how this concentration is changing over time; how many hectare per year of soil is sealed; etc… Future soil protection policies will only be effective if the extend and the evolution over time of soil degradation is known. Of course, for some of the threats, still basic research is needed in order to gain the necessary understanding of the underlying mechanisms. This is the case for soil biodiversity, where still only very little is known about the different species present in soils, with still many species probably still to be identified.
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5. PESERA Soil Erosion Risk Assessment
Similar approaches have been also applied to other threats to soils. Erosion, for example, is currently estimated in Europe by using advanced models, like the Pan-European Soil Erosion Risk Assessment (PESERA) model, that combine soil data from the European Soil Information System, with climate data, slope and relief data (Digital Terrain Models) and land cover data in order to get an estimate of the extent and intensity of erosion in Europe in tons per hectare per year of soil lost. As for organic carbon, these estimates need extensive validation before they can be used for policy making purposes.
Water erosion: 115 Million ha
Wind erosion: 42 Million ha
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6. Main human-induced driving forces
Soil disturbance e.g. ploughing up-and-down slopes
Removal of vegetative soil cover and/or hedgerows
Increased field size (open fields)
Abandonment of terraces
Late sowing of winter cereals
Overstocking
Poor crop management
Inappropriate use of heavy machinery, in agricultural and forestry practices, but also during construction works.
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7. Consequences of erosion
On-site effects
Loss of soil
Loss of soil fertility due to disrupted nutrient cycles
Restrictions on land use hindering future redevelopment and reducing the area of productive and valuable soil available for other activities (agricultural and forestry production, recreation etc.)
Land value depreciation
Off-site effects
Damage to infrastructures due to excessive sediment load
Diffuse pollution of surface water
Negative effects on aquatic ecosystems and thereby biodiversity
Reduced water retention capacity, hence higher flood risk
Human health problems due to dust and particles in the air
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8. Cost of soil erosion
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9. Organic matter decline
Topsoil Organic Carbon Content (30cm)
Model output
Aggregated results
Organic carbon content (%) in the surface horizon (0-30 cm) of soils
National Soil Organic Carbon stocks (0-30cm) in Gt
Organic matter decline
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10. Net rate of change in England & Wales = - 4.4 Mt yr-1
Estimated changes in carbon stocks across England & Wales (and UK) Bellamy et al., Nature 437, (2005)
Net rate of change in England & Wales = Mt yr-1
Net rate of change in UK ≈ x UK / E&W topsoil OC stock
≈ -13 Mt yr-1
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11. Soil organic carbon decline
Main human-induced driving forces
Conversion of grassland to arable land
Drainage of wetlands
Poor crop rotation and plant residue management such as burning crops residues
Accelerated mineralization due to management practices such as continued tillage
Deforestation
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12. Consequences of SOM decline
Release of greenhouse gases
Negative effects on biodiversity, including soil biodiversity
Reduced water infiltration due to changes in soil structure, hence higher flood risk
Reduced absorption of pollutants and increased water and air pollution
Increased erosion with the effects stated above such as:
Loss of fertile soil
Loss of soil fertility (i.a. due to disrupted nutrient cycles)
Damage to infrastructures due to excessive sediment load
Diffuse pollution of surface water
Negative effects on aquatic ecosystems and thereby biodiversity
Restrictions on land use and hindering future redevelopment and reducing the area of productive and valuable soil available for other activities (agricultural and forestry production, recreation etc.)
Land value depreciation
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13. Loss of Biodiversity in Soil
Consequences of biodiversity decline
Reduced food web functioning and consequently crop yield losses
Reduced soil formation
Reduced nutrient cycling and nitrogen fixation
Reduced carbon sequestration
Reduced resilience of the soil to endure pressures
Reduced recycling of organic waste/litter
Increased plant pests and diseases
Reduced water infiltration rate and water holding capacity
Reduced bioremediation capacity
Hampered soil structure (by affecting the stabilisation of organo-mineral complexes)
Reduced genetic resources present in the soil, including moral and ethical consequences
Negative impacts on terrestrial biodiversity outside of soil
Fungy
(35000)
Nematodes
(5000)
Protozoa
(1500)
Algae (2500)
Bacteria
(3200)
Acari
(25000)
Others (6200)
Collembolla
(6500)
Number of known species in soil
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14. Soil Salinisation in Europe
Salinisation affects around 3.8 million ha in Europe
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15. Main human-induced driving forces for salinisation
Poor irrigation technology
Inappropriate drainage
Use of saline waters for irrigation and the overexploitation of groundwater
Consequences of salinisation
On-site effects
Loss of soil fertility due to toxic effects of high salt content
Loss of biodiversity
Land value depreciation
Off-site effects
Reduced water infiltration and retention resulting in increased water run-off
Damage to transport infrastructure from shallow saline groundwater
Damage to water supply infrastructure
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16. Cost of Soil Salinisation in Europe
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17. Main human induced driving forces
Soil contamination
Main human induced driving forces
Industrial installations
Mining installations
Illegal waste dumps and landfill sites not properly managed
Storage of chemicals
Accidental and provoked spills of chemicals
Atmospheric depositions of dangerous substances
Military sites
Intentional introduction of dangerous substances in the soil
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18. Consequences of soil contamination
Risk to human health for people living on and in the surroundings of a contaminated site (through different exposure paths, e.g. consumption of food grown in from contaminated areas)
Contamination of surface water, mainly through run off of contaminated sediments
Contamination of groundwater and hence drinking water if extracted from groundwater
Risk to human health through drinking water extracted underneath of a contaminated site
Risk of ecotoxicity for the flora and fauna living in the soil on the site and around a contaminated site causing loss of biodiversity and biological activity
Loss of soil fertility due to disrupted nutrient cycles
Restrictions on land use and hindering future redevelopment and reducing the area of productive and valuable soil available for other activities (agricultural and forestry production, recreation etc.)
Land value depreciation
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19. The Cost of Soil Contamination
Estimated total annual cost caused by soil contamination for EU25 (€ M, 2003)
On-site costs
Off-site costs
Total
Lower bound estimate 96
2,283
2,379
Intermediate estimate
192
17,126
17,318
Upper bound estimate
289
207,615
207,904
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20. Soil Compaction in Europe
36% of European Soils are having high or very high susceptibility to compaction
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21. Source: R. Horn, personal communication
Soils in Europe can support different loads depending on their soil strength
Source: R. Horn, personal communication
Precompression stress at a given pore water pressure pF 1.8 for topsoils of Europe in relation to a given low topsoil load (tyre inflation pressure: 60 kPa), high topsoil stress: 200 kPa)
Classification of the effective soil strength by the relationship of precompression stress to soil pressure: >1.5 very stable, elastic deformation, stable, labile, >0.8 unstable, additional plastic deformation.
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22. The Impact of Soil Compaction in Europe
Damage due to increasing soil deformation
After rain storm
Rapid water table increase in rivers and lakes
Reduced groundwater recharge
erosion
N2O gas
emission
N - loss due to stagnic water
Effects on the environment
Surface water runoff increase
Heavy machinery compacts arable, forest, and pasture soils
Consequences for plant production
Reduced growth, higher uncertainty less yield
Increased fungi deseases,
more weeds
Reduced root growth (less dense and deep)
Soil biota suffers
Soil quality declines due to reduced pore volume, - reduced aeration
Water infiltration reduced,
- soils remain longer wet and cold, more slaking problems, reduced water storage
Effects on soil management
- higher draft energy required, - higher fuel consumption, - wet and cold soils result in smaller number of working days, - more fertilizers needed
Dust emission increased
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Source: R. Horn, personal communication

23. Soil Sealing by Infrastructure and Housing
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24. The Impact of Soil Sealing
Main human driving forces for sealing
Urban sprawl
Increased transport
Movement of population
Consequences of sealing
Disruption of gas, water and energy fluxes
Increased flood risks
Reduced groundwater recharge
Increases water pollution (due to runoff water from housing and traffic areas being normally unfiltered and potentially contaminated with harmful chemicals)
Loss in soil and terrestrial biodiversity (due to fragmentation of habitats)
The Impact of Soil Sealing
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25. Landslides
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26. Main human-induced driving forces for landslides
Rupture of topography such as due to construction works
Land use changes such as deforestation and land abandonment
Extractions of materials
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27. The Cost of Landslides in Europe
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28. Conclusions
Extensive soil and land degradation processes are occurring in Europe.
Observed degradation processes are mostly human induced.
Extreme climatic events may further exacerbate the impact of the land degradation on local population.
The total costs of soil degradation that could be assessed for erosion, organic matter decline, salinisation, landslides and contamination on the basis of available data, would be up to €38 billion annually for EU25.
The recently adopted Soil Thematic Strategy by the European Commission provides the legal framework for EU Member States to implement adequate responses in order to revert the negative trend of land and soil degradation in Europe.
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29. Desertification and Climate Change
Preliminary announcement
Wengen-2007 International and Interdisciplinary Workshop
Desertification and Climate Change
Hotel Regina, Wengen, Switzerland, September 10-14, 2007
Co-organized by:
Michel Verstraete, Andreas Brink and Luca Montanarella
European Commission, Joint Research Centre, Institute for Environment and Sustainability, Ispra, Italy
Bob Scholes
Council of Scientific and Industrial Research, South Africa
&
Martin Beniston
Universities of Geneva and Fribourg, Switzerland
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30. Thank you for your interest!
“Unity in diversity”
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