Erosion, biodiversity, contamination and the declining state of soil in Europe

Introduction

Soil is a habitat and gene pool, serves as a platform for human activities, landscape and heritage, and acts as a provider of raw materials. A healthy, fertile soil is at the heart of food security. These functions are worthy of protection because of their socio‐economic as well as environmental importance.

Current information suggests that, over recent decades, soil degradation has increased and will increase further if no action is taken. Soil degradation is driven or exacerbated by human activity and projected climate change, together with individual extreme weather events which are becoming more frequent, is likely to have also negative effects on soil.

Eight major aspects of soil degradation in Europe have been identified including biodiversity decline, contamination, erosion and organic matter decline.

All these problems have considerable economic and environmental consequences and could eventually compromise food production. In this context, the JRC's European Soil Bureau Network has therefore established a Working Group on Public Awareness and Educational Initiatives for Soil.

What are the key drivers of soil degradation in Europe?

Soil is one of the planet’s invaluable resources but continues to be degraded in Europe. Together, the mineral particles, water, air, organic matter, and living organisms that constitute soil perform key functions which underpin our society.

Soil is by far the most biologically diverse part of Earth. Soil biota play many fundamental roles in delivering key ecosystem goods and services.

The 8 main major aspects identified in the report as drivers of soil degradation are:

• Biodiversity decline, induced by soil contamination, erosion, salinisation and sealing; Soil biodiversity reflects the mix of living organisms in the soil. These organisms interact with one another and with plants and small animals forming a web of biological activity.
• Soil compaction induced by machinery use leads to a reduction in biological activity, porosity and permeability. It reduces water storage and conduct and make soil less permeable to plant roots, can affect water infiltration capacity and increase erosion risk by accelerating run‐off.
• Contamination which, after 200 years of industrialisation, is a widespread problem in Europe : about 3 million sites where potentially polluting activities are occurring, or have taken place in the past while In recent years, around 80 000 sites have already been treated while many industrial plants have attempted to change their production processes to generate less waste. It is important to distinguish between local soil contamination (the result of intensive industrial activities or waste disposal and diffuse soil contamination covering large areas (associated in part to agrochemicals), the most frequent contaminants being heavy metals and mineral oil;
• Erosion by wind or water with about 16% of total land area in Europe (except Russia) affected in the nineties;
• Land slides triggered by land abandonment and land-use change, more frequently in areas with erodible soils or clay-based sub-soils;
• Loss of organic matter, an issue driven mainly by inappropriate management of irrigated agricultural soil. About 45% of soils in Europe, says the report, content only between 0 and 2% of organic carbon, particularly in the southern Europe but also in the UK, Germany Norway and Belgium;
• Salinisation and acidification which is mainly originating from irrigation water and fertilizers;
• Soil sealing, when agricultural or non-developed land is used for urban sprawl, industrial development or transport infrastructure. Soil sealing causes adverse effects on, or complete loss of, soil functions and prevents soil from fulfilling important ecological functions. Fluxes of gas, water and energy are reduced, affecting, for example, soil biodiversity. The water retention capacity and groundwater recharge of soil are reduced, resulting in several negative impacts such as a higher risk of floods.

Are there other potentials threaths to soil integrity?

Desertification or biofuels production and acidification are other potential threats to soil integrity considered in this report.

• The recognition of desertification appears in the Mediterranean region as, together with the hot, dry climate of the region, many soil types already exhibit many aspects of degradation ,i.e. low SOC content, prone to erosion, low fertility.
• Acidification leads to substantial damage of watercourses and lakes through the lowering of pH and increased aluminium concentrations which can affect aquatic life, groundwater and the related drinking water supply. It is a process which is naturally irreversible when compared to human lifespans.
• Regarding biofuels , there are concerns that increasing their production may lead to inappropriate land management practices and increased levels of soil degradation. On a global level, a high biofuel demand may result in competition between biofuel and food production. To assess the impact of land use changes due to biofuel production, the JRC has developed guidelines to quantify changes in the amount of organic carbon in soils and biomass. This is an important factor in the sustainability assessment. The guidelines follow the Intergovernmental Panel on Climate Change (IPCC) guidelines for national greenhouse gas inventories and are supported by comprehensive global data processed by the JRC.

What are the main causes of soil degradation?

Widespread soil degradation, leading to a decline in the ability of soil to carry out its ecosystem services, is caused largely by non‐sustainable uses of the land. Poor land management, such as deforestation, overgrazing, construction activities and forest fires are among the main causes of this situation.

This has marked local, regional, European and global impacts. Soil degradation contributes to food shortages, higher commodity prices, desertification and ecosystem destruction.

What is the relationship between soil degradation and climate change?

Climate change also may worsen soil degradation, underlines the report, related to more frequent and more severe droughts. Other than in tropical ecosystems, soil contains about twice as much organic carbon as above‐ground vegetation. There is growing realisation of the role of soil, in particular peat, as a store of carbon and its role in managing terrestrial fluxes of atmospheric carbon dioxide (CO₂).

While climate is a key soil forming factor and governs a large number of pedogenic processes, soil can also influence global climate. Soils in the northern latitudes store huge amounts of organic carbon, much of which is affected by permafrost and permanently or seasonally frozen. Currently, around 500 Gt of carbon is stored in permafrost‐affected soil in the northern circumpolar region. Large releases of greenhouse gases from these could have a dramatic effect on global climate, although the exact relation is complex and requires additional research.

Unless suitable land management procedures are implemented, increased and more severe droughts will cause soil water retention mechanisms to collapse, leading to the onset of erosion, desertification and increased risk of flooding.

Can soil degradation have an impact on human health?

Poor soil quality can affect human health in several ways, leading to specific diseases or general illness. Pathogens (such as tetanus), parasites (e.g. hookworm) and concentrations of toxic elements (e.g. aluminium, arsenic, cadmium, copper) in the soil can lead to a decline in general health. However, many of the relationships between soil and health are unclear and require further research.

What are the costs associated to soil degradation?

Evidence shows that the majority of the costs are borne by society in the form of damage to infrastructures due to sediment runoff and landslides, increased healthcare needs for people affected by contamination, treatment of water contaminated through the soil, disposal of sediments, depreciation of land around contaminated sites, increased food safety controls, and costs related to the ecosystem functions of soil.

Is the EU playing a role in its soil protection?

Quantitative assessments of future trends in soil characteristics and properties are limited. At the difference of the numerous policies and legislations regarding water, air, waste, chemicals, industrial pollution, nature protection, pesticides and agriculture, there is no specific EU legislation specifically targeting the protection of soil.

In response to this situation, the EU Commission adopted in 2006 a Thematic Strategy which aims at taking into account the full range of threats and ensuring that EU soils stay healthy for future generations. The strategy encompass a common and comprehensive approach to soil protection focusing on soil functions structured along three lines : identification of the problem, preventive and operational measures oriented towards each of the 8 main threats identified. A key pillar of this Strategy is targeted research that aim to ensure the sustainable use of soil.

The JRC report undelines that the Common Agricultural Policy has a key role to play a.o. by encouraging farming practices that maintain soil fertility. Another pillar of the Soil Thematic strategy is targeted research to develop the kowledge base underpinning policies and necessary to tackle the issue : Biosoil, EcoFINDER, ENVASSO, geoland2, RAMsoil and many other projects. The focus is placed in particular on the identification of the appropriate indicators of soil integrity. Ine ENVASSO project, for example identified a set of 27 priority indicators, with baseline and threshold values, that could be rigorously defined and implemented relatively easily to form a Europewide reference base that could be used to assess current and future soil status.

On the other hand, within the roadmap aimed at transforming Europe's economy into a sustainable one by 2050 , soil is identified as a key natural resource, with particular focus on food security and water management (both floods and drought).

Meanwhile, the European Commission Thematic Strategy noted a marked lack of awareness on the importance of soil and the need of soil protection an stressed the need for measures to improve knowledge and exchange of information on best practices to fill this gap.

Was a EU Regulation on soil protection against degradation eventually adopted?

No. Some five years after the adoption of this Soil Thematic Strategy, the European Commission published a policy report on the implementation of the Strategy and ongoing activities (COM(2012) 46 ) but, taking note that the proposal has been pending for almost eight years without a qualified majority in the Council in its favour, the Commission in April 2014 took the decision to withdraw the proposal for a Soil Framework Directive¹. Among other reasons, a majority of Member States supporting the proposal, a number of countries argue that soil degradation does not have transboundary consequences and thus soil legislation should be a matter of national competence only (the principle of subsidiarity). The Directorate General for Environment of the European Commission organised an EU Soil stakeholders' conference in Brussels on 5th December 2016 with the objective to present the inventory of soil-related legislation at EU and national level and gap analysis².

¹ See: http://ec.europa.eu/environment/soil/process_en.htm 
² http://ec.europa.eu/environment/soil/public_events_en.htm