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Farmers & Forestry

RECARE-Hub contains the latest information on preventing soil threats, and cost-benefit analysis on proven remediation techniques.

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Discover innovative sustainable land management measures that can combat threats to key soil functions.

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Find out more about land care strategies relevant to your region and our integrated assessment of existing soil related policy.

Researchers

Access a wealth of European research data on soil threats and the efficacy of land care strategies.

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Whether you're a teacher or a concerned environmentalist, find out why Europe's soils are under threat and what researchers are doing to help combat the problems.

Resources designed for you

 

The soil that underpins Europe's agricultural systems faces numerous threats.

If you are interested in learning about specific soil threats, you can explore the individual threats below. If you want detailed guidance for assessing soil degradation or learning about management measures to prevent and remediate against soil degradation, you might want to head straight over to RECARE's resources.

 

RESOURCES

Case Study Experiment - reduction in contamination through amendment additions and afforestation

The researchers tested and monitored the efectiveness and duration of amendments to reduce contamination in the Guadiamar corridor.  They also monitored the effects of trees on soil contamination and carbon sequestration.

Amendments
Reduction of contamination by amendment addition

 

Afforestation
Afforestation of contaminated land

Final Results

  • The main target was to increase pH and thereby reduce the availability of cationic trace elements.

  • The addition of amendments increased pH and their effects lasted with time. Sugar beet lime increased pH by 111%, while biosolid compost increment was 43%.

  • The available concentration of trace elements showed a strong decrease in the amended plots. In particular, sugar beet lime reduced Cd, Cu and Zn availability by 99%.

  • The soil pH under trees ranged from 2.6 up to 6.1 and was negatively and exponentially related with availability of trace elements (see example of Cd in the figure below).

Figure 2 soilpH

  • Ceratonia, Fraxinus, and Populus were the tree species most effective at reducing trace elements availability in the soil underneath them.

Enrichment of soil organic carbon was a second target of remediation measures.

  • The initial values of soil carbon were very low, around 1%. The addition of biosolid compost doubled soil carbon.
  • Soils underneath trees were richer in organic carbon than those in the treeless sites. The highest values were for Ceratonia and Fraxinus.

Further details about this experiment can be found in the fact sheet HERE (ES) and in the project report HERE.

For more details about this experiment, please contact Teodoro Marañón This email address is being protected from spambots. You need JavaScript enabled to view it.

Scientific articles

Madejón, Paula, María T. Domínguez, Engracia Madejón, Francisco Cabrera, Teodoro Marañón, and José M. Murillo. Soil-plant relationships and contamination by trace elements: A review of twenty years of experimentation and monitoring after the Aznalcóllar (SW Spain) mine accident. Science of The Total Environment 625 (2018): 50-63.  doi.org/10.1016/j.scitotenv.2017.12.277doi.org/10.1016/j.scitotenv.2017.12.277

M.T. Domínguez,J.M. Alegre, P. Madejón, E. Madejón, P. Burgos, F. Cabrera, T. Marañón, J.M. Murillo (2016) River banks and channels as hotspots of soil pollution after large-scale remediation of a river basin  Geoderma Vol 261, 1 January 2016, Pages 133–140 DOI:10.1016/j.geoderma.2015.07.008

María T. Domínguez, , Ignacio M. Pérez-Ramos, José M. Murillo, Teodoro Marañón Facilitating the afforestation of Mediterranean polluted soils by nurse shrubs.Journal of Environmental Management Vol Volume 161, 15 September 2015, Pages 276–286 doi:10.1016/j.jenvman.2015.07.009

María Anaya-Romero,Sameh Kotb Abd-Elmabod, Miriam Muñoz-Rojas, Gianni Castellano, Carlos Juan Ceacero, Susana Alvarez, Miguel Méndez, Diego De la Rosa (2015) Evaluating Soil Threats Under Climate Change Scenarios in the Andalusia Region, Southern Spain. Published in: Land Degradation & Development Volume 26, Issue 5 July 2015 Pages 441–449 http://onlinelibrary.wiley.com/doi/10.1002/ldr.2363/full

For more details about this experiment, please contact Teodoro Marañón This email address is being protected from spambots. You need JavaScript enabled to view it.

Geographical location

The study area is located in southern Spain (see below). It was declared the "Protected Landscape Guadiamar Green Corridor" on April 2003, occupying about 2,700 ha. It is 60 km long, following the Guadiamar River, and 0.5–1.1 km wide connecting the Sierra Morena Mountains and the coastal Doñana Park, and crossing extensive agricultural and rural lands (Fig. 1). The climate is typically Mediterranean, with mild rainy winters (about 500 mm mean annual rainfall) and hot, dry summers. The mean annual daily temperature is about 17ºC, with a maximum temperature of 33.5ºC in July and a minimum temperature of 5.2ºC in January. The predominant soils in the area belong to the great groups Xerofluvent, Xerochrept, Haploxeralf and Rhodoxeralf.

fig151 Location and Digital Elevation Model (DEM) of the Guadiamar Case Study (Source: SRTM)

Main soil threat

GuadiamarLandscape

The main threat in the Guadiamar valley is soil contamination after a mine spill occurred on April 1998. About four hm3 of acid waters and two hm3 of mud, rich in heavy metals, were released into the Agrio and Guadiamar rivers affecting more than 4,600 ha of agricultural and pasture land (see Grimalt & Macpherson, 1999). Main trace- elements contaminating soil and water were As, Cd, Cu, Pb, Tl and Zn (Cabrera et al. in Grimalt & Macpherson, 1999). The area was subjected to a large-scale phyto-management project, including the removal of sludge and topsoil, the addition of amendments, and plantation of native shrubs and trees, and consequently protected as the "Guadiamar Green Corridor". The total cost of the remediation program, including the purchase of the land, rose up to €165 million paid by public funds (Arenas et al. 2003). While concentrations of available As and Pb in soil and plants have decreased over time, the levels of Cd and Zn in poplar leaves (used as bio-indicators) are still relatively high (Madejón et al. 2013). Long-term monitoring of the potential toxicity of residual contamination, in particular of Cd, is needed. Main constraints and challenges include among others the need for harmonization of soil contamination threshold levels and indicators, the need for new experiments on remediation measures and evaluation of their stability and longevity, development of new materials for remediation, to develop adaptive management programs, and to transfer technologies for diagnosis, monitoring and restoring contaminated soils.

Other soil threats

Other soil threats in Guadiamar include: 1) Floods that are relatively frequent after strong rains, eroding river banks, moving sediments and submersing vegetation in the floodplain; 2) Soil erosion by water where river banks have poor vegetation cover; 3) Desertification potential: the typical Mediterranean summer drought is a source of biological stress that combined with heavy metal stress could result in desertification at local scale; 4) Loss of organic matte due to accelerated mineralization of organic matter during the summer (frequently over 40oC); 5) Loss of soil biodiversity due to soil contamination by toxic elements and very low pH.

Natural Environment

Geology and soils
The Aznalcóllar mining district is located on the south-eastern edge of the Iberian Pyrite Belt (IPB). The IPB constitutes the largest and most important volcanogenic massive sulfide province in W Europe. It extends 200 km from SW Portugal to the W of Sevilla in Spain. Geologically, the mine area is situated on the northern edge of the Guadalquivir Tertiary basin, where transgressive Miocene sediments cover Paleozoic materials. The lower course of the Guadiamar River is underlain by Miocene blue marls and yellowish calcareous sandy silt, although most of the flood-plain is carved on Pleistocene alluvial terraces and Holocene deposits. The mining tailings reservoir was located on the Miocene blue marls of this lower course. On this geological context, the alluvial sediments of the Guadiamar and southern marsh deposits within the coastal wetlands of the Guadalquivir were directly affected by the pyritic sludge. The alluvial deposits of the Guadiamar fluvial system consist of silt, sand and gravel. Gravels are dominant, though quartz sands are locally abundant. Three terrace levels can be recognized along the affected valley segment. The high terrace is preserved only in the northern area, near the confluence of the Agrio and the Guadiamar rivers, whereas it is totally eroded to the south (Gallart et al., 1999 and López-Pamo et al., 1999). The soils in the study area correspond to the Mediterranean edaphic zone, which is very heterogeneous due to a highly variable lithology and mesoclimate. A survey of the affected area up to the Marismas at scale 1:20,000 showed that the alluvial soils are calcareous and non-calcareous typic and aquic Xerofluvents (FAO, Fluvisols), with sandy and sandy-loam textures. Soils of the lower terraces are typic and aquic Haploxerlfs (FAO, Luvisols) and Aquic Xerofluvents (FAO, Fluvisols), while in the higher terraces appears typic Rhodoxeralf soils (FAO, Luvisols) associated to sandy soils and pseudogley. In the contact of terrace and alluvial there are soils of erosion classified as Calcixerollic Xerochreps (FAO, Calcisols) (Clemente et al., 2000; Nagel et al., 2003).

fig152

Left: Soil map of (Source: JRC) and land use map (Source: CORINE) of the Case Study.

Land Use

Previous to the mine accident, the Guadiamar Valley was mainly occupied by croplands (sunflower, fruit orchards) and pasture lands. After the spill-contamination and the expropriation, the total area of 2,706.8 ha was declared as the “Protected Landscape of Guadiamar Green Corridor” (April 2003) and was relieved of agriculture and livestock use. Soils have been remediated and the land afforested with native shrub and tree species (Domínguez et al., 2010). Currently, the main land use is for the conservation of biodiversity and the establishment of an ecological corridor connecting the Doñana National park (to the south) and the Sierra Morena Mountains (to the north). Another important land use is currently recreation, mainly cycling, trekking and horse-riding along two main tracks running parallel to the river. Environmental education and touristic activities are also organized in the Information Center of Aznalcázar (www.guadiamareduca.com).

Horse grazing is an activity being considered for the current land use at the Green Corridor. The presence of horses in this protected area was initially triggered by the pressure exerted by the surrounding municipalities for using pastures, despite the fact that grazing was initially forbidden after the accident. Due to this pressure, the option of horse grazing (livestock not intended for human consumption) was considered by the Regional Government as a benign and sustainable management tool for control of the herbaceous cover. At present, control of the horses is carried out by “Equine Guadiamar Society”. One of the disadvantages of this practice is that vigorous and healthy herbaceous cover competes with planted woody species for water and nutrients, and its desiccated remains present a fire hazard during summer droughts. Also, mechanical control of herbaceous species is expensive, may affect biodiversity and generates greenhouse gas emissions. At present, all horses grazing in the corridor must be obligatory identified (marked by plaques) but their presence is still considered illegal. Nevertheless, pasture evaluation has eliminated the possibility of acute toxicity for horse grazing (Madejón et al., 2009b; 2012).

fig153

Horses grazing in the Guadiamar Green Corridor. In the background the mounds of the Aznalcóllar mine. Photo by J.M. Murillo.

Climate

The climate is typically Mediterranean, with mild rainy winters (about 500 mm mean annual rainfall) and hot and dry summers. The mean annual daily temperature is about 17oC, with a maximum temperature of 33.5oC in July and a minimum temperature of 5.2 oC in January-see below.

fig154

Left: Average annual; right: mean monthly precipitation and temperature at Guadiamar

Hydrogeology

The main tributary to the Guadiamar River is the Agrio River, where the mine spill occurred. The catchment area supplying the Agrio dam is 228 km2 and the mean annual runoff volume is 44.7 hm3. The total catchment area of the Guadiamar is 1,879 km2, the annual flow volume is 209 hm3, and the mean flow rate is 6.6 m3s-1 (Aznalcázar gauging station), nevertheless with a high interannual irregularity. The higher flow period is from January to March (mean rate of 13 m3s-1) and the lower from June to October (3 m3s-1) (Gallart et al., 1999).According to their geomorphic characteristics and human impacts, three main sectors can be distinguished: (a) Along the first 15 km downstream of the tailings reservoir, is a suspended load and sand and gravel bed load river; (b) Between 15 and 30 km downstream of the tailings reservoir, with a much lower valley gradient, is a river dominated by pebble and sand textures with smaller peak discharges than those of the former reach. The floodplain (300-700 m) shows multiple low sinuosity flood channels forming a branching pattern of channels, which are active during flood stages once the floodwaters overtop the natural levees. (c) The lowest reach (from “Vado del Quema” to Doñana marshes) is a suspended load river reach with fine sand and silt textures, and a stream gradient similar to or lower than that of the previous reach. The natural fluvial system in this area was drastically changed during the late 1950s to allow farming. This final reach presents a gentler gradient downstream from the “Vado del Quema” area where marsh sediment is dominant, partially covered by aeolian deposits (Gallart et al., 1999).

Drivers and pressures

The increasing demand for metals for industrial production is one of the main drivers promoting mine activities and the consequent environment impact. The Guadiamar River originates in the south-eastern edge of the Iberian Pyrite Belt, a volcanic-sedimentary complex which has been exploited for gold, silver and copper ore from pre-Roman times (more than 2000 years ago) (López-Pamo et al., 1999). The mine activity in Aznalcóllar produced a diffuse contamination of heavy metals in the Guadiamar River, already detected before the 1998 accident (Cabrera et al., 1987). In a survey of European contaminated sites (about 342,000 sites) the second source of contamination was the industrial/commercial sector, including mining activities, and the heavy metals represented the first type of contaminant (in 35% of sites) (Panagos et al., 2013). After the mining accident and consequent contamination of land, the area was declared Protected Landscape of the Guadiamar Green Corridor and devoted to conservation and recreation. Currently main pressures and threats are: contamination by industrial and urban wastes (there are 7 sewage treatment plants connected to the river); water extraction for agricultural and industrial use; obstruction of the ecological connectivity within the corridor by urbanization, industrial tree plantations and croplands; fire and overgrazing (sometimes despite being forbidden); and the uncertainty of reopening the Aznalcóllar mine and its future impact (JA, 2014)

Status of soil threat

Few days after the mine accident, Cabrera et al. (1999) analysed total heavy metal concentrations in soil samples of seven selected areas along the Guadiamar River valley affected by the toxic flood after removal of the deposited sludge. They reported that the total concentrations of the elements As, Au, Bi, Cd, Cu, Pb, Sb, Tl and Zn were higher in sludge-covered soils than in unaffected soils, with increases into the range of 6 times for Au and 370 times for Sb. After remediation measures, Hg and the other trace-element contents in soils were still higher than background values, and occasionally higher than values before restoration (Cabrera et al., 2008) with an increase of 10 times for Hg. The increase of other trace elements was into the range of 5 times for Cu and 8.4 times for As and Pb. This was attributed to remains of sludge left on the soil surface and buried during restoration operations (sludge removal, liming, and manuring). Total trace-element concentrations were highly variable, indicating a patchy and irregular distribution of the trace elements on the surface soils along the Guadiamar river basin (Cabrera et al., 2008). Nevertheless, further monitoring in 2005 (Domínguez et al., 2008) reported that despite the high concentrations of several trace elements in the affected soils there was a limited transfer of these elements to the aboveground parts of woody plants. This seemed to indicate a reasonable trace element stabilization in soils although the authors highlighted that soil pH requires close monitoring, since acidification will result in increased trace element mobility and it may increase the rates of leaching into receiving waters. Domínguez et al. (2009) and Ciadamidaro et al. (2014) remarked that soil pH is the most important factor affecting the soil contamination and quality.

 

 fig155

 Upper left: Dam of the Aznalcóllar tailings pond that was broken on 25 April 1998,
releasing the contaminating content (Photo: Junta de Andalucía);
upper right: remains of mine sludge in soils of the river banks, 16 years after the spill.
Bottom: a detail of the soil auger showing the layer of sludge over the soil. Photos by J.M. Murillo.

 

A recent study (Burgos et al., 2013) has demonstrated the effectiveness of the remediation tasks carried out in all the area for this trace elements stabilization which avoided the leaching of the most mobile elements and minimized the risk of contamination of groundwater sources, many of them close to the Doñana National Park. In a recent survey of the river banks and the margins of the floodplain in the Guadiamar area, a high contamination of soil with trace elements has been detected, mainly in the northern part of the area; that is from the mine Aznalcóllar to Sanlúcar la Mayor (Alegre 2014). In this area the acidity (low pH) of the soils may aggravate the problems of toxicity for plants and animals. The results also show that in the survey of contamination within a river basin, most of the sampling is focused on the floodplain (normally with high-valued agricultural use). However, the problem of contamination may persist on river banks and levees, less accessible to clean up and remediation practices, and also more sensitive due to their proximity to the water flow. In the banks of the north part of the studied area, the concentration of S (one of the most representative constituent of the sludge) can reach values as high as 9 % (mean of 2.4 %), far greater than those values in the floodplain (mean of 0.3 %).

WOCAT Maps 

Maps on the current state of land use, soil degradation and soil conservation in the case study area have been produced using the WOCAT (World Overview of Conservation Approaches and Technologies) methodology

The steps of this process are as follows:

1) The area to be mapped is divided into distinctive land use systems (LUS).
2) The team gathers the necessary data on soil degradation and conservation for each LUS using a standardised questionnaire, in close consultation with local land users, and supported where possible by remote sensing or field data.
3) For each LUS, the soil degradation type, extent, degree, impact on ecosystem services, direct and indirect causes of degradation, as well as all soil conservation practices, are determined.
4) Once collected, the data is entered in the on-line WOCAT-QM Mapping Database from which various maps can be generated.

Following the principles of all WOCAT questionnaires, the collected data are largely qualitative, based on expert opinion and consultation of land users. This allows a rapid and broad spatial assessment of soil degradation and conservation/SLM, including information on the causes and impacts of degradation and soil conservation on ecosystem services.

More details about the methodology used to produce these maps and their interpretation can be found here.

Land Use (click on maps to expand)

Spain Guadiamar land use types Spain Guadiamar area trend land use systemS Spain Guadiamar trend in land use intensityS

Soil Degradation

The degree of degradation reflects the intensity of the degradation process, whilst the rate of degradation indicates the trend of degradation over a recent period of time (approximately 10 years).

Spain Guadiamar dominant types of soil degradationS Spain Guadiamar degree of degradationS Spain Guadiamar rate of degradationS

Conservation Measures

The "effectiveness" of conservation is defined in terms of how much it reduces the degree of degradation, or how well it is preventing degradation. The Effectiveness trend indicates whether over time a technology has increased in effectiveness.

Spain Guadiamar dominant conservation measures Spain Guadiamar effectiveness of conservation measures Spain Guadiamar conservation effectiveness trends

Effects of soil threat on soil functions

The soil contamination affects several functions and therefore the ecosystem services provided (see summary following table).

Function of soilExplanationEffect
Biomass production Trace element toxicity reduces plant growth and biomass production. M
Environmental interactions

The toxicity of elements such as Cd, As, Pb and Tl for plant, animals and microorganisms is the worst effect for the environment.

Potential higher bioavailability of metals through decreasing pH.

Potential diffusion of metals through fluvial erosion.

H

Gene reservoir/

Biodiversity pool

Soil contamination and reduced pH may reduce biodiversity eliminating low-tolerant species. The effects on soil biota are not well known. L
Physical medium Base for built development is not affected N
Source of raw materials Although raw material collection is not affected directly, logging and gravel extraction have been forbidden in the area. L
Carbon pool Indirectly, the afforestation of former agricultural land has increased the C stocks in soils. L
Cultural heritage Indirectly, the contamination event and posterior recuperation has increased the cultural value of the site. M

Summary of the effects of soil contamination on the soil functions for the Guadiamar site. The ranking (N: None; L: Low; M: Medium; H: High) is expressed in the right column.

Administrative and socio-economic setting

The mine of Azanalcóllar is located in an economically deprived area and it was the main employer in the zone. At the time of the accident, it employed about 400 persons and permitted the employment of 1,800 persons indirectly. As a consequence of the accident, in 1999 the Regional Government and the Central Administration have launched two important restoration programmes: The Guadiamar Green Corridor and the Doñana 2005 Plans. The Guadimar Green Corridor promoted and funded by the Andalusian Regional Government, aims at the restoration of the Guadiamar basin and the reestablishment of an ecological corridor between the mountains area of Sierra Morena and the litoral systems of Doñana. At the same time, the programme seeks the improvement of the quality of life of the Guadiamar basin inhabitants, by developing a socio-economical system that is environmentally sustainable and integrated in the natural context. The programme has received the support of the American Agency for Environmental Protection, the European Council, the International Union for Conservation of Nature, the Environmental European Agency and Conservation of Nature, the Environmental European Agency and conservation NGOs, due to its integrated and scientifically sound approach and to the importance given to the public participation for the achievement of the programme objectives (Bartolomé and Vega, 2002).

Main institutional players in the study site are the Regional Government (Junta de Andalucía), owner and manager of the land and local-scale regulator of environmental legislation, and the European Commission regulator of environmental issues at European scale. The European Directive 2008/1/EC regulates integrated pollution prevention and control; at Spanish level the Law 16/2002 regulates industrial and mining activities to reduce pollution and protect soil and groundwater. In the Thematic Strategy for Soil Protection (COM 2006-231) the European Commission proposes a framework to prevent soil degradation, to preserve soil functions and to remediate degraded soil. At a Global scale the European Commission has proposed a new Environment Action Programme entitled “Living well, within the limits of our planet” that will guide environment policy up to 2020.

On April 2003, the Case Study was declared “Protected Landscape” and included in the Network of Andalusian Protected Areas (RENPA). At European level it is part of the Natura 2000 network regulated by the Habitats Directive (92/43/EEC).

fig156

Left: Population; right: GDP per capita trends for Spain and the Euro Area

Management options

As a consequence of the mine accident (in April 1998) the Regional Government of Andalusia and the Spanish Authorities launched two restoration programmes for short- and long-term management. Firstly, the soil cleaning-up was followed by the addition of organic matter and calcium rich amendments. Then, within the Guadiamar Green Corridor programme, the afforestation of ca. 4,500 ha with autochthonous species were performed (CMA, 2003). However, a few fenced plots did not undergo any remediation operations for research purposes, remaining with the sludge layer over the soil surface (Burgos et al., 2013). Additionally, relevant policies and regulations at local and European levels influenced the decontamination and remediation of the Guadiamar site.

Short-term management

At local level, the Action Plan of 1998 (just after the mine accident) regulated the investment of 165 M € to evaluate the risk and health control, to purchase the land, to remove sludge and remediate soils, to plant shrubs and trees, as well as to promote research and environmental education. The plan of Emergency Measures involved the Spanish Authorities, the Regional Government of Andalusia, and the mining company Boliden Apirsa (Arenas et al., 2003).

The removal of the tailings was carried out in two campaigns, one in 1998 and the other in 1999. As a result, 8 hm3 of sludge together with a variable layer of top soil (10–30 cm) was removed. Following that, a treatment of soil was carried out through different chemical procedures (amendments) to immobilize the heavy metals remaining in the soil. On the other hand, measures were taken to control the environmental quality in the surface waters, the subterranean waters, the estuary, the air and the living beings. In addition, a sanitary control program monitored the health of human population of the area affected by the spill.

This whole process was established in a series of laws, decrees and orders that were published from 1998 to 1999. The Regional Government approved the actions necessary for the execution of a project of regeneration and adaptation for public use called the Guadiamar Green Corridor. The properties affected by the spill were declared of urgent occupation, to the effect of compulsory purchase (Hernández et al., 2004).

The accident did not cause personal injury, but the socio-economic effects were important. More than nine townships in Seville Province were affected because they lost agricultural crops and the mining activity was stopped. Moreover, indirect effects, such as potential health risks, the impact on the local image and the devaluation of regional agricultural products on the international market, played an important role.

Long-term management

The Guadiamar Green Corridor Strategy began in 1999 and the main objectives were (Hernández et al., 2004):

  • Decontamination of the soil, water and organisms of the fluvial riverbed and of the flooded plains and the marsh damaged by the tailings and acid water
  • Restoring the functionality of the aquatic and terrestrial ecosystems damaged or destroyed by the spill.
  • Promoting a model for the management of the multiple uses of the territory in order to promote considerable ecological heterogeneity, reinstating the flood of species and natural processes between the mountain range and the coast.
  • Improving the quality of life of the inhabitants of the area through strategies of development compatible with the conservation of the functions of their natural systems.
  • Contributing to the transformation of the Network of Protected Natural Areas of Andalusia, as a network of areas connected through ecological corridors, among which the fluvial ones stand out.
  • To serve as a model of integrated planning of a Mediterranean basin that can be extrapolated to other areas and regions.

Current situation

According to the existing data, the decontamination of the soil has been effectively carried out and the levels of metals are less than that established by the Regional Department for the Environment according to the legislation.

Since 2002, there has been a continuing follow up of the soil quality, cantered fundamentally in the northern branch (between the Doblas Bridgeand and the Aznalcóllar mine). This area was the most affected due to its proximity to the spill source, causing high levels of residual contamination of arsenic and other trace elements. Despite cleaning up operations, eliminating important focal points of contamination, there is still residual contamination in some patches of land (see above).

Stakeholder involvement

Relevant end-users and local stakeholder groups

The Ministry for the Environment generally intervenes through the Guadalquivir River Basin Authority, the National Parks Administration and the Department of Environment that co-manage the Doñana National Park. The Ministry is responsible for the clean-up operations of the public hydraulic domain and the “Doñana 2005” marshland restoration project. The GeoMining Institute (IGME) is a scientific-technical body specialized in geological, geochemical and mining issues and belonging to the Central Administration. In relation to the Aznalcóllar mine, it issued reports regarding the dam stability before the accident and it advised the public Administration about the use of Aznalcóllar depleted pit as waste disposal. The Guadalquivir River Basin Authority, is a public body belonging to the Ministry of the Environment, and is in charge of the management of water resources in the Guadalquivir river basin. Its territorial responsibility is on the public hydraulic domain and it regulates surface water and groundwater protection, being one of the main regulators of the mining activity. It is responsible for monitoring the water quality of all the rivers within the Guadalquivir basin, including the authorization of the spill of the mining activity. In relation with the Aznalcóllar accident, the Regional Government of Andalusia acts mainly through three different Departments. The Department of Employment and Technology (formerly Industry and Employment) is the supervising authority for all mining activities and the main permits. The Department of Environment has jurisdiction on the Doñana Natural Park and the Environmental Impact Studies concerning the mining activity. It also launched the Guadiamar “Green Corridor” restoration project to ensure environmental rehabilitation. Finally, the Department of Agriculture has actively participated in the clean-up of agricultural land. The Guadiamar Visitor Center conveys educational programs for local schools to learn about the contamination-related environmental problems and the main remediation measures. Currently the Green Corridor is a restored area attracting visitors from nearby cities and villages to enjoy the new landscape, and practice outdoors sports. Sports associations and conservationist NGOs are end-users of the results and information provided by this remediation case study. Finally, companies developing new materials that could contribute to stabilize trace-elements and to improve soil conditions will be interested in testing and demonstrating remediating measures in this Case Study.

Involvement in the Case Study

Researchers of environmental and soil sciences in Universities of South Spain (USE, UPO, UHU and UCO among others) have been collaborating in the remediation and research programs. The Spanish Research Council (CSIC) is a research body belonging to the Central Administration and covering a wide range of scientific fields. CSIC coordinated the scientific advisory group created ad-hoc for the follow-up of the mine disaster, producing several reports about the spill and its consequences on the environment. The Doñana Biological Station (EBD), part of the CSIC, co-ordinates the research in Doñana National Park. During the last 16 years, scientists of the IRNAS, CSIC have been closely working with Government managers, investigating remediation strategies and monitoring contamination in soil and plants of the study area (e. g., Cabrera et al. 1999, 2008; Domínguez et al. 2008, 2009, 2010; Madejón et al. 2002, 2004, 2006a,b, 2007, 2009a, 2010). Main constraints and challenges to overcome include among others: the need for harmonization of soil contamination threshold levels and indicators, the need for new experiments on remediation measures and evaluation of their stability and longevity, the need for modelling soil vulnerability under different scenarios, development of new materials for remediation, to develop adaptive management programs, and to transfer technologies for diagnosis, monitoring and restoring contaminated soils. Stakeholders are actively involved in the project following the RECARE framework for stakeholder involvement, in the Case Studies, at local to the (sub-) national level. Based on a detailed stakeholder analysis, the main activities include promotion of stakeholder learning processes, stakeholder valuation of ecosystem services using local and scientific knowledge and support to other work packages.

References

Alegre JM. 2014. Study of the residual contamination by trace elements in the Guadiamar River Basin after the Aznalcóllar mine spill (in Spanish). Final Report for the Graduate Degree in Agriculture Engineer, University of Seville.

Arenas, J.M., Montes,C., Borja., F.2003. The Guadiamar Green Corridor. From an ecological disaster to a newly designated natural protected area.Consejería de Medio Ambiente, Junta de Andalucía, Sevilla, Spain.

Burgos, P., Madejón, P., Madejón, E., Girón, I., Cabrera, F., Murillo, J.M. 2013. Natural remediation of an unremediated soil twelve years after a mine accident: Trace element mobility and plant composition. Journal of Environmental Management 114, 36-45.

Cabrera, F., Ariza, J., Madejón, P., Madejón, E., Murillo, J.M. 2008. Mercury and other trace elements in soils affected by the mine tailing spill in Aznalcóllar (SW Spain).Science of the Total Environment 390, 311-322.

Cabrera, F., Clemente, L., Díaz Barrientos, E., López, R., Murillo, J.M. 1999. Heavy metal pollution of soils affected by the Guadiamar toxic flood.Science of the Total Environment 242, 117-129.

Cabrera, F., Soldevilla, M., Cordón, R., Arambarri, P. 1987. Heavy metal pollution in the Guadiamar river and the Guadalquivir estuary (south west Spain).Chemosphere 16, 463-468.

Ciadamidaro, L., Madejón, E., Robinson, B., Madejón, P. 2014. Soil plant interactions of Populus alba in contrasting environments. Journal of Environmental Management 132, 329-337.

Clemente,L.,Cabrera, F., Garcia, L.V.,Cara, J. 2000. Reconocimiento de suelos y estudio de su contaminación por metales pesados en el valle del Guadiamar. Edafología 7, 337-349.

CMA(Consejería de Medio Ambiente). 1999. Marco geográfico de la Cuenca del Guadiamar. Junta de Andalucía. Sevilla.

CMA (Consejería de Medio Ambiente). 2003.Ciencia y Restauración del Río Guadiamar. PICOVER 1998–2002. Junta de Andalucía, Sevilla.

Domínguez, M.T., Madrid F., Marañón, T., Murillo J.M. 2009. Cadmium availability in soil and retention in oak roots: Potential for phytostabilization. Chemosphere 76, 480-486.

Domínguez, M.T., Madejón, P., Marañón, T., Murillo, J.M. 2010. Afforestation of a trace-element polluted area in SW Spain: woody plant performance and trace element accumulation. European Journal of Forest Research 129, 47-59.

Gallart, F., Benito, G., Martín-Vide, J.P., Benito, A., Prió, J.M., Regüés, D.1999.Fluvial geomorphology and hydrology in the dispersal and fate of pyrite mud particles released by the Aznalcóllar mine tailings spill. The Science of the Total Environment, 242,13–26.

Grimalt, J.O., Macpherson, E. (eds.). 1999.The environmental impact of the mine tailing accident in Aznalcollar (South-West Spain).The Science of Total Environment (special issue with 22 papers), 242, 1-332.

Hernández, E., Carmona, J., Schmidt, G. 2004. Report on the situation of the Aznalcóllar Mine and the Guadiamar Green Corridor. WWF/Adena. [http://assets.wwf.es/downloads/report_on_the_aznalcollar_mine_2004_def.pdf Last view 15.10.2014]

JA 2014. Plan de Gestión de la Zona Especial de Conservación Corredor Ecológico del Río Guadiamar (ES6 180005). Consejería de Medio Ambiente y Ordenación del Territorio, Junta de Andalucía, Sevilla, 124pp.

Kemper, T. 2003. Reflectance spectroscopy for mapping and monitoring of metal mining related contamination.A case study of the Aznalcóllar mining accident, Spain.PhD Thesis.JRC.H-Institute for environment and sustainability (Ispra).

López-Pamo, E., Barettino, D., Antón-Pacheco, C., Ortiz, G., Arránz, J.C., Gumiel, J.C., Martínez-Pledel, B., Aparicio, M., Montouto, O. 1999. The extent of the Aznalcóllar pyritic sudge spill and its effects on soils.The Science of Total Environment 242, 57-88.

Madejón, P., Murillo, J.M., Marañón, T., Cabrera, F., López, R. 2002.Bioaccumulation of As, Cd, Cu, Fe and Pb in wild grasses affected by the Aznalcóllar mine spill (SW Spain).The Science of the Total Environment 290, 105-120.

Madejón, P., Marañón T., Murillo J.M., Robinson B. 2004. White poplar (Populus alba) as a biomonitor of trace elements in contaminated riparian forests. Environmental Pollution 132, 145-155.

Madejón, P., Murillo, J.M., Marañón, T., Espinar, J.L., Cabrera, F. 2006a. Accumulation of As, Cd and selected trace elements in tubers of Scirpus maritimus L. from Doñana marshes (South Spain).Chemosphere 64, 742-748.

Madejón, P., Marañón T., Murillo J.M., 2006b. Biomonitoring of trace elements in the leaves and fruits of wild olive and holm oak trees.Science of the Total Environment 355, 187-203.

Madejón, P., Murillo, J.M., Marañón, T., Lepp N. 2007. Factors affecting accumulation of thallium and other trace elements in two wild Brassicaceae spontaneously growing on soils contaminated by tailings dam waste.Chemosphere 67, 20-28.

Madejón, E., Madejón, P., Pérez de Mora, A., Burgos, P., Cabrera, F. 2009a. Trace elements, pH and organic matter evolution in contaminated soils under assisted natural remediation: a four-year field study. Journal of Hazardous Materials, 162, 931–938.

Madejón, P., Domínguez, M.T., Murillo, J.M., 2009b. Evaluation of pastures for horses grazing on soils polluted by trace elements.Ecotoxicology 18, 417–428

Madejón, P., Perez-de-Mora, A., Burgos, P., Cabrera, F., Lepp, N.W., Madejón, E. 2010. Do amended, polluted soils require re-treatment for sustainable risk reduction? – Evidence fromfield experiments. Geoderma, 159, 174-181.

Madejón, P., Domínguez, M.T., Murillo, J.M. 2012. Pasture composition in a trace element-contaminated area: the particular case of Fe and Cd for grazing horses. EnvironmentalMonitoring andAssessment 184, 2031–2043.

Madejón, P., Ciadamidaro, L., Marañón, T., Murillo, J.M. 2013.Long-term biomonitoring of soil contamination using poplar trees: accumulation of trace elements in leaves and fruits. International Journal of Phytoremediation 15, 602–614.

Nagel,I.,Lang, F., Kaupenjohann, M., Pfeffer, K-H.,Cabrera, F., Clemente, L.. 2003. Guadiamar toxic flood: factors that govern heavy metal distribution in soils. Water, Air & Soil Pollution 143, 211-224.

Panagos, P., Liedekerke, M.V., Yigini, Y., Montanarella, L. 2013. Contaminated sites in Europe: review of the current situation based on data collected through a European network.Journal of Environmental and Public Health. Article ID 158764.

Salvany, J. 2004. Tilting neotectonics of the Guadiamar drainage basin, SW Spain. Earth Surface Processes and Landforms, 29, 145–160.

Bartolomé, J., Vega, I. 2002. Mining in Doñana. Leraned lessons. WWF. 28 pp.

United Kingdom Case Study – Loss of soil biodiversity

The researchers assessed the long-term effects of chemical manipulations to the soil and the resulting effect of pH change on soil biodiversity and function.  The experiment involved applying amendments of ferrous sulphate and elemental sulphur.

UK Video 

 Control    Ferrous Sulphate    Elemental Sulphur
UKexperimentControl   UKexperimentFerrousSulphate   UKexperimentElementalSulphur

         Photo credit: Marta Gil Martinez

Final Results

Earthworms

 UKResults1   UKResults3    

Nematodes

 UKResults4
Figure 1. Earthworm biomass (a) and abundance by functional group (b) and nematode abundance (c) by feeding group (d) were evaluated across treatments (n=10) in Nov 2016. Acid grassland and heathland were included as reference plots (n=4).

For more information about this RECARE experiment, please contact Mark Tibbett This email address is being protected from spambots. You need JavaScript enabled to view it.

Geographical description

The Isle of Purbeck is not a true island but a peninsula of ~200 km2 on the south coast of England. It lies to the West of The New Forest National Park and is in the County of Dorset. It has a mild temperate Atlantic climate with mean annual rainfall of around 777 mm.y-1 and an average temperature of around 11oC. Purbeck is a complex multifunctional, multi-land-use landscape with a range of competing pressures from arable farming, high and low-intensity livestock grazing, touristic land use with quarrying and military areas all expecting their share of the lands' ecosystem services. The soils are highly contrasting in pH, both naturally and through anthropogenic manipulation and are generally sandy to sandy loams, derived from a complex underlying geology.

fig171

 Location and Digital Elevation Model (DEM) of the Isle of Purbeck (Source: SRTM).

Main soil threat

The Isle of Purbeck is a multifunctional landscape with enormous pressure placed on soil resources due to the contrasting and competing land uses, past and present. The major soil threat here is a loss of soil biological function, linked to depleted biodiversity due to persistent physical and chemical manipulation of the land. Degradation has been caused by various means, most insidious is the large-scale manipulation of soil pH for competing agriculture uses which has led to heavy lime (and historic marl) application for arable land use, and subsequent intense sulphur application to reverse such previous alkalinisation. The latter was done to provide low-intensity grazing land, in keeping with the traditional and historic land uses of the area. This has led to a landscape with soil pH ranging from 3 to 8.5 often through artificial manipulation. The treatment of the soil in such a way has led to a clear loss in microbiological function where we have seen microbial biomass decline by one-half and biodiversity has been reduced by over two-thirds and where plant-microbe symbionts are absent or of the wrong type. The landscape has also been subject to other degrading activities including extensive recreational use in some areas, military disturbance (including the use of high powered ordnance) and quarrying. These have all contributed to a loss of biodiversity in the soil to varying degrees.

Other soil threats
The acidification has caused significant loss of microbial diversity and plant life leading to areas subject to soil erosion which can occasionally leads to complete top soil loss. The acidification has also led to the mobilisation of toxic metal cations in soils and run-off which provides additional threats to the effected sites and the surrounding environment (Green et al., 2007). Quarrying and military land uses alone have led to degraded soils that are poorly productive and fertile for reasons beyond biodiversity loss. Unrelated directly to biodiversity effects, but likely affecting biodiversity, the Case Study also includes areas that display significant soil erosion, as well as land degraded and threatened by coastal erosion and cliff failures.

IsleofPurbeck1Land areas of contrasting acidification

IsleofPurbeck3

The challenge is to rejuvenate the critical biodiversity in the soil after disturbance and this requires a detailed assessment of the functions that have been lost (nutrient cycling, symbionts, decomposition, pathogen control and so on). The relationship between diversity and function is not well established in soils generally; partly, at least, due to the large component of functional redundancy, and this will need to be assessed for our soils. The reintroduction of lacking diversity may require interventions such as inoculation, modified tillage, modified nutrient management and phytoremediation, depending on the initial results of the study.

Natural Environment

Geology & Soils

Geology of the Isle of Purbeck is shown in the table below. Table below shows the area coverage of geological deposits, indicating that Tertiary sand, Jurassic limestone and clay, and drift over Mesozoic and Tertiary clay and loam constitute almost 60% of the study area. There is also an abundance of chalk deposits, which contribute to intensive quarrying activity in the area.

fig172 Geology of the study area. Source: NSRI (2001)

 

GeologyArea [ha]% Area

Cumulative

Area %

Tertiary sand 5,425.04 26.01  
Jurassic limestone and clay 3,378.31 16.19 42.20
Drift over Mesozoic and Tertiary clay and loam 3,341.61 16.02 58.22
Mesozoic and Tertiary sand and loam 1,744.16 8.36 66.58
Chalk 1,239.96 5.94 72.53
Sandy drift 1,214.27 5.82 78.35
Jurassic and Cretaceous clay 660.97 3.17 81.52
River alluvium over peat 626.27 3.00 84.52
Other 3,229.63 15.48 100.00
TOTAL 20,860.22 100.00 100.00

Distribution of main geological deposits within the Isle of Purbeck

The soils in the Isle of Purbeck are highly contrasting in pH, both naturally and through anthropogenic manipulation and are generally sandy to sandy loams, derived from a complex underlying geology. They are dominated by sandy and clayey soils oftentimes situated over chalk and limestone deposits. The following figure and table provide detailed information on the soils of the area. These soils are characterized by high organic carbon contents, with soils containing up to 2% of organic carbon constituting a relatively small portion of the area (see below).

fig173

Soil associations of the case study area at mapping scale of 1:250 000. Explanations of soil association symbols are given below. Source: NSRI (2001)

 

Soil AssociationDominant soil description Area [ha]% Area

Cumulative

Area %

641b deep sandy 5,425.04 26.01  
343d shallow clay over limestone 3,378.31 16.19 42.20
711g seasonally wet loam to clayey over shale 3,341.61 16.02 58.22
571g loam over sandstone 1,744.16 8.36 66.58
341 shallow silty over chalk 1,221.65 5.86 72.44
861a seasonally wet deep sand 1,214.27 5.82 78.26
712b seasonally wet deep clay 660.97 3.17 81.43
813a seasonally wet deep clay over peat 626.27 3.00 84.43
Other   3,247.94 15.58 100.00
TOTALS 20,860.22 100.00 100.00 100.00

Main soil associations of Isle of Purbeck listed in descending area coverage order. The table provides further explanation to soil association symbols(above)

fig174

Average organic carbon contents in the top 30 cm layer of soil. Source: NSRI (2001).

Land Use

Land use of the Isle of Purbeck is dominated by pastures, followed by agricultural land and heathland (below).

 fig175

Major land use classes within the Isle of Purbeck case study area derived from the CORINE 2006 land use/land cover map (EEA, 2014). The black lines indicate the location of parishes. The protected areas comprise several datasets (see text for details) and were compiled from data obtained from the British Environment Agency (EA, 2014)

 

A fair part of the area is covered with either coniferous or deciduous woodland. Approximately a quarter of the area is under some form of protection, and a large part of Lulworth parishes is owned by the Ministry of Defence. Settlements are mostly discontinuous, with the largest concentration around the town of Swanage. The landscape has also been subjected to other degrading activities including extensive recreational use in some areas, military disturbance (including the use of high powered ordnance) and quarrying.

 

fig176

Image of Landscape Matrix in the Isle of Purbeck

Climate

The Case Study has a mild temperate Atlantic climate with mean annual rainfall of around 777 mm y-1 and an average temperature of around 11 oC.

 

fig177

Left: Average annual; right: mean monthly precipitation and temperature at the Isle of Purbeck.

Drivers and pressures

The drivers to soil biodiversity decline are many and include many soil threat considered in RECARE. Many of the drivers related to the either the overuse of land (by people or animals) or changes in land management due to policies enacted at EU, National and regional levels. The major threats include: soil compaction on arable, woodland and pasture land, footpath erosion and compaction, soil sealing, coastal erosion, acidification of chalk hills by gorse, quarrying and salt blast (windblown salt from the sea). All of these impact on soil biodiversity.

Status of soil threat

Preliminary data indicate a significant decline in parts of the microbial community. Preliminary analysis suggests significant shits in microbial function as a result of acidification.

ThreatExisting solutionPotential solution
Soil compaction on arable land Cultivation technique, proper timings, subsoiling, tillage technique Drainage
Soil compaction on pasture land    
Soil compaction in woodland Using horses instead of heavy machinery during forestry work to reduce damage to the forest floor  
Footpath erosion and compaction   Changing access policy, re-routing, building stone steps
Soil sealing   Preventing further residential developments, houses built at lower densities, gardens rather than concrete, proportional approach to development
Intensive agriculture Incentivising less intensive agriculture, a farmers cooperative promoting local products Precision agriculture, common agricultural policy, people prepare to pay more for food
Coastal erosion Soil nails, netting, drainage to prevent slippage  
Acidification of chalk hills by gorse Clearing of the gorse, grazing, burning  
Quarrying Restoration programmes dictated by planning policy  
Preventing soil development by restoring heathland   Ceasing the restoration
Wind erosion on arable land   Plant trees around field, increase vegetation cover with grass
Salt blast    
Cultural ignorance   Education, the Common Agricultural Policy
Proximity of large urban area    

List of soil threats identified including existing management options and potential future solutions

WOCAT Maps

Maps on the current state of land use, soil degradation and soil conservation in the case study area have been produced using the WOCAT (World Overview of Conservation Approaches and Technologies) methodology

The steps of this process are as follows:

1) The area to be mapped is divided into distinctive land use systems (LUS).
2) The team gathers the necessary data on soil degradation and conservation for each LUS using a standardised questionnaire, in close consultation with local land users, and supported where possible by remote sensing or field data.
3) For each LUS, the soil degradation type, extent, degree, impact on ecosystem services, direct and indirect causes of degradation, as well as all soil conservation practices, are determined.
4) Once collected, the data is entered in the on-line WOCAT-QM Mapping Database from which various maps can be generated.

Following the principles of all WOCAT questionnaires, the collected data are largely qualitative, based on expert opinion and consultation of land users. This allows a rapid and broad spatial assessment of soil degradation and conservation/SLM, including information on the causes and impacts of degradation and soil conservation on ecosystem services.

More details about the methodology used to produce these maps and their interpretation can be found here.

Land Use (click on maps to expand)

United Kingdom Isle of Purbeck land use typesS United Kingdom Isle of Purbeck area trend land use systems United Kingdom Isle of Purbeck trend in land use intensity

 Degradation

The degree of degradation reflects the intensity of the degradation process, whilst the rate of degradation indicates the trend of degradation over a recent period of time (approximately 10 years).

United Kingdom Isle of Purbeck dominant types of soil degradationS United Kingdom Isle of Purbeck degree of degradationS United Kingdom Isle of Purbeck rate of degradationS

Conservation measures

The "effectiveness" of conservation is defined in terms of how much it reduces the degree of degradation, or how well it is preventing degradation. The Effectiveness trend indicates whether over time a technology has increased in effectiveness.

United Kingdom Isle of Purbeck dominant conservation measuresS United Kingdom Isle of Purbeck effectiveness of conservation measuresS United Kingdom Isle of Purbeck conservation effectiveness trendS

Administrative and socio-economic setting

Protected areas depicted in figure above are under a combination of several forms of protection. These are RAMSAR sites, Special Sites of Scientific Interest (SSSI), Special Areas of Conservation (SAC), and Special Protection Areas (SPA). RAMSAR sites are dedicated to protection of wetlands and waterfowl habitats. SSSIs aim at protection of sites hosting wildlife and notable natural features. SACs are areas that offer protection to wildlife and habitats as an initiative of an EU directive, and SPAs are dedicated to conservation of wild birds.

fig178

 Population in the Purbeck District (left) and GDP per capita trends (right)

Management options

The challenge here is to rejuvenate the critical biodiversity in the soil after disturbance and this requires a detailed assessment of the functions that have been lost (nutrient cycling, symbionts, decomposition, pathogen control and so on). Generally, the relationship between diversity and function is not well established in soils, partly, due to the large component of functional redundancy. This relationship will need to be assessed for the soils of the Case Study. The reintroduction of lacking diversity may require interventions such as inoculation, modified tillage, modified nutrient management and phytoremediation depending on the initial results of the study.

Stakeholder involvement

Relevant end-users and local stakeholder groups include;

• Farmers, landowner and land managers
• Natural England
• Ministry of Defence
• Dorset County Council
• National Trust

Learning platforms for Stakeholders were be established in order to facilitate knowledge exchange and mutual learning between the different participants from local to national level. Open field days were held alongside a short course in remedial measures. 

References

EA, 2014. http://www.geostore.com/environment-agency/WebStore?xml=environment-agency/xml/ogcDataDownload.xml

EEA, 2014. http://www.eea.europa.eu/data-and-maps/data/clc-2006-vector-data-version-3

NSRI, 2001. The National Soil Map of England and Wales 1:250,000 scale. National Soil Resources Institute, Cranfield University, UK. http://www.landis.org.uk/data/natmap.cfm

Case Study Experiment - immobilization of heavy metals using soil amendments

The researchers tested the effectiveness of different soil amendements to reduce the heavy metals mobility in soil and the uptake by plants.

 DSCF1048 1
 Factory site, Copsca Mica

 Final Results

The main results from the experimental field were:

  • The highest increase in pH values was for soil treated with Na-bentonite (7.16) compared with the control (5.18).
  • In both experimental years, concentrations of available cadmium, lead and zinc decreased significantly with the application of amendments, and they followed the order (highest to lowest): control > natural zeolite > manure > Na-bentonite > dolomite.
                   Results
  • Compared with the control all treatments had statistically significant effects on metals accumulation in biomass but the highest decrease of metal content in the plant was after dolomite application.

Further details about this experiment can be found in the fact sheet HERE (RO) and in the project report HERE.

For more information about this RECARE experiment, please contact  Mihail Dumitru This email address is being protected from spambots. You need JavaScript enabled to view it.

Geographical description

The Case Study area is located in Sibiu county, around the most important factory for processing of non-ferrous ores – Copsa Mica. Copsa Mica is located in the Valley of Târnava Mare River, in north of Sibiu, 33 km east of Blaj and 12 km southwest of Medias. Copsa Mica region has temperate continental clime with an average annual temperature of 8.6°C. Long-term annual precipitation ranges from 900 to 1300mm. The population in 2010 was 5573, down 13% from the population in 1989. The main soil types in the area are Haplic Regosols and/or Regosols; Albic Luvisols; Haplic Phaeozems; and Fluvisols, whilst the main crops are maize, wheat, oat, potatoes and alfalfa. Also, livestock, dairy cow, sheep and horses are also evident. The main pollution is caused by S.C. Sometra S.A., a metallurgical plant.

fig161

 Location and general view of the Copsa Mica

Main soil threat

Copşa Mică is a city developed around two industrial areas, both with high pollutant potential. The main pollutants identified in this area were cadmium, copper, lead and zinc. Moreover, this city was presented in Blacksmith Institute and Green Cross Switzerland Report 2012 - "World's Worst Polluted Places" as examples of high cadmium pollution (www.worstpolluted.org).

Other soil threats

Soil erosion is a problem as the polluted area is characterized by a very complex geomorphological pattern, with slopes of various different gradients, ridges and plateaus. Pollutant emissions from non-ferous metallurgical factory are also responsible for the decrease of soil structural stability and soil pH. Due to the lithological susceptibility of land to erosion, the naturally developed sheet and rill or gully erosion processes have intensified.

CopsaMicaPollution Source

 

 

 

 

 

 

 

Obsolete technologies and the lack of adequate filtering for the chimney stacks resulted in: a.) significant accumulation of heavy metals in arable land, the values being excessive to the maximum plough layer; b.) increase of heavy metal content in vegetation and crops; c.) decrease of soil structural stability; d.) increase of soil acidity due to pollution with sulphur oxides; and e.) disturbance of microbiological activity with negative consequences on organic matter quality and nutrient supply. The polluted areas where the pollutant content in soil (0-20cm) exceeds the alert thresholds for sensitive use of land, according to Vrînceanu et al. (2010), are: 7040 ha – for zinc (content in soil exceeding 300 mg/kg); 10320 ha – for cadmium (content in soil exceeding 3 mg/kg); 22565 ha – for lead (content in soil exceeding 50 mg/kg).

In Romania, most work concerning remediation of heavy metals polluted soil has focused on immobilization of these pollutants using different types of inorganic additives, such as zeolitic tuff, bentonite, volcanic tuff, and biosolids. Although the situation is well documented, and there have been some attempts to remediate these soils, until now, no feasible solution for the decontamination of this large region has been found. In Romania, these technologies for remediation of polluted soils are not yet commercially available, possibly due to the inadequate awareness of their advantages and principles of operation. The effectiveness of the amendments could be assessed in several different ways including chemical methods (e.g. selective and sequential chemical extractions, adsorption/desorption isotherms, long-term leaching) and biological (e.g. plant growth and dry-matter yield, plant metabolism, etc.).

Special focus will be given to identification of the most efficient low-cost soil amendments that could be used for remediation of polluted soil from the Copsa Mica area. An understanding of the forms of contaminants present in the soil can be used to make reliable predictions about sustainability of the in situ immobilization. Further, the results of our studies could be used to quantify the underlying economics, as a support for public acceptance and to convince policymakers and stakeholders.

Natural environment

Geology & Soils

Soils from Copşa Mică have been formed in varied conditions of relief with morphologic characteristics, which succeed on vertical, from mountains, hills, and depressions. The main soil types in the area are Haplic Regosols and/or Regosols; Albic Luvisols; Haplic Phaeozems; Eutricambosols and Fluvisols. In the bottom land area of Târnava Mare River are developing Fluvisol, and in the terrace and hill areas prevail Eutricambosol and Phaeozem types. The Fluvisol type develops on the fluvial parental material, being manifesting as sands and gravel in alternation with centimetre levels of clay. The underground water level can be found at 2 m of soil profile and can influence its formation. Within the soil profile, the water drainage is very good. The Phaeozem type has a considerable development, especially in the inferior part of the hill and terrace areas, at north and south of Copşa Mică area. The relief is weakly inclined, 20-30°. The parental material is manifesting as marls, clays and Pannonian siltstone (Damian et al., 2008). 

fig162

Soil groups according to the FAO classification (left) and land use in the Case Study (right) Source: JRC

Land Use

According to data from the Land Parcel Identification System (LPIS) provided by Sibiu County Center of the Agency for Payments and Intervention in Agriculture (2012), arable crops, located mainly in the lowlands, cover 60.4% of the total area (2,818.6 ha), and grassland covers 34.9% (1,627.3 ha). Orchards and vineyards represent a very small proportion of the total cultivated area, only 2.3% (106 ha) and 2.4% (110.3 ha) respectively. Deforestation has led to the formation of pastures predominantly characterised by species of Festuca rubra, Poa pratensis, Agrostis tenuis, and having a moderate grazing value. In spontaneous vegetation, species like Xanthium strumarium, Calamagrostis pseudophragmites, Asclepias syriaca, Vernbascum phlomoides, Phragmites australis, etc. were identified. Crops are cultivated both on well-drained floodplains as well as on terraces. The main cultivated species in the area are: wheat (Triticum aestivum ssp. Vulgare), oats (Avena sativa), maize (Zea mays) potatoes (Solanum tuberosum), sugar beet (Beta vulgaris var. Saccharifera), beans (Phaseolus vulgaris), peas (Pisum sativum) and vegetables: carrot (Daucus carota), parsley (Petroselinum hortense), and celery (Apium graveolens), all at a low yield due to pollution.

fig163

General view of agricultural land from Copşa Mică (Photo: D.M. Motelica).

Climate

The climate in the Case Study is temperate and continental, with four distinct seasons. Available records indicated that the annual average temperature is 9.1 °C. The coldest month is January when average monthly temperature is -3.3 °C. Regarding rainfall is noticed that there is a distribution by type of summer rainfall (about 60% of the annual precipitation occurs during the summer), with the maximum record in June (93 mm). According to information from ATEAM database, the mean annual precipitation ranges between 397 mm and 838 mm (see below). Air circulation is mainly oriented in the NE – SW direction. Characteristic of the Case Study are periods of calm atmosphere (64%), which causes stagnation of air masses and deposition of pollutants in the basin of Târnava Mare River. Also, air masses are channelled along Târnava Mare River and Vista River.

 fig164

Annual precipitation / average temperature (left) and average monthly precipitation/temperature (right) at Copşa Mică area (1961-2000 period of record)

Hydrogeology

Hydrologically, the area belongs to the Mures River basin with the main tributary Târnava Mare River. The territory is traversed by the Târnava Mare, from East to West, the largest collector of surface waters. The most important tributary is the Visa River. A number of temporary streams are also met in the area.

Drivers and Pressures

In Romania, chemical pollution of soils is affecting approximately 0.9 Mha of soil, of which 0.2 Mha are affected by excessive pollution. Adverse effects are particularly strong related to pollution by heavy metals (Cu, Zn, Pb and Cd) and sulphur dioxide, identified especially in Baia Mare, Zlatna and Copșa Mică (Elekes, 2014). The major source of pollution in the Case Study has been the non-ferrous metallurgical plant of Copșa Mică, which was built in 1939 and initially produced zinc. After the World War II, the plant diversified products and increased its production capacity. In 2005 the metallurgical plant was specializing in both zinc and lead extraction from concentrated ores and in the recovery of the associated metals, such as cadmium, antimony, copper, gold and silver. Due to the numerous periods during which exceedance of the maximum admissible air pollution limits was reported, the company proceeded to replace facilities with a technologically modern sulphuric acid plant with a limited pollution impact on soil. In fact, since February 1st, 2010, plant production has temporarily stopped.

Contamination of soil in this area evolved mainly in two ways: 1) through the emissions of powders charged with suspended particles of heavy metals from point source pollution; 2) through wastes from the industrial spoil bank of the metallurgical factory. Point source emissions were transported by air masses and deposited on the land, leading to an increase of metal content in the top soil layer with dramatic effects on vegetation. Various researchers report that, from 1999 to 2008, the maximum annual deposits decreased in intensity, and their content in heavy metals (g/m2) also decreased from 315.02 to 5.90 for zinc, from 191.56 to 3.69 for lead, and from 2.79 to 0.008 for cadmium (Lăcătușu and Lăcătușu, 2010). The spoil bank is situated W-NW of the town, on the left bank of the Târnava Mare river, upstream of the junction of the Visa River. The spoil bank has an estimated area of 192,308 m2 and a storage volume of 2,000,000 m3. In 2006, it contained 3,150,000 t of wastes consisting of pyrite ashes, clinker, building materials and furnace slag. The nature of these materials allows an easy percolation of meteoric waters (Comănescu et al., 2010). The heavy metal contamination in the study area led to a significant decrease of biomass production, acidification of soil, decrease of organic matter content in the soil as well as to the physical degradation of soil.

The reduction of the activities of the industrial platform triggered a large scale migration towards the rural areas surrounding Copșa Mică. Small landowners in the neighbouring villages still use the land for subsistence agriculture, even though it is polluted, due to lack of awareness and poverty. The agricultural use of the land presents a risk for population health and also reduces the available options for soil remediation. Finally, due to both low soil fertility (as a result of contamination) and lack of financial resources, there is land abandonment.

Status of soil threat

Soil degradation in the study area is a result of the combination of natural factors (high declivities, friable rocks) with anthropogenic ones (deforestations, overgrazing, heavy metal and black carbon soot pollution). The process is amplified by the contribution of airborne and waterborne pollutants, which also end up in soil (Comănescu et al., 2010). The main soil threat is posed by heavy metal contamination. The mismanagement of the non-ferrous metallurgical activities of the Copşa Mică industrial platform without taking in account the environmental damage, lead to a historical accumulation of heavy metals (Cd, Zn and Pb) in the soil. Heavy metal content in the soil varies significantly depending on soil type, topography and predominant wind direction. According with results obtained in previous research projects (Vrinceanu et al. 2010), in 2005 polluted areas where the pollutant content in soil (0-20 cm) exceeds the alert thresholds for sensitive use of land are: 7,040 ha – for zinc (content in soil exceeding 300 mg/kg); 10,320 ha – for cadmium (content in soil exceeding 3 mg/kg); 22,565 ha – for lead (content in soil exceeding 50 mg/kg). Data from previous research studies indicate that the polluted land area, assessed during 1991-1993, to 21,875 ha, was very close to that reported for 2005, equal to 22,565 ha. The difference of only 690 ha, showed a slight increase in the polluted area in the time since the year 1991 to 2005, which demonstrates a systematic reduction in the pollution intensity over time (Lăcătușu and Lăcătușu, 2010).

fig165

Spatial distribution of cadmium and lead in soil around Copşa Mică

WOCAT maps

Maps on the current state of land use, soil degradation and soil conservation in the case study area have been produced using the WOCAT (World Overview of Conservation Approaches and Technologies) methodology

The steps of this process are as follows:

1) The area to be mapped is divided into distinctive land use systems (LUS).
2) The team gathers the necessary data on soil degradation and conservation for each LUS using a standardised questionnaire, in close consultation with local land users, and supported where possible by remote sensing or field data.
3) For each LUS, the soil degradation type, extent, degree, impact on ecosystem services, direct and indirect causes of degradation, as well as all soil conservation practices, are determined.
4) Once collected, the data is entered in the on-line WOCAT-QM Mapping Database from which various maps can be generated.

Following the principles of all WOCAT questionnaires, the collected data are largely qualitative, based on expert opinion and consultation of land users. This allows a rapid and broad spatial assessment of soil degradation and conservation/SLM, including information on the causes and impacts of degradation and soil conservation on ecosystem services.

More details about the methodology used to produce these maps and their interpretation can be found here.

 Land Use (click on maps to expand)

Romania Copsa Mica land use typesS Romania Copsa Mica area trend land use system Romania Copsa Mica trend in land use intensityS

 Soil Degradation 

The degree of degradation reflects the intensity of the degradation process, whilst the rate of degradation indicates the trend of degradation over a recent period of time (approximately 10 years).

Romania Copsa Mica dominant types of soil degradationS Romania Copsa Mica degree of degradationS Romania Copsa Mica rate of degradationS

 Soil Conservation Measures

The "effectiveness" of conservation is defined in terms of how much it reduces the degree of degradation, or how well it is preventing degradation. The Effectiveness trend indicates whether over time a technology has increased in effectiveness.

Romania Copsa Mica dominant conservation measuresS Romania Copsa Mica effectiveness of conservation measuresS Romania Copsa Mica conservation effectiveness trend

 Effects on soil threat on ecosystem functions

The following table lists the effects of soil contamination on the soil functions at the Copşa Mică area.

Functions of soilExplanationEffect
Biomass production Loss of agricultural and food production potential H
Environmental interactions The high mobility and bioavailability of these pollutants lead to contamination of groundwater and crops, having severe effects on human health. H
Gene reservoir/ Biodiversity pool Due to eco-toxicological effects of contamination, some species were affected. M
Physical medium Base for built development is affected (mainly due to landslides). L
Source of raw materials Raw material collection is not affected. N
Carbon pool Data on C stocks is not available U
Cultural heritage A number of heritage buildings have been affected by acid rain L

Effects of soil contamination on soil functions (N: None; L: Low; M: Medium; H: High; U: Unknown)

Administrative and socio-economic setting

Overview

In Romania, the Ministry of Environment and Climate Change (MMSC) is the main authority in charge of national environmental policy, water management and forestry management, fulfilling the role of state authority in charge of synthesis, coordination and control in these areas, directly or through specialized technical bodies and authorities or public institutions. According to the legislation, the MMSC is designated as the Managing Authority for the Sectoral Operational Programme for Environmental Infrastructure. The National Environmental Protection Agency (NEPA) under the MMSC, specializes in central public administration and is committed to implement policies and legislation on environmental protection through decentralized agencies that ensure all economic and social factors to comply with the Law of Environmental Protection, the National Action Program for Environmental and National Strategy for Sustainable Development. Soil contamination assessments are carried out according to Order 756/3.11.1997, which regulates the normal values, alert thresholds and action levels for different trace elements by land use type.

fig166

Population in Copşa Mică(Source: Sibiu County Department of Statistics)
and annual growth rate of Gross Domestic Product (GDP) volume for Romania and the Euro Area (Source: Eurostat).

Management options

As of 2011, the activities of the metallurgical factory have stopped and thus the input of contaminants in the soil has significantly decreased; nevertheless, the historical pollution continues to affect soils in the area.

Short term management

In order to control the pollution effects in the Copșa Mică area, some urgent measures are required: 1) measures to reduce the effects of heavy metal contamination, decreasing the input of these contaminants in the food chain; 2) measures for decontamination of the local polluted soils.

Soil and crop management methods can help prevent uptake of pollutants by plants, leaving them in the soil. Following management practices will not remove the heavy metals but will help to immobilize them in soil and reduce their transfer into the food chain: increasing the soil pH, using inorganic additives (limestone, dolomite, etc.), applying well fermented organic fertilizers, applying additives with high affinity for heavy metal cations (for in situ immobilization), selecting plants for use on contaminated soils, growing pollution resistant species especially the species without food value. Also very important are the ecological restoration activities to control erosion and landslides and the afforestation with species resistant to pollution (acacia, willow, hornbeam, etc.). Once metals are introduced in the soil, it is hard to eliminate them from the environment. Traditional treatments (chemical treatments, physical separation, high temperature treatment, etc.) for decontamination of soil polluted with heavy metals do exist but their cost is prohibitive for such a large contaminated area. An alternative method for decontamination is phytoremediation. Research has demonstrated that plants are effective in cleaning up contaminated soils. Phytoremediation is slower than traditional methods but cheaper.

Long term management

The particularities of the Case Study (large polluted area, historical pollution, large number of landowners, agricultural use of land, etc.), require the development of a long term management plan of land use in order to reduce the effects of heavy metal pollution and to increase the quality of life in this area. After the implementation of a remediation strategy, the systematic monitoring of key indicators and processes is very important. It is also important to improve the national legal framework in order to avoid the exploitation of highly polluted land for crop production and grazing and to provide alternative land use solutions for stakeholders.

Stakeholder involvement

Relevant end-users and local stakeholder groups include;

  • Land users and farmers from polluted area.
  • The main polluter – S.C. SOMETRA S.A. a Romanian metallurgical company.
  • Local NGO's for Environmental Protection and local authorities.
  • Regional Environmental Protection Agency Sibiu (REPA Sibiu).

There will be organization of a demonstrative field in polluted area where the most efficient immobilization treatments will be presented. Meetings will take place with local authrities, REPA Sibiu, farmers and NGO's.  This will include the National Rural Development Programme, a training module concerning agricultural practices in polluted areas with measures to mitigate the pollution effects. A sociological study will aslo evaluate the social and economic status of the community from the affected area, and to assess the level of acceptance regarding the remediation measures proposed.

Gender and stakeholder workshops

At the first workshop, there were invited 7 women and 10 men, in order to achieve a good gender balance. Both men and women are land owners, providers of information to the general public, land managers, land workers and representatives of local authorities. Representatives of public institutions, whose role is to provide and monitorize fundings for landowners, were mainly men.

Regarding the choice of how to ensure sustainable management of land in order to reduce soil degradation in the region, participants had different options depending on their gender.  Therefore women had considered as the most appropriate approach is "organizing training activities to increase understanding and acceptance related to land use change in order to reduce human exposure to contaminants through the food chain (replacing annual crops with biofuel crops, afforestation etc.) On the other hand, developing alternative sources of income for private individuals (tourism, manufacturing of raw materials, etc.) could be another solution to change the agricultural use of contaminated land.  The alternative approach suggested by men, was an initiation of lobbying in order to improve the legal framework for contaminated land use (granting compensatory payments to landowners from contaminated areas, etc.).

References

Comănescu, l., Nedelea, A., Paisa, M., 2010. Soil pollution with heavy metals in the area of Copșa Mică town – Geographical considerations, Metalurgia International XV 4, 81-85.

Damian, F., Damian, Ghe., Lăcătușu, R., Iepure, Ghe., 2008. Heavy metals concentration of soils around Zlatna and Copsa Mica smelters Romania, Carpath. J. of Earth and Environmental Sciences, 3(2), 65-82.

Elekes, C.C., 2014. Assessment of historical heavy metal pollution of land in the proximity of industrial area of Targoviste, Romania, available at: http://dx.doi.org/1057772/58304.

Lăcătușu, R., Lăcătușu, A.R., 2010. Evolution of heavy metals pollution from Copșa Mică. Scientific Papers, UASVM Bucharest, Series A, LIII, 85-92 (http://agronomyjournal.usamv.ro/pdf/issue2010.pdf).

Suciu I., Cosma C., Todică M., Bolboacă S.D., Jäntschi L., 2008. Analysis of soil heavy metals pollution and pattern in Central Transylvania. International Journal of Molecular Science, 9, 434-453.

Vrinceanu, N.O., Dumitru, M., Motelica, D.M., Gamenț, E., 2010. Heavy metals behaviour in soil-plant system (in Romanian), ISBN 978-973-729-229-2, 204 pp

 

Case Study Experiment - increasing organic matter with crops and conservation agriculture

The Italian researchers tested the effectiveness of continuous soil cover and conservation agriculture practices to increase organic matter content.  They compared untreated soil compared with cover crop and conservation agriculture management systems.
Sustainable agriculture
Increasing organic matter content through long-term sustainable agriculture systems

Final Results

Experimental results showed significant differences in crop production between treatments, with lower average yields in CA (5.4 Mg ha-1) than in CC (7.9 Mg ha-1) and CV (8.5 Mg ha-1). Continuous soil cover in CA and CC determined the soil-water balance through increased evapotranspiration and reduced percolation (-30%) relative to CV. On the other hand, CC and CV tillage operations significantly affected NO3-N concentrations, with higher soil solution concentrations in tilled (CV = 74.6 mg l-1; CC = 58.1 mg l-1) than in untilled (CA = 14.0 mg l-1) systems. Model results emphasised that SLM practices responded differently in the short and long 30 terms due to initial inertia to C changes and lower N2O fluxes, followed by higher SOC sequestration, and increased N2O emissions. These results demand time–dependent studies that weigh agro-environmental benefits provided by SLM practices against management alternatives to find a suitable compromise for stakeholders.

Further details about this experiment can be found in this project report HERE.

Scientific articles

Pituello, C., Dal Ferro, N., Francioso, O., Simonetti, G., Berti, A., Piccoli, I., Pisi, A. and Morari, F., 2018. Effects of biochar on the dynamics of aggregate stability in clay and sandy loam soils. European Journal of Soil Science, 69(5), pp.827-842. https://doi.org/10.1111/ejss.12676

Chiara Pituello, Nicola Dal Ferro, Gianluca Simonetti, Antonio Berti, Francesco Morari (2015) Nano to macro pore structure changes induced by long-term residue management in three different soils. Ecosystems and Environment, Vol 217, 1 February 2016, Pages 49–58 doi:10.1016/j.agee.2015.10.029

Further information about the case study activities in Italian can be found here

For more information about this RECARE experiment, please contact Francesco Morari This email address is being protected from spambots. You need JavaScript enabled to view it.

Geographical description

VenetoThe study area is located in the low Venetian plain (see right) and is characterized by sedimentary loamy soils with shallow groundwater (<2 m). The local climate is sub-humid, with annual rainfall of about 850 mm. Temperatures increase from January (minimum average: 1.5 °C) to July (maximum averag 27.2 °C). Soil organic matter (SOM) content is strongly affected by the peculiar texture (low physical protection) and climatic conditions, and usually range from 10 to 20 g.kg-1 in the top layer. The altitude of the Veneto Region varies from ca. 3,300 m of the Dolomites Mountain to the sea level, from north to south. The low Venetian plain is generally flat and does not exceed 50 m a.s.l. (see below). The area surrounding the Venice lagoon (1,240 km2) is even lower, (2 m below the sea level) and currently cultivated due to land reclamation since 1st century BC.

Main soil threat

The main threat considered is the loss of SOM in mineral soils. It causes both GHG emissions and a worsening of soil functions (e.g. soil nutrient supply, hydraulic properties), pushing farmers to rely on external chemical input. In the last fifty years, SOM in northeast Italy decreased at rates ranging from 0.02 to 0.58 t C.ha-1.y-1 year as a consequence of the intensification and simplification of cropping systems (e.g. monoculture) and the uncoupling of crop and livestock production. Most recently, the removal of crop residue for bioenergy production raises further concern about its potential impact on SOM evolution.

Application of EU conditionality measures (i.e. mandatory crop rotations) has had only a marginal effect on SOM recovery, while other voluntary measures supported by the Regional Government (e.g. input of organic amendment, no-tillage) showed low acceptance by the farmers. Indeed, implementation of measures has been hindered by: a) technical, logistic and economic constraints (e.g. distance between amendment source and potential users); b) farmer's cultural diffidence; and c) uncertainties of their bio-physical effectiveness, due to a large variability in pedo-climatic conditions which strongly affect the interaction between organic input and carbon cycle

fig143Typical agricultural landscape in the low Venetian plain.

Other soil threats

The region also suffers loss of Used Agricultural Area (UAA) due to excessive urbanisation which affects mainly the fertile soils of the Venetian plain (Tempesta, 2008). In the last decades Veneto Region has undergone rapid industrial growth which has strongly sharpened competition for natural resources. It has been estimated that during 1970-2010, 15% of cultivated land in Veneto plain (c.a. 120,000 ha) was affected by soil sealing, decreasing the potential agricultural production and increasing the frequency of flood events. Intensive cultivation systems and Confined Animal Feeding Operations (CAFOs) also have a strong impact on the environment, causing problems such as nutrient leaching, GHGs emissions and loss of biodiversity.

fig141

 Location and Digital Elevation Model (DEM) of the Veneto Region (Source: SRTM)

Natural environment

Geology & Soils
The composite geology of the Veneto region is the result of a series of geological events that took place in the course of thousands of years: the typical dolomitic conformation of the northern area was deposited on rhyolitic ignimbrites and andesitic, rhyolitic and dacite lava, which in turn were overlapped on the crystalline basement that was formed ca. 400 million years ago (Regione Veneto, 1990). The large number of faults indicates an intense tectonic activity and dislocation in the region that affected the subsidence and formation of the Venetian plain by causing the accumulation of alluvial and coastal deposits. The Venetian plain was formed in its southern part by the sedimentary action of Po River and in the northern one by the sedimentary action of Adige, Brenta, Piave and Tagliamento rivers. In particular, the low Venetian plain is characterised by sandy and silty-clay deposits due to the minimal slope of the land (down to 1‰) that sensibly reduces the transport capacity of the water courses. Accordingly, the soils of the low Venetian plain were formed by and evolved from the alluvial materials deposited over the millennia with the exception of the coastal area, where a consistent part of the soils is formed by sandy sediments of marine origin. According to the World Reference Base (Regione Veneto, 2005) the major soils of the low Venetian plain are Calcisols and Cambisols (below, left), characterised by low natural fertility due to low organic matter and carbon contents and low cation exchange capacity, while they contains excessive amounts of calcium carbonates (CaCO3). They are often characterized by shallow groundwater levels (< 2 m). The most relevant natural limitation of these soils is the lack of organic material that is strongly affected by the peculiar texture (low physical protection) and climatic conditions, and usually ranges from 10 to 20 g kg-1 in the top layer.

fig142

font-size: 8pt;">Soil groups and materials (WRB) (left) and Land Use in the Case Study (right) (Source: JRC).

Land Use
Farming covers about 57% of the Veneto region territory, while the remaining area is occupied by woodlands (29%), urban areas (8%) and wetlands (6%). Agricultural areas are mainly concentrated in the Venetian plain (92%), comprising of cereals (maize, wheat), soybean, and horticulture cultivations (Table 14.1). Maize, representing ca. 80% of the total national production, allows Veneto to be the leading Italian region in the sector. Croplands are generally irrigated where the shallow water table does not contribute to groundwater irrigation.


Several phytogeographical, geomorphological, climatic and anthropogenic factors have contributed to the great heterogeneity of the Veneto landscapes. The Veneto region primarily includes the alpine (in the northern part) and continental biogeographic areas (in the central and southern part), although the vegetation was also sensitive to the geological substrate. The sedimentary substrates that dominate in the Venetian plain, allow the development of different ecosystems as they are characterized by limestones and dolomite rocks as well as marlstones. Nevertheless, the intense anthropogenic activity has deeply modified the landscape and the vegetation. The typical vegetation of the low Venetian plain used to include oak and hornbeam forests, predominantly dominated by Quercus robur and attributable to Asparago tenuifolii-Quercetum roboris. Now black locust (Robinia pseudoacacia L.) and poplar trees (e.g. Populus nigra L.) are more frequently met as a consequence of degraded areas and tree plantations standing between a complex system that mixes urban, agricultural and industrial areas. Close to the Venice lagoon, the influence of the sea and of lagoons and dune ridges favour the formation of a coastal area that includes typical plant communities such as Cakiletea maritimae, Ammophiletae and Quercion ilicis.

Agricultural land use Area %
Cereals 54.8%
Industrial crops 13.7%
Vineyards 6.8%
Horticulture 2.6%
Orchards 2.9%
Tree plantations 10.6%

 Main crops of the Venetian plain (ISTAT, 2010).

Climate

The continental climate of the low Venetian plain is sub-humid, with annual rainfall of about 850 mm. Temperatures increase from January (minimum average: 1.5 oC) to July (maximum average: 27.2 oC). The rainfall distribution (Figure 14.4) during the year is characterised by a maximum in June (ca. 100 mm) and minima in winter (50-60 mm per month from December to February). On average, relative humidity varies relatively little during the year, the maximum values being around 90% in winter and 75% in summer. The reference evapotranspiration (ET0) for the low Venetian plain is 945 mm in the median year, but can reach above 1,000 mm per year at a frequency of 20%. ET0 reaches a peak in July, when it is close to 160 mm (ca. 5 mm d-1) on average, exceeding rainfall in the period April-September. Rainfall deficit increases from June to September when it is close to 250 mm (Giardini, 2004).

fig144

Average annual (left) and mean monthly (right) precipitation and temperature of the low Venetian plain.

Hydrogeology

The Veneto region has a dense river network that includes some of the largest Italian rivers. In the south, the Po River flows through the plain and into the Adriatic Sea forming a large delta. The Adige River and its basin are just north of the Po River, expanding to about 12,000 km2, followed by the Brenta and Piave basins in the eastern part of the region. In the low Venetian plain, an unconfined shallow groundwater (ca. 1-3 m depth) is overlapped to confined aquifers (Provincia di Venezia e ARPAV, 2008). Shallow groundwater is located in sandy or silty layers, rarely on gravel layers.

Drivers and pressures

The main pressures on the soil resource concern the intensive agricultural practices that are particularly applied in the mineral soils of the low Venetian plain, in turn characterised by low natural SOM content. The simplification of cropping systems (e.g. monoculture) and the uncoupling of crop and livestock production have deteriorated the soil quality by reducing, for example, the external input of organic amendments.

The introduction of innovative and efficient agricultural technologies in arable lands has been hindered by the relatively small average size of farms in Veneto. Indeed more than 55% of the farms have an area smaller than 5 ha while only ca. 5% is larger than 30 ha. The sector is also strongly affected by fluctuating commodity prices, especially maize, that have led to a reduction of incomes and have forced farmers to rely on agricultural contractors. Mycotoxin contamination of maize kernels is another factor which has a strong influence on commodity price, especially in high intensive cultivation systems. Low farm incomes and inadequate generational turnover drove small farmers out of the market, especially in marginal areas (i.e. hilly and mountainous areas) where the phenomenon has been associated to land abandonment.

As observed in other European Countries, alternative use of the soil, such as for bioenergy crop production, conflicts with the traditional land use. It was estimated that in 2010 bioenergy crops were grown in more than 11,000 ha as follows: rapeseed (4,800 ha) and soybean (3,400 ha) for biodiesel and maize (1,700 ha) and sorghum (5,000 ha) for biogas (Regione Veneto, 2014). Most recently, the removal of crop residue for bioenergy production raises further concern about its potential impact on SOM evolution.

Status of soil threat

The most relevant limitation of the soils located in the low Venetian plain of the Veneto region is the lack of soil organic matter (SOM) that is strongly affected by their natural texture (low physical protection) and climatic conditions. Soil organic carbon (SOC), mainly stored in organic matter components, is generally lower in lowlands (1-2%) than in hilly and mountainous areas (2-5% or more) (below left). Moreover, SOC content is often less than 1% in Rovigo, Verona, Venezia and Padova districts (ARPAV, 2010), especially where intensive agriculture is practiced in the large scale and the input of organic material is poor or missing. In the last fifty years, SOM in northeast Italy decreased at rates ranging from 0.02 to 0.58 t C ha-1 y-1, enhancing the abovementioned natural low organic matter content of the low Venetian plain (below right).

fig145

 Left: SOC content (%) in the Veneto region (ARPAV, 2010), Right: SOC change from 1962 to 2012. FYM: farmyard manure (Berti el al., 2015).

Effects of soil threat on soil functions

The following table ranks the effects of SOM decline on the soil functions in the Veneto.

Functions of soilExplanationEffect
Food and other biomass production Improvement of soil physical, chemical and biological properties, source of macronutrients M
Environmental interaction: storage, filtering, buffering and transformation (including carbon pool) soil C sink capacity, complexion of mineral cations, water retention, interaction with xenobiotics H
Biological habitat and gene pool SOM is the main source of energy for the decomposer organisms, hormone-like activities H
Physical and cultural heritage    
Platform for man-made structures: buildings, highways    
Source of raw materials    

Effects of loss of soil organic matter on soil functions (H: High; M: Medium)

WOCAT Maps 

Maps on the current state of land use, soil degradation and soil conservation in the case study area have been produced using the WOCAT (World Overview of Conservation Approaches and Technologies) methodology

The steps of this process are as follows:

1) The area to be mapped is divided into distinctive land use systems (LUS).
2) The team gathers the necessary data on soil degradation and conservation for each LUS using a standardised questionnaire, in close consultation with local land users, and supported where possible by remote sensing or field data.
3) For each LUS, the soil degradation type, extent, degree, impact on ecosystem services, direct and indirect causes of degradation, as well as all soil conservation practices, are determined.
4) Once collected, the data is entered in the on-line WOCAT-QM Mapping Database from which various maps can be generated.

Following the principles of all WOCAT questionnaires, the collected data are largely qualitative, based on expert opinion and consultation of land users. This allows a rapid and broad spatial assessment of soil degradation and conservation/SLM, including information on the causes and impacts of degradation and soil conservation on ecosystem services.

More details about the methodology used to produce these maps and their interpretation can be found here.

Land Use (click on maps to expand)

 Italy Veneto land use typesS Italy Veneto area trend land use systemS  Italy Veneto trend in land use intensityS

Soil Degradation

The degree of degradation reflects the intensity of the degradation process, whilst the rate of degradation indicates the trend of degradation over a recent period of time (approximately 10 years).

 Italy Veneto dominant types of soil degradationS Italy Veneto degree of degradationS  Italy Veneto rate of degradationS

 Conservation Measures

The "effectiveness" of conservation is defined in terms of how much it reduces the degree of degradation, or how well it is preventing degradation.  The Effectiveness trend indicates whether over time a technology has increased in effectiveness.

Italy Veneto dominant conservation measuresS Italy Veneto effectiveness of conservation measuresS  Italy Veneto conservation effectiveness trendS

RECARE data repository

Data collected from the case study area for the project are held in a repository on the European Soil Data Centre (ESDAC) website hosted by Joint Research Centre (JRC).  Below is a list of the data held.

  • General info
  • Precipitation
  • Temperature
  • Soil Parameters
  • Soil Erodibility
  • K-Stoniness
  • Organic carbon content
  • Rainfall Erosivity
  • PESERA
  • Topsoil Organic Carbon
  • Wind Erodible Fraction

To access the data click HERE (currently only accessbile with  EUECAS login details)

Administrative and socio-economic setting

From an economic point of view, the Veneto region is the third largest region in Italy for wealth production, contributing 9.4% of the national GDP (below right). In spite of the economic crisis, the Veneto region has one of the highest rates of employment in Italy (63.3% in 2013), while the unemployed were 7.6% of the workforce (see below). The Veneto region has a strong industrial vocation: the share of the wealth produced by the industry is 31.6%, although it decreased over the past 15 years, while the tertiary sector increased by of 66.5% from 2000 to 2012 (Regione Veneto, 2013). The agricultural sector (1.9% of GDP) is progressively integrated in the agri-food that develops a similar surplus value. The majority of CAFOs in the region is in the Venetian plain (77%), amounting about 1 million livestock units. CAFOs are particularly relevant in the northern part of the plain due to its abundance in water resources (ISTAT, 2010). Another important sector is fishing and aquaculture, representing the 9% of the national GDP. More than a third of the regional GDP comes from exports. In 2013, exports from the Veneto region were 13.5% of the national total, amounting to 52.6 billion €, and agriculture and agri-food sectors contributed 9% of the total. There are increasingly fewer agricultural enterprises and these are on average progressively becoming larger. The average utilised UAA has increased by over 40% just in the last ten years both in Veneto and in Italy, reaching 6.8 and 7.9 ha respectively, while the number of both Veneto and Italian companies has fallen by 32.4%. In 2010, the sole proprietor enterprises operated by landowners with exclusively owned land of small dimensions and heavily centred on the family of the farm manager were still the most widespread form; moreover, half of the Veneto farm managers are over 60 years old and other profit-making activities connected to farming are not widespread. The arrival of young people in the agriculture (more than 1,800 young farmers have started a farming activity during 2007-2013) is bringing a strong transformation component. The impulse for renewal is considerably large, although the farm managers under 40 years old represent just 7% of the Veneto enterprises (Regione Veneto, 2014).

fig146

Population in Veneto region (left) and GDP per capita trends for Italy and the Euro Area (right)

 

fig147

Employed dynamics in Veneto region and employed distinction for field of work

Management options

The Regional Government is the organism that can dictate the policies of improving the environmental quality. In the context of EU and national objectives and taking into account the local needs, strengths and weaknesses, the Veneto region government has defined strategies aiming to improve the local environment (Regione Veneto, 2007).

European agro-environmental directives have posed different restrictions to the farmers in order to mitigate their impact on water and soil resources. For instance, around 350,000 ha have been declared as Vulnerable Zones according to the Nitrate Directive, capping the organic nitrogen input and in turn the whole food productive chain. Within the last Rural Development Plan (2007-2013), expected results were defined in terms of area under successful land management contributing to ca. 132,000 ha for biodiversity and high nature value of farming and ca. 129,000 ha for water quality improvement. In this context, measures were introduced with the aim of enhancing water quality, protecting soils from degradation, safeguarding biodiversity, improving animal welfare, preserving and increasing agro-forestry area with high nature value and finally strengthening the effects of agro-forestry activities that reduce GHG emissions and improve air quality. In particular, during the period 2007-2013, the agro-environmental measures under the Rural Development Plan were supported by 79% of its programmed expenditure. Specific agro-environmental measures to enhance soil and environmental quality include: i) input of organic amendments; ii) application of conservation agriculture practices, such as no-tillage and the use of cover crops; iii) organic agriculture and iv) the creation of buffer strips. Application of good agricultural and environmental conditions (GAECs) under Cross Compliance (e.g. mandatory crop rotations) has had only a marginal effect on SOM recovery, while the voluntary Regional Government ones (e.g. input of organic amendment, no-tillage etc.) showed low acceptance by the farmers. Indeed, implementation of measures has been hindered by: i) technical, logistic and economic constraints (e.g. distance between amendment source and potential users); ii) farmer’s cultural diffirence; iii) uncertainties of their bio-physical effectiveness, due to a large variability in pedo-climatic conditions which strongly affect the interaction between organic input and C cycle. Measures financed by the Regional Government are still valid short term practices to enhance soil quality.

Low acceptance of the voluntary Regional Government measures clearly demonstrates the low awareness of the farmers for the soil threat. A rethinking of the present agriculture productive models should be considered in order to suggest alternative models aiming to increase the efficiency of the farm in terms of nutrient and carbon cycles and energy use. Farmer education, dissemination and participation are also necessary to identify the potential risk associated with the SOM loss and implement viable alternatives.

Biochar application has been also suggested as a measure to increase stable SOC content.

Stakeholder involvement

The relevant end users and stakeholders include;

  • Agro-Environmental Bureau, Regional Government, Regione Veneto,
  • Veneto Agricoltura, Regional agricultural extension service, Regione Veneto,
  • Confagricoltura Veneto, regional farmer association,
  • Coldiretti Veneto, regional farmer association,
  • Confederazione Italiana Agricoltura Padova, regional farmer association.

In the first phase of the project, a stakeholder platform will be established with farmer associations, extension service and policymakers. Preliminary meetings will be organized to identify optimal strategies to restore soil functions. The results obtained in the study sites and potential constraints will be analyzed in periodical meetings and field days organized in cooperation with other WPs. A dedicated web platform will be built to share information among stakeholders with a blog to discuss demonstration and monitoring relevancies and to have a continuous feedback.

Gender and stakeholder workshops

The first workshop in Veneto had 16 participants of whom two were women (+4 University staff members). They were from the regional government and the agricultural private sector. Men were landowners, land managers, private sector advisors to public enterprises and providers of information. In the second workshop with 13 participants still two women attended (+4 University staff members), neither was a landowner but both were involved in the decisions about the land use. Both women said their role would not change with a change in land use. In the evaluation, it was generally ignored that there are typical roles for men and women in the region. It was mentioned in the questionnaire that men are more pragmatic and women more sensitive to changes. All participants admitted that they want to change the land use to improve the soil and that they would invest in more sustainable land management.

References

ARPAV, Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto, 2010. Mappa CO – anno 2010. http://www.arpa.veneto.it/ (26/09/2014).

ARPAV, Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto, 2012. Carta dell'Altimetria. http://www.arpa.veneto.it/ (26/09/2014).

Berti A., Dal Ferro N., Polese R., Simonetti G., Morari, F., 2015. Modelling soil carbon evolution in a long-term field experiment. Contribution of the refractory root biomass. In preparation.

Giardini L., 2004. Productivity and Sustainability of Different Cropping Systems. 40 years of Experiments in Veneto region (Italy). Patron editore, Bologna.

ISTAT, Istituto Nazionale di statistica, 2010. 6° Censimento generale dell’agricoltura 2010. Caratteristiche strutturali delle aziende agricole. Dipartimento per i censimenti e gli archivi amministrativi e statistici, Roma.

Provincia di Venezia e ARPAV, 2008. I Suoli della provincia di Venezia. ARPAV - Osservatorio Regionale Suolo, Castelfranco Veneto.

Regione Veneto, 1990. Carta geologica del Veneto, scala 1:250000.Regione Veneto, Segreteria Regionale per il Territorio, Venezia.

Regione Veneto, 2005. Carta dei Suoli del Veneto alla scala 1:250000, 3 vols. ARPAV - Osservatorio Regionale Suolo, Castelfranco Veneto.

Regione Veneto, 2007. Programma di sviluppo rurale per il veneto 2007-2013. Dipartimento Agricoltura e Sviluppo Rurale, Venezia.

Regione Veneto, 2013. Statistical Report 2013 - Transformation and development. http://www.regione.veneto.it/web/statistica (26/09/2014).

Regione Veneto, 2014. Italy - Rural Development Programme (Regional) – Veneto. Dipartimento Agricoltura e Sviluppo Rurale, Venezia.

Tempesta T., 2008. Consumo di suolo o consumo di ambiente? Rivista di Economia Agraria 4,453-468.

Case Study Experiment - increasing or maintaining soil organic matter

The RECARE researchers tested the effectiveness of various measures to increase or maintain soil organic matter.  The main experiment involved grass undersowing in maize.  Other experiments included the use a manure separator that differentiates between crops and fields with different soil quality and the application of humic acid.
Grass undersowing maize
Grass undersowing in maize

Final Results

  • Grass undersowing in maize fields is expected to result in 0.5% extra soil organic matter (SOM) after 30 years, and also a little more production of grass in years with grass cropping. But since the measure was only started in 2014, the result is still unknown. Conversations with four farmers revealed that the SOM content has remained stable or slightly increased, and that the bearing capacity of the soil has improved.
  • Average nitrate concentration in the upper groundwater in the area fluctuated around the EU-standard of 50 mg/l: in 2014 and 2017 it was above and in 2005 and 2016 below the standard.
  • Farmers experienced variable results from grass undersowing, depending strongly on the weather, with good growth of the grass cover in wet years, but competition for water with the maize crop and no grass growth in dry years. Farmers frequently experienced poor grass cover.
  • Drawbacks of the measure mentioned by farmers are that the undersowing may cause damage to the standing maize crop and in the headlands of the fields and that the sowing is a difficult task since it needs to be done at the right places and in the right period. It is difficult to perform in small parcels, and the weed control is more difficult.
  • Farmers also indicate that grass undersowing is not effective in a grain maize crop, where only the maize cobs are harvested and the rest of the plant is frittered, thereby suffocating the undersown grass.
  • Grass undersowing was evaluated by farmers and residents to foster regulating ecosystem services, namely the increase of the buffer function for organic matter and nitrogen and the bearing capacity of the soil. Also, cultural ecosystem services were found to be improved when fields remain green after the harvest of the maize crop, instead of showing brown stubble.
  • However, the provisioning ecosystem services that were foreseen as a result of this measure (increase in feed crop yield and groundwater production) were not mentioned by the farmers as a benefit.

Further details about this experiment can be found in the fact sheet HERE (NL) and in the project report HERE

For more information about this RECARE experiment, please contact Simone Verzandvoort This email address is being protected from spambots. You need JavaScript enabled to view it.

Geographical description

Olden Eibergen

The Case Study area is located in the eastern part of The Netherlands. In general, soils are sandy to loamy in the region. The groundwater table varies between 0.5 to 2 m below surface in summer time. The area has two intake points of drinking water. Levels of Betazon, methylchlorophenoxypropionic acid (MCPP) and sulfite have risen in the intake water over the last decade. Land use is mixed with agriculture combined with hedges, small forests and small streams. Agriculture, in general, is small scale but relatively intensive in terms of livestock densities.

 Main soil threat

OldenEibergenLandscape

The case study area 'Olden Eibergen' is characterized as a multifunctional rural area with a combination of agricultural and natural land use, and two drinking water intake areas. The main soil threat in this area is the gradual loss and decline of soil organic matter stocks. According to farmers on average agricultural fields have lost 10 to 30 tons of organic matter in the last 10 years. This threatens the agricultural quality of the soil as well as the potential of the soil to buffer leaching of nutrients and residues of crop protection. In the long term, agricultural productivity will fall, costs of agricultural inputs such as manure and crop protection will increase and the extra upstream costs for cleaning drinking water following intake of water will rise.

The loss of soil organic matter is due to a combination of factors, such as long-term and continued monocultures of maize on specific parcels, intensive seed potato cropping in the area, strict(er) manure legislation directed at minimizing nitrogen and phosphorus application to fields and limited inputs of exogenous organic matter. Some farmers try growing green fertilizer crops after the harvest of maize, whilst others try adopting alternative tillage techniques. Yet, farmers have only recently been confronted with the impact of decreasing organic content of their fields and have started to fully realize the implications of this for future production and income. Since the 1980's, enough organic matter was applied to fields with abundant animal manure. Now, the challenges of the Case Study area are to secure clean drinking water intake for the long term in combination with sustained agricultural production in the region. Knowledge gaps have been identified and include: how to better plan and disperse the manure at: i) farm level, or ii) regional level by exchanging manure or organic matter between different farm types (arable, goat, pigs, cow farms). Other ways to combat soil deterioration include introducing new varieties of crops such as highly productive grass species or early ripening maize that can be combined with post-harvest (second) catch crops. Technical solutions such as manure processing (thickening), or applying concentrated soil organic matter by-products from the drink water intake and cleaning (humine acids) will be considered.

Other soil threats

Other soil threats result from high input levels of nutrients due to intensive livestock farming in the area. Phosphate and nitrogen levels are in general high, due to a historically high input of animal manure (RAAP, 2008; Gelders Genootschap, 2012). However, due to reduced soil productivity as a result of low soil organic matter content, the farmer is sometimes forced to compensate stress periods in the growing season (dry or wet periods) with external inputs such as additional fertilizer, crop protection or irrigation. This exerts additional pressure on the system. Other soil threats include moisture deficits, contamination of groundwater and soil compaction.

fig131
Location and Digital Elevation Model (DEM) of Olden-Eibergen (SourceSRTM).

Natural environment

Geology & Soils
The soils in the Olden-Eibergen Case Study area are developed in cover sands and clayey and loamy sediments deposited by the small stream of Berkel (Figure 13.2). Most soils are podzols or cambisols; nutrient-poor soils developed in sand. The area also has patches of anthroposols, soils enriched in Medieval times with manure and organic residues. Phosphate and nitrogen levels in these soils are in general high. 

fig132

 Soil types in the Olden-Eibergen Case Study area (left); (right, source: Stiboka, 1979)

Land Use

The Case Study area “Olden Eibergen” is a multifunctional rural area with a combination of agricultural and natural land use. The area is around 1,000 ha, of which 700 ha are used for agriculture with rotations consisting of potatoes, wheat and maize crops. The remaining surface is in use for small patches of forest, tree-lined field borders, recreational spaces and the homesteads of houses and farms. 40 agricultural enterprises own land in the area, as well as several 100 ha outside the area. The agricultural enterprises are small compared to the Dutch farms in the western part of the country (in terms of productivity and acreage), but the livestock density is large compared to the Dutch average.

fig133 Left: typical land use in the Case Study area of Olden-Eibergen: pasture with grazing cows and maize fields, intersected by tree-bordered roads. Picture: S. Verzandvoort;
right: Podzolic soil in pasture land. Picture: S. Verzandvoort 

Climate

Climatological information on the study site is derived from the meteorological stations of Hupsel and Borculo, at respectively 2 and 15 km distance from the Case Study (Figure 13.4). Mean monthly temperature varies between 2 and 17°C. The long-term mean annual precipitation is between 800 and 825 mm, with the lowest amounts in spring, and the highest in autumn. The long-term average annual precipitation deficit is between 200 and 240 mm.

 fig134

Average annual (left, source Royal Netherlands Meteorological Institute – KNMI at Twenthe)
Mean monthly (right) precipitation (meteorological station Borculo) and temperature (meteorological station Hupsel).

 Hydrogeology

The groundwater table varies between 0.5 to 2 m below surface in summer time. The area has two intake points of drinking water (Figure 13.5, left). Levels of the pesticides Bentazon and MCPP have incidentally exceeded the norms for drinking water production between 1985 and 2009 in the water abstracted from the groundwater over the last decade (Vitens) (Provincie Gelderland, 2011).

Drivers and Pressures

The loss of soil organic matter in the area is caused mainly by the following drivers and pressures: long term monocultures of maize, intensive seed potato cropping, strict manure legislation directed at minimizing nitrogen and phosphorus application to the fields, and limited inputs of exogenous organic matter. This has caused a decline in production levels, problems with too dry and too wet soils, and rising nitrate concentrations in the groundwater.

Monoculture of maize is performed on fields located on podzolic soils low in soil nutrients (‘veldpodzolgronden’), at larger distance of the homesteads. The use of pig manure on these fields (low in organic matter compared to other types of manure) contributed to the decline in organic matter compared to other fields. The stricter manure legislation since January 2014 derives from the European Nitrates Directive. This legislation forces farmers to process or export the manure produced on their farms above the threshold.

Status of soil threat

The Province of Gelderland is currently implementing a sustainable resource management policy, and supports projects on nutrient use efficiency, like the project Gezond Zand (2010-2014) (Rienks and Leever, 2014). All farmers participating in the Gezond Zand project collected information on the organic matter content of their fields in 2000 and 2010. The soil organic matter content decreased in this period on the fields with continuous maize cultures or other arable cultures, mostly situated on the “field podzol” soils, that are inherently poor in nutrients, and that mainly receive pig manure. The decrease was up to 5% in some fields (below right) (Rienks and Leever, 2014).

fig135

Left: Areas with protected groundwater for drinking water supply. The purple line depicts the outline of the study area. Source of data: ROM3D, Gezond Zand.
Right: Soil organic matter decline between 2003 and 2010. Source data: ROM3D and the farmers participating in the Gezond Zand project.

WOCAT Maps

Maps on the current state of land use, soil degradation and soil conservation in the case study area have been produced using the WOCAT (World Overview of Conservation Approaches and Technologies) methodology 

The steps of this process are as follows:

1) The area to be mapped is divided into distinctive land use systems (LUS). 2) The team gathers the necessary data on soil degradation and conservation for each LUS using a standardised questionnaire, in close consultation with local land users, and supported where possible by remote sensing or field data. 3) For each LUS, the soil degradation type, extent, degree, impact on ecosystem services, direct and indirect causes of degradation, as well as all soil conservation practices, are determined. 4) Once collected, the data is entered in the on-line WOCAT-QM Mapping Database from which various maps can be generated.

Following the principles of all WOCAT questionnaires, the collected data are largely qualitative, based on expert opinion and consultation of land users. This allows a rapid and broad spatial assessment of soil degradation and conservation/SLM, including information on the causes and impacts of degradation and soil conservation on ecosystem services.

More details about the methodology used to produce these maps and their interpretation can be found here.

Land Use  (click on maps to expand)

The Netherlands Olden Eibergen land use typesS The Netherlands Olden Eibergen area trend land use systemS The Netherlands Olden Eibergen trend in land use intensityS

Degradation

The degree of degradation reflects the intensity of the degradation process, whilst the rate of degradation indicates the trend of degradation over a recent period of time (approximately 10 years).

The Netherlands Olden Eibergen dominant types of soil degradationS The Netherlands Olden Eibergen degree of degradationS The Netherlands Olden Eibergen rate of degradationS

Conservation measures

The "effectiveness" of conservation is defined in terms of how much it reduces the degree of degradation, or how well it is preventing degradation. The Effectiveness trend indicates whether over time a technology has increased in effectiveness.

The Netherlands Olden Eibergen dominant conservation measuresS The Netherlands Olden Eibergen effectiveness of conservation measuresS The Netherlands Olden Eibergen conservation effectiveness trendS

RECARE data repository

Data collected from the case study area for the project are held in a repository on the European Soil Data Centre (ESDAC) website hosted by Joint Research Centre (JRC).  Below is a list of the data held.

  • General info
  • Precipitation
  • Temperature
  • Soil Parameters
  • Soil Erodibility
  • K-Stoniness
  • Organic carbon content
  • Rainfall Erosivity
  • PESERA
  • Topsoil Organic Carbon
  • Wind Erodible Fraction

To access the data click HERE (currently only accessbile with  EUECAS login details)

 Effects of soil threat on soil functions

The table below summarises and ranks the effects of soil organic matter decline on the soil functions in Olden-Eibergen.

Functions of soilExplanationEffect
Biomass production Decline of feedstock production (hay, maize, grass) H
Environmental interactions Leaching of nitrate and pesticides to groundwater H
Gene reservoir/ Biodiversity pool Not applicable N
Physical medium Idem N
Source of raw materials Idem N
Carbon pool Decline due to soil organic matter decline H
Cultural heritage Patterns of SOM development inform about the cultural history of the area. The effect is moderate since the enriched soils are depleted at a smaller rate than the soil without historical enrichment. L

Effects of soil organic matter decline on soil functions. (L: Low; H: High; N: None)

Administrative and socio-economic setting

“Olden Eibergen” is located in Achterhoek (NUTS3: COROP14), in the Province of Gelderland (NUTS 2: NL22). The farmland in the area is owned or rented by farmers. The most important policy and legislation that influence farmers’ choices in land management include the national manure legislation, resulting from the EU Nitrogen Directive. This legislation limits the amount of manure that farmers may apply to their field to a maximum per enterprise. However, manure availability is unevenly distributed among farmers. The ambition of the sustainable land management approach taken by the farmers and the Foundation HOEDuurzaam is to enable the exchange of manure between farmers.

The Common Agricultural Policy also influences the choices of the farmers, since due to the disappearing of the milk quota as off 1-4-2015, the production will be increased. Nevertheless, the recent abolishment of the milk quota has not driven the decline of organic matter during the period considered. The SLM measures currently implemented by the farmers are eligible for subsidy from the CAP for good agricultural practices under pillar III, because of the foreseen impacts on water quality, soil quality and climate. The Water Framework Directive is also influential since better functioning soils will lead to reduced impact on local and regional water systems.

Based on the environmental and sustainability policy of the Province of Gelderland, farmers also receive subsidies for the land management measures.

 

fig136

Population of the municipality Berkelland, The Netherlands (left, Source: STATLine, Central Statistics Agency of The Netherlands);
GDP per capita trends for the Euro Area, the Netherlands and the regional economy (Sources: EUROSTAT, STATLine, Central Statistics Agency of The Netherlands (accessed 6-4-2015))

 Management options

The land management measures currently implemented in response to declining organic matter include the growing of green fertilizer crops after the harvest of maize. Other farmers try adopting alternative tillage techniques. Yet, farmers only recently have been confronted with the impact of decreasing organic content of their fields and have started to fully realize the implications of this for future production and income. Since the 1980’s, enough organic matter was applied to fields with abundant animal manure. Now, the challenges of the Case Study area are to secure clean drinking water intake for the long term in combination with sustained agricultural production in the region. Knowledge gaps have been identified and include: how to better plan and disperse the manure at: i) farm level, or ii) regional level by exchanging manure or organic matter between different farm types (arable, goat, pigs, cow farms). Bridging these gaps will provide additional solutions to the users. Other ways to combat soil deterioration include introducing new varieties of crops such as highly productive grass species or early ripening maize that can be combined with post-harvest (second) catch crops. Technical solutions such as manure processing (thickening, separation) or applying concentrated soil organic matter by-products from the drink water intake and cleaning (humic acids) are in the experimentation phase.

Stakeholder involvement

Relevant end-users and local stakeholder groups include;

  • 20 to 30 farmers in the area

  • Vitens drinking water company

  • Local sustainable energy company using biomass as green energy input

  • Municipality of Berkelland

  • Regional Water Board Rijn & IJssel

  • ROM3D advising company

The farmers will be asked to look up field samples they have available of their soils. For each farm a soil organic content map will be made of the current and historical situation. Based on these maps, a plan will be discussed between farmers and ROM3D consulting on how to improve on the longer term. For each parcel of land, measures will be agreed upon with the farmers and monitoring will start. Vitens drinking water company, the Municipality of Berkelland and the regional Water Board will make available organic matter from their own land such as mowed grass and reeds. These will be processed into organic matter for the farmer's fields. Furthermore, farmers will implement measurements such as adapting their crop rotation, zero tillage, and make use of green fertilizers. Not only at parcel level but also at farm and regional level, better dispersion of available organic material will occur.

References

Rienks, Willem en Leever, Henk, 2014. Gezond Zand. Met een verbeterde bodemkwaliteit naar een betere waterkwaliteit Haarloseveld en Olden Eibergen. Stichting Marke Haarloseveld Olden Eibergen en omstreken. HOEduurzaam, www.hoeduurzaam.nl

Gelders Genootschap, 2012. BERKELLAND BESCHREVEN – Cultuurhistorische gebiedsbeschrijving. 162 pp.

Provincie Gelderland, 2011. Gebiedsdossier Haarlo - Olden Eibergen. Aequator and Royal Haskoning BV. 56 pp.

RAAP, 2008. RAAP-rapport 1748, P 28-29.

W.A. Rienks en H. Leever, 2014. Gezond Zand – organische stof als sleutel voor een vruchtbare bodem en schoon water. ROM3D en Stichting Marke Haarlose Veld Olden Eibergen.

Stiboka, 1979. Bodemkaart van Nederland schaal 1 : 50 000 - Toelichting bij de kaartbladen 34 West en 34 Oost Enschede - 35 Glanerbrug. Wageningen, Stichting voor Bodemkartering

Case Study Sites

 Click on the map below to find out more about RECARE's case study sites
Case Studies

Project Partners

ABOUT US

RECARE was a multidisciplinary research project of 27 different organisations that assessed the threats to Europe's soils and identified innovative solutions to prevent further soil degradation.  The project ran from 2013 - 2018.

Academic Contact
Professor Coen Ritsema 
Wageningen University
E: coen.ritsema[AT]wur.nl

Media Contact
Dr Matt Reed
E: mreed[AT]glos.ac.uk

Funding

Funded by the European Commission FP7 Programme, ENV.2013.6.2-4 ‘Sustainable land care in Europe’.

EU grant agreement: 603498.

Project officer: Maria Yeroyanni.

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