Common agricultural practices such as excessive use of agro-chemicals, deep tillage and luxury irrigation have degraded soils, polluted water resources and contaminated the atmosphere. There is increasing concern about interrelated environmental problems such as soil degradation, desertification, erosion, and accelerated greenhouse effects and climate change. The decline in organic matter content of many soils is becoming a major process of soil degradation, particularly in European semi-arid Mediterranean regions. Degraded soils are not fertile and thus cannot maintain sustainable production. At the same time, the production of urban and industrial organic waste materials is widespread. Therefore, strategies for recycling such organic waste in agriculture must be developed. Here, we review long-term experiments (3-60 years) on the effects of organic amendments used both for organic matter replenishment and to avoid the application of high levels of chemical fertilizers. The major points of our analysis are: (1) many effects, e.g. carbon sequestration in the soil and possible build-up of toxic elements, evolve slowly, so it is necessary to refer to long-term trials. (2) Repeated application of exogenous organic matter to cropland led to an improvement in soil biological functions. For instance, microbial biomass carbon increased by up to 100% using high-rate compost treatments, and enzymatic activity increased by 30% with sludge addition. (3) Long-lasting application of organic amendments increased organic carbon by up to 90% versus unfertilized soil, and up to 100% versus chemical fertilizer treatments. (4) Regular addition of organic residues, particularly the composted ones, increased soil physical fertility, mainly by improving aggregate stability and decreasing soil bulk density. (5) The best agronomic performance of compost is often obtained with the highest rates and frequency of applications. Furthermore, applying these strategies, there were additional beneficial effects such as the slow release of nitrogen fertilizer. (6) Crop yield increased by up to 250% by long-term applications of high rates of municipal solid waste compost. Stabilized organic amendments do not reduce the crop yield quality, but improve it. (7) Organic amendments play a positive role in climate change mitigation by soil carbon sequestration, the size of which is dependent on their type, the rates and the frequency of application. (8) There is no tangible evidence demonstrating negative impacts of heavy metals applied to soil, particularly when high-quality compost was used for long periods. (9) Repeated application of composted materials enhances soil organic nitrogen content by up to 90%, storing it for mineralization in future cropping seasons, often without inducing nitrate leaching to groundwater.

/pdf/long-term-effects-of-organic-amendments-on-soil-fertility-a-w170id51u9.pdf

Long-term effects of organic amendments on soil fertility. A review

Assessing heavy metal sources in agricultural soils of an European Mediterranean area by multivariate analysis.

Soil health is presented as an integrative property that reflects the capacity of soil to respond to agricultural intervention, so that it continues to support both the agricultural production and the provision of other ecosystem services. The major challenge within sustainable soil management is to conserve ecosystem service delivery while optimizing agricultural yields. It is proposed that soil health is dependent on the maintenance of four major functions: carbon transformations; nutrient cycles; soil structure maintenance; and the regulation of pests and diseases. Each of these functions is manifested as an aggregate of a variety of biological processes provided by a diversity of interacting soil organisms under the influence of the abiotic soil environment. Analysis of current models of the soil community under the impact of agricultural interventions (particularly those entailing substitution of biological processes with fossil fuel-derived energy or inputs) confirms the highly integrative pattern of interactions within each of these functions and leads to the conclusion that measurement of individual groups of organisms, processes or soil properties does not suffice to indicate the state of the soil health. A further conclusion is that quantifying the flow of energy and carbon between functions is an essential but non-trivial task for the assessment and management of soil health.

/pdf/soil-health-in-agricultural-systems-1k67gevu9p.pdf

Soil health in agricultural systems

Common agricultural practices such as excessive use of agro-chemicals, deep tillage and luxury irrigation have degraded soils, polluted water resources and contaminated the atmosphere. There is increasing concern about interrelated environmental problems such as soil degradation, desertification, erosion, and accelerated greenhouse effects and climate change. The decline in organic matter content of many soils is becoming a major process of soil degradation, particularly in European semi-arid Mediterranean regions. Degraded soils are not fertile and thus cannot maintain sustainable production. At the same time, the production of urban and industrial organic waste materials is widespread. Therefore, strategies for recycling such organic waste in agriculture must be developed. Here, we review long-term experiments (3–60 years) on the effects of organic amendments used both for organic matter replenishment and to avoid the application of high levels of chemical fertilizers. The major points of our analysis are: (1) many effects, e.g. carbon sequestration in the soil and possible build-up of toxic elements, evolve slowly, so it is necessary to refer to long-term trials. (2) Repeated application of exogenous organic matter to cropland led to an improvement in soil biological functions. For instance, microbial biomass carbon increased by up to 100% using high-rate compost treatments, and enzymatic activity increased by 30% with sludge addition. (3) Long-lasting application of organic amendments increased organic carbon by up to 90% versus unfertilized soil, and up to 100% versus chemical fertilizer treatments. (4) Regular addition of organic residues, particularly the composted ones, increased soil physical fertility, mainly by improving aggregate stability and decreasing soil bulk density. (5) The best agronomic performance of compost is often obtained with the highest rates and frequency of applications. Furthermore, applying these strategies, there were additional beneficial effects such as the slow release of nitrogen fertilizer. (6) Crop yield increased by up to 250% by long-term applications of high rates of municipal solid waste compost. Stabilized organic amendments do not reduce the crop yield quality, but improve it. (7) Organic amendments play a positive role in climate change mitigation by soil carbon sequestration, the size of which is dependent on their type, the rates and the frequency of application. (8) There is no tangible evidence demonstrating negative impacts of heavy metals applied to soil, particularly when high-quality compost was used for long periods. (9) Repeated application of composted materials enhances soil organic nitrogen content by up to 90%, storing it for mineralization in future cropping seasons, often without inducing nitrate leaching to groundwater.

Long-Term Effects of Organic Amendments on Soil Fertility

/pdf/tolerable-versus-actual-soil-erosion-rates-in-europe-59wtlihpbc.pdf

Tolerable Versus Actual Soil Erosion Rates in Europe

Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection.Vol. V: Monitoring.

The State of Soil in Europe : A contribution of the JRC to the European Environment Agency’s Environment State and Outlook Report— SOER 2010

Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection.Vol. I. Introduction and Executive Summary.

Legal notice: The reports are compiled by members of the Technical Working Groups and represent the collective professional views of the authors on the scientific and technical aspects of the subject-matter. The publication does not reflect the official position of the European Commission or of the Commission's Environment Directorate-General. The authors and members of the Working Group have compiled this Report without prejudice to and without intent for personal or professional gain. The mission of the Institute of Environment and Sustainability is to provide scientific and technical support to EU strategies for the protection of the environment and sustainable development. Employing an integrated approach to the investigation of air, water and soil contaminants, its goals are sustainable management of water resources, protection and maintenance of drinking waters, good functioning of aquatic ecosystems and good ecological quality of surface waters. Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use, which might be made of the following information. Executive Summary A detailed analysis of existing monitoring, survey, GIS inventories and mapping systems in Member States and Accession Countries has allowed us to gain a comprehensive knowledge about existing systems in Europe. A possible way of systematising this very variable and inhomogeneous information is to organise the different sources of information according to three main classes: Soil maps, soil inventories and soil monitoring systems. Soil maps are available at different scales and used different classification systems and legends in all EU Member States and Accession Countries. They are the results of extensive soil surveys performed in the past 50 years in Europe, mostly for agricultural purposes. There has been no common European approach to soil survey and mapping, with different countries developing different procedures and traditions. Countries with a more structured and developed National soil survey have often developed also a National soil classification system, with measurements and parameters observed that vary greatly between different countries. Detailed soil mapping (1:50,000 or larger) is available only in some countries. Historical developments have strongly influenced the soil survey activities, with Eastern European countries developing very detailed soil maps for centralised planning purposes, but using diverging classification and measurement methods compared to Western Europe. All countries in Europe have a common 1:1,000,000 scale soil map developed jointly in the framework of the European Soil Bureau activities of the European Commission. Most of the existing soil maps are …

Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection.Vol. IV: Contamination and Land Management.

Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection.Vol. VI: Research, Sealing and Cross-Cutting Issues.

Olazabal Claudia

Papers

Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection.Vol. V: Monitoring.

The State of Soil in Europe : A contribution of the JRC to the European Environment Agency’s Environment State and Outlook Report— SOER 2010

Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection.Vol. I. Introduction and Executive Summary.

Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection.Vol. IV: Contamination and Land Management.

Reports of the Technical Working Groups Established under the Thematic Strategy for Soil Protection.Vol. VI: Research, Sealing and Cross-Cutting Issues.