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An investigation was made of the fracture risk to buried ceramic pots and bones from the subsurface pressures generated by agricultural operations. A method for generating subsurface pressures at 0.25 m depth in a soil bin was developed and used to explore fracture failure of modern replicates of ceramic pots corresponding to different archaeological periods and aged medieval human bone. Application of conductive traces to the objects' surfaces allowed detection of fracturing in real-time without excavation. Predictive models relating fracture of objects to subsurface pressure application were developed by relating the probability of fracture to observed survival statistics at increasing subsurface pressures. Subsurface pressures of above 100 kPa were sufficient to fracture the more fragile pots at a probability level of 90%. The lowest subsurface pressure causing bone fracture was 280 kPa; however, no relationship was observed between subsurface pressure and bone fracture, probably due to variation in bone material. The subsurface pressures generated and applied are within the range reported from field measurements during typical agricultural operations. They indicate that measures to control the generation of subsurface pressures would be necessary to mitigate risk of harm from agriculture to buried archaeology; for example, via low-pressure tyres, tracks and appropriate tillage. [ABSTRACT FROM AUTHOR]

Resources for achieving better soil protection are limited and need to be effectively targeted. Spatial variability is high for soil types and related quality and for the risk of degradation because of the threats of organic matter decline, erosion, compaction and salinization. A framework is presented for mapping priority areas for soil protection based on assessing where there is greater risk of degradation and evaluating its acceptability. A conceptual model is proposed which links anthropogenic hazards, threats and the risk of degradation with soil functions. It is recommended that a set of test areas is defined according to dominant soil types, and the probabilities of changes to soil properties relevant to soil functions are then estimated. The risk of exceeding a particular degradation threshold within these test areas can then be assessed and assigned to risk categories to provide the basis for the identification of priority areas. [ABSTRACT FROM AUTHOR]

Highways are major, open and dynamic sources of contaminants that present a risk to adjacent agricultural soils. Urban and peri-urban soils are particularly at risk because of a greater density of nearby highways with high traffic volumes. In developing economies, these soils support valuable food production and income, while in more developed economies there is a growing interest in urban food production. This commentary highlights the need to better characterise the sources, pathways to and impacts of highway contaminants on agricultural soils and it suggests research priorities. Soil contamination from highways includes metals, toxic organic pollutants and plastics (including large amounts of tyre dust). Contaminants from vehicle emissions and from wear of vehicles and highways are transferred to soil in airborne particulates, dust, splash, spray and runoff. Contamination is greatest near to the highway edge but can extend to >50m. Levels of metals including As, Cd, Cr, Cu, Pb, Ni, Zn in some soils adjacent to highways may exceed thresholds above which there is a potential risk of harm to food production. Elevated levels of non-threshold carcinogens (e.g. polycyclic aromatic hydrocarbons (PAHs)) in soil adjacent to highways are widely reported, with significant attribution to highway emissions. Mitigation options include improved vehicle design and performance, porous asphalt pavements, physical and vegetative barriers and better drainage. Research priorities include: (1) targeted soil monitoring to identify where highway contamination already presents a significant risk of harm to food production and to identify and assess trends in response to mitigation measures; (2) studies to assess the role of tyre particulate in transporting and releasing contaminants that are hazardous to soil (3) assessment of the risk to soil from pesticides used in highway maintenance; (4) analysis to inform a new emphasis on controlling soil pollution by innovative highway design and maintenance., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This study identifies factors affecting the fate of buried objects in soil and develops a method for assessing where preservation of different materials and stratigraphic evidence is more or less likely in the landscape. The results inform the extent of the cultural service that soil supports by preserving artefacts from and information about past societies. They are also relevant to predicting the state of existing and planned buried infrastructure and the persistence of materials spread on land. Soils are variable and preserve different materials and stratigraphic evidence differently. This study identifies the material and soil properties that affect preservation and relates these to soil types; it assesses their preservation capacities for bones, teeth and shells, organic materials, metals (Au, Ag, Cu, Fe, Pb and bronze), ceramics, glass and stratigraphic evidence. Preservation of Au, Pb and ceramics, glass and phytoliths is good in most soils but degradation rates of other materials (e.g. Fe and organic materials) is strongly influenced by soil type. A method is proposed for using data on the distribution of soil types to map the variable preservation capacities of soil for different materials. This is applied at a continental scale across the EU for bones, teeth and shells, organic materials, metals (Cu, bronze and Fe) and stratigraphic evidence. The maps produced demonstrate how soil provides an extensive but variable preservation of buried objects., (Copyright © 2015. Published by Elsevier B.V.)

Methods for the spatial estimation of risk of harm to soil by erosion by water and wind and by soil organic matter decline are explored. Rates of harm are estimated for combinations of soil type and land cover (as a proxy for hazard frequency) and used to estimate risk of soil erosion and loss of soil organic carbon (SOC) for 1 km(2)pixels. Scenarios are proposed for defining the acceptability of risk of harm to soil: the most precautionary one corresponds to no net harm after natural regeneration of soil (i.e. a 1 in 20 chance of exceeding an erosion rate of <1 tha(-1)y(-1) and SOC content decline of 0 kg t(-1)y(-1) for mineral soils and a carbon stock decline of 0 tha(-1)y(-1) for organic soils). Areas at higher and lower than possible acceptable risk are mapped. The veracity of boundaries is compromised if areas of unacceptable risk are mapped to administrative boundaries. Errors in monitoring change in risk of harm to soil and inadequate information on risk reduction measures' efficacy, at landscape scales, make it impossible to use or monitor quantitative targets for risk reduction adequately. The consequences for priority area definition of expressing varying acceptable risk of harm to soil as a varying probability of exceeding a fixed level of harm, or, a varying level of harm being exceeded with a fixed probability, are discussed. Soil data and predictive models for rates of harm to soil would need considerable development and validation to implement a priority area approach robustly., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Official frameworks for soil monitoring exist in most member states of the European Union. However, the uniformity of methodologies and the scope of actual monitoring are variable between national systems. This review identifies the differences between existing systems, and describes options for harmonising soil monitoring in the Member States and some neighbouring countries of the European Union. The present geographical coverage is uneven between and within countries. In general, national and regional networks are much denser in northern and eastern regions than in southern Europe. The median coverage in the 50 km x 50 km EMEP cells applied all over the European Union, is 300 km(2) for one monitoring site. Achieving such minimum density for the European Union would require 4100 new sites, mainly located in southern countries (Italy, Spain, Greece), parts of Poland, Germany, the Baltic countries, Norway, Finland and France. Options are discussed for harmonisation of site density, considering various risk area and soil quality indicator requirements.

Epidemiological data for esophageal cancer in the Butterworth District, Transkei, was used to calculate incidence contours which confirmed large variations within short distances (less than 5 km). High- and low-risk zones were demarcated, and a close relationship with underlying geology observed. The low-incidence zones in the study regions were underlain by dolerite intrusions, whereas higher-risk regions were on sedimentary strata. Analysis of rocks indicated that those from the higher-risk regions contain less copper, cobalt, and manganese. Soil samples were analyzed for boron, cobalt, copper, manganese, molybdenum, nickel, sodium, lead, vanadium, and zinc; the results also indicated a strong geochemical association with the disease. The concentrations of copper (P = 0.001), nickel (P = 0.001), and boron were markedly lower in the high-risk zones. Manganese, zinc, and molybdenum levels in soils also tended to be substantially lower in the high-risk zone.