Risk Assessment Methodologies of Soil Threats in Europe : Status and options for harmonization for risks by erosion, compaction, salinization, organic matter decline and landslides

摘要

The EU thematic strategy for soil protection recognizes that soil degradation through erosion,soil organic matter decline, compaction, salinization and landslides occurs in specific areas,and that these areas must be identified in an unequivocal way. Currently, there are various riskassessment methodologies (RAMs) and the question has risen to what extent these RAMsyield similar outcome and, if not, whether the outcome can be harmonized, i.e. whether theresults of the various RAMs can be made compatible or comparable. In this study i) the currentstatus of RAMs for erosion, soil organic matter decline, compaction, salinization and landslidesin Europe (EU27) is reviewed, and ii) the need and the options for harmonization are assessed.The ¿need for harmonization¿ was defined as the likelihood of achieving different outcomeswhen using different RAMs, whereas the options for harmonization refer to the efforts that arerequired to harmonize soil RAMs. The current status of RAMSs in EU-27 was assessed on thebasis of questionnaires, which were sent out to soil specialists and policy officers in all MemberStates. We received more than 100 (response rate >50%) completed questionnaires. It turnedout that many of the so called RAMs are still incomplete; they are ¿process (or threat)quantifications¿ rather than methodologies that assess the risk of a soil threat. Moreover, therewere significant differences between RAMs for a soil threat in terms of (i) the notion of thethreat, (ii) data collection, (iii) data processing, (iv) data interpretation, and (v) risk perception.The need for harmonization appeared highest for erosion and salinization, whereas the optionsfor harmonization were best for SOM decline and landslides. Harmonization of soil RAMs maybe very complex and for that reason not always feasible. We suggest two options that mayfacilitate unequivocal identification of risk (or priority) areas for soil threats, i) a two Tieredapproach based on data availability and spatial scale and ii) generic harmonization, i.e.combining standardization and harmonization in a rather pragmatic way.