Vibrisses: anomaly detection thresholds for different trace elements (RMQS)
This dataset gathers the results of the calculation of indicators that can serve as detection thresholds for trace element anomalies (arsenic, cadmium, cobalt, chromium, copper, mercury, nickel, lead, thallium, zinc) in surface soils . These indicators correspond to vibrisses calculated from a set of measurements located within a radius of 50 km around the considered point. The measurements correspond to total contents of trace elements and come from the sites of the Network of Measurements for horizons 0-30 cm (all elements) and 30-50 cm (except for arsenic and Mercury).
We consider here that these regionalized calculations of the vibrisses play a role of indicator of regional tendency taking into account both the values of pedo-geochemical bottoms and the contributions of anthropic origin. They correspond to the limit content beyond which a value can be considered as anomalous. They thus make it possible to detect punctual anomalies while avoiding the local background value.
Simple
- Date (Creation)
- 2018-01-06
- Date (Publication)
- 2018-01-06
- Date (Revision)
- 2023-02-13
- Citation identifier
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https://agroenvgeo.data.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/63e6c177-455e-5805-b70b-0894ee1c7174
- Presentation form
- Digital map
- Credit
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Saby, Nicolas; Villanneau, E; Toutain, B; Arrouays, D., 2018, "Seuils de détection d’anomalies pour 8 éléments traces métalliques (RMQS)", https://doi.org/10.15454/UEZXBY, Portail Data Inra, V 1
- Status
- Completed
- Point of contact
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Organisation name Individual name Electronic mail address Role INRAE Info&Sols
Custodian
- Maintenance and update frequency
- Not planned
- Resource format
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Name Version postgis
- Keywords
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RMQS
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Contamination
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data processing
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vibrisses
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France
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éléments traces
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statistiques
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ETM
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Resource specific usage
- Use limitation
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The values provided on the anomaly detection thresholds must be handled with care. The interpretations that are made must take into account the rather frustrating nature of these indicators. Indeed, it is important to note that the calculations do not take into account local soil processes.
- Use limitation
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Data subject to open license CC0 – « Public Domain Dedication ».
- Use limitation
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Free use, subject to mentioning the source
(at least the name of the producer) and the date of its last update.
- Access constraints
- Other restrictions
- Use constraints
- License
- Other constraints
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No restriction of public access
- Spatial representation type
- Vector
- Denominator
- 16000
- Language
- Français
- Topic category
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- Geoscientific information
- Environment
- Description
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France
- Reference system identifier
- http://www.opengis.net/def / EPSG:2154 /
- Topology level
- Geometry only
- Geometric object type
- Surface
- Geometric object count
- 2295
- Distribution format
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Name Version postgis
- Distributor contact
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Organisation name Individual name Electronic mail address Role INRAE Info&Sols
Distributor
- OnLine resource
- Hierarchy level
- Dataset
- Statement
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Most of the steps for the calculation of the vibrisses are realized using scripts executed in the R software (R Development Core Team, 2007).
The first step consists in calculating the distance between sites. Then, the trace elements concentrations are extracted from the database.
The following steps are realized for each trace element and each layer with only one R script:
• Selection, for each site, of the trace elements concentrations from the neighbouring sites within a distance of 50 km,
• Count the number of sites with a trace element concentration, the vibrisse calculation is done only of there are at least 10 sites,
• Calculation, for each site, of the vibrisse with the following formula: v = median + 3x interquartile range.
Source: E. Villanneau, C. Perry-Giraud, N. Saby, C. Jolivet, F. Marot, D. Maton, A. Floch-Barneaud, V. Antoni et D. Arrouays, 2008. Détection de valeurs anomaliques d’éléments traces métalliques dans les sols à l’aide du Réseau de Mesure de la Qualité des Sols. Étude et Gestion des Sols, Volume 15,3, 2008 - pages 183 à 200
Metadata
- File identifier
- 63e6c177-455e-5805-b70b-0894ee1c7174 XML
- Metadata language
- Français
- Character set
- UTF8
- Hierarchy level
- Dataset
- Date stamp
- 2024-02-06T15:21:23
- Metadata standard name
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ISO 19115:2003/19139
- Metadata standard version
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1.0
- Metadata author
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Organisation name Individual name Electronic mail address Role INRAE Info&Sols
Point of contact
- Other language
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Language Character encoding English French UTF8