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Biological data: georeferencing. Monica Pape ş University of Kansas pmonica@ku.edu. Sources of occurrence data. Natural history museum collections (many in distributed databases) – contains the bulk of species’ distribution information Literature citations (monographs, papers, etc) Surveys.
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Biological data: georeferencing Monica Papeş University of Kansas pmonica@ku.edu
Sources of occurrence data • Natural history museum collections (many in distributed databases) – contains the bulk of species’ distribution information • Literature citations (monographs, papers, etc) • Surveys
Potential issues with NHM occurrence data • Taxonomy: unidentified or wrong identifications; outdated taxonomy • Sample bias • Locality description too vague, misspelled, unreadable handwriting, etc. • Faulty georeferencing
What is georeferencing?(simple response) USA, Georgia, Augusta, Wheeless Rd., 0.5 mi S of Gordon Hwy locality georeferenced to Latitude: 33.444642 Longitude:-82.045296 • Assigning geographic coordinates to a locality description
Where to find coordinates? 1. Gazetteers - Paper based - Online databases
Where to find coordinates of localities? 1. Gazetteers - Paper based - Online databases GeoNet Names Server – worldwide coverage, no maps http://gnswww.nga.mil/geonames/GNS/index.jsp
GeoNet Names Server – worldwide coverage, no maps http://gnswww.nga.mil/geonames/GNS/index.jsp
Another example of online databases: Alexandria Digital Library – worldwide coverage, with maps http://middleware.alexandria.ucsb.edu/client/gaz/adl/index.jsp
Where to find coordinates of localities 1. Gazetteers - Paper based - Online databases 2. Maps - Paper based - Electronic (digitized) *Exhaustive list of sources can be found on HerpNet website: http://www.herpnet.org/Gazetteer/GeorefResources.htm
Georeferencing… more in depth look • e.g.1: Lawrence • e.g.2: Lawrence, Douglas Co, Kansas, USA • e.g.3: 5 km E of Lawrence, DG, KS, USA • e.g.4: 5 km SE of Lawrence, DG, KS, USA • …
More in depth look… issues • Assumptions: localities are accurate and complete • Locality string has to be interpreted e.g. USA, KS, Dickinson Co, Jct I-70 & KS Hwy 15 in Abilene, 1 mi S, 3.5 mi W • There are inherent uncertainties with each locality description (even with GPS coordinates!)
Causes of uncertainty: • The extent of the locality – can be estimated using: • →bounding box method • →point-radius method • -... in future: shape method: complex, • complete representation • Imprecision in distance or direction measurements; map scale; unknown datum; GPS accuracy
Thus… we need to calculate a “confidence interval” for georeferencing done. Luckily, there is a CALCULATOR for this purpose! http://manisnet.org/gci2.html
Automated, batch processing tools (The future looks bright!) GEOLocate – georeferencing without error estimates designed for North America; recently expanded to include the whole world • http://www.museum.tulane.edu/geolocate/default.aspx BioGeomancer – georeferencing with error estimates Still in the developing stage, but improving fast • http://www.biogeomancer.org/
Everything there is to know about georeferencing: Guide to Best Practices for Georeferencing Edited by Arthur D. Chapman and John Wieczorek (2006) Available for download: http://www.gbif.org/prog/digit/Georeferencing
Vague Biologically unlikely Very bad localities…. REAL LOCALITIES FROM MaNIS project Non-sensical Requires specific knowledge T-shirt: http://herpnet.org/gbif/tshirt.html