Geocoding van de Nederlandse botanische collectie van Naturalis met hulp van citizen scientists en crowdsourcing

The botanical collection of Naturalis Biodiversity Center contains about 550,000 specimens from The Netherlands. All specimens have been scanned and transcribed. However, reliable geographical coordinates were present in only 8,600 cases. Aim of this project is to enlarge this number by means of (1) extraction of grid square codes and coordinate pairs from text fields, (2) semi-automated and (3) manual geocoding based on location names using crowd sourcing by FLORON volunteers. We only took specimens into account with taxon names and collector names that could by mapped to taxon and people present in the National Database Flora and Fauna, about 230,000 specimens. By the end of the first year of the project, a precise location (less than 1000 m inaccuracy) had been assigned to 28,000 records. A tentative location at 2500 m inaccuracy has been assigned to the other 202,000 records.