Alien plant presence dataset from the point-radius plot surveys in 2010-2015 in Taiwan

Study Extent

The study area covered whole Taiwan island.

Sampling

We made sample plots with radius in 20 meters along road network covered Taiwan and documented the presence of alien plants in each plot.

Quality Control

1) Geo-referencing sampling points: We georeferenced the center of each sampling plot by using a Garmin 60CX GPS receiver and documented the coordinate in decimal degrees of latitude and longitude with accuracy to 0.00001 as well as the altitude with accuracy to 1 meter. We documented the coordinates only when GPS signal was fixed and the error of horizontal positioning was within 5 meters. 2) Cleaning scientific names: The scientific names of all plants in the dataset were matched and corrected based on the taxonomic data from the GBIF backbone taxonomy and the Catalog of Life by using the scientific name matching service developed by Taiwan Biodiversity Information Facility (http://match.taibif.tw/). We adopted the accepted name as well as retrieved the name of higher taxonomic rank and the taxon rank identified for each input name. 3) Standardizing data structure: We adopted the terms from the vocabularies of Darwin Core Sampling-event and the extensions of MeasureOrFacts and Occurrence Core to transform the original data structure fitted into Darwin Core star-schema for better integration into GBIF global data repository.

Method steps

1. Field sampling: Sampling points were selected along road network covering Taiwan. Distance between two adjacent points along a road was within 2.0-2.5 kilometers. Sampling points were georeferenced by using a Garmin 60CX GPS receiver.
2. Compiling the field records: We used Microsoft Excel to create a workbook file with two worksheets to input the data of sampling plots and the presence of plants in each plot. The plot worksheet included the fields of sampling date, plot identifier, habitat, latitude, longitude, altitude, and county to document the detailed information of each plot. The presence worksheet included fields of sampling date, plot identifier, plant identifier, scientific names, and vernacular names in Chinese to document the presence information of plants in each plot.
3. Cleaning scientific names and retrieve relevant taxonomic information: For correcting any error in spelling scientific names, adopting accepted or valid scientific names, and getting complete information on the hierarchy of taxon ranks, we check all input names against the GBIF backbone taxonomy embedded in the name matching service (http://match.taibif.tw/) developed by Taiwan Biodiversity Information Facility in a first batch and save the matching results in a CSV text file. Then, we used Notepad++, a free text editor to open this file. All matching results were copied into the occurrence worksheet aligned with the input names to check the quality of input names by using the score field from the matching results as a filter. Some names could not be found in GBIF backbone taxonomy (scored as N/A) then we matched these names against the taxonomic data from Catalog of Life embedded the TaiBIF name matching service as a send batch in the same way to check the quality and to correct the errors in these names. Finally, we got a cleaned and accepted scientific names with complete name information on the hierarchy of taxonomic ranks for each occurrence record.
4. Standardizing data structure: For better preservation of complete information of the dataset and better integration into the GBIF global data portal, we adopted the Darwin Core star-schema and transformed our original two data tables (plot and occurrence of plant in plot) into three tables (Event, MeasurementOrFacts, and Occurrence) by using the Darwin Core terms defined for describing sampling events, measurements conducted in the sampling events and the occurrence records from each sampling event. All three data files were saved as UTF-8 chracter encoded CSV file. Users can open these files by any free text editor, such Notepad ++ or PSPad then select and copy the content into a spreadsheet software, such as the Clibre Office Calc or Microsoft Office Excel, for further editing and reuse.

Vascular plants (Magnoliophyta, Pteridophyta)

1. Magnoliophyta
   common name: angiosperms rank: phylum
2. Pteridophyta
   common name: cryptogams rank: phylum

Taiwan