This collection contains files related to calculating voyage-related marine biosecurity risk from computer-generated maritime vessel paths between pairs of Marine Ecoregions Of the World (MEOW) ecoprovinces (Spalding et al. 2007). The physical length of the path is used to calculate voyage duration risk. The cross-latitudinal extent of the path is used to calculate voyage path risk. A list of files included in the collection follows. 

A) VoyRisk_input-data.zip:
1. EcoProvinceCentroids_WGS84.* (8-part shapefile: extensions are cpg, dbf, prj, sbn, sbx, shp, shp.xml, shx)
2. WorldOceans_Canals_fixed.* (8-part shapefile: extensions are cpg, dbf, prj, sbn, sbx, shp, shp.xml, shx)
3. WorldOceans_fixed_raster_005res.tif
4. tr1_.RData
5. tr1C.RData
6. ecoprovDistanceTable.csv
7. VoyRisk_input-data_metadata-fc.xml

B) VoyRisk_distance_analysis_code.zip
1. VoyRisk_trade_connections_script.R
2. VoyRisk_localFunctions.R
3. VoyRisk_distance_analysis_code_metadata.PDF 

C) VoyRisk_interim-data.zip:
1. VoyRisk_ecoprovs_distances_MinMaxLat.csv
2. VoyRisk_interim-data_metadata-main.xml
3. VoyRisk_interim-data_metadata-fc.xml

D) EcoprovPair_riskcalc_code.zip
1. VoyRisk_physdist_pair_ecoprov.R
2. EnvSim_envdist_pair_ecoprov.R
3. VoyRisk_physdist_pair_ecoprov_metadata.PDF
4. EnvSim_envdist_pair_ecoprov_metadata.PDF

E) EcoprovPair_final-data.zip:
1. ENVDIST_ECOPROV.csv
2. VoyRisk_physdist.csv
3. VoyRisk_crosslatdist.csv
4. ecoprov_envdist_scaled.csv
5. ecoprov_physdist_scaled.csv
6. ecoprov_crosslat_scaled.csv
7. ecoprov_pair_risk_matrices.RData
8. EcoprovPair_final-data_metadata.xml
9. EcoprovPair_final-data_Example.pdf

F) EcoprovPair_README.txt (this file)

VOYRISK_input-data.zip (A) contains the input data files for the R script VoyRisk_trade_connections_script.R (B.1), which uses functions located in VoyRisk_localFunctions.R (B.2) to create the paths between each pair of ecoprovinces, then derive path length and the minimum and maximum latitude of each path. The output file, VoyRisk_ecoprovs_distances_MinMaxLat.csv (C.1), is the input file for VoyRisk_physdist_pair_ecoprov.R (D.1), which calculates risk values from the voyage-related distance values with the general formula:

risk = 1-(distance/ceiling(max(distance)))

In addition, the R script EnvSim_envdist_pair_ecoprov.R (D.2) is modified from the R script EnvironmentalDistanceCalculations.R (Tzeng 2022, doi: 10.17608/k6.auckland.15184107) to calculate environmental distances between ecoprovince pair members based on temperature and salinity (Tzeng 2022, doi: 10.17608/k6.auckland.15184095), followed by environmental similarity risk using the above general formula. 

The final dataset (E) consists of six matrices that each contain one of the following variables associated with each possible pair of MEOW ecoprovinces: environmental distance (E.1), physical distance in meters (E.2), cross-latitude distance in decimal degrees (E.3), environmental similarity risk (E.4), voyage duration risk (E.5), and voyage path risk (E.6). For each matrix, the 62 ecoprovinces are listed in the same order in both rows and columns. Values for each pair of ecoprovinces can be found at the intersection of row and column for each pairwise combination.

The file ecoprov_pair_risk_matrices.RData (E.7) is an R workspace that contains the final data for path lengths ("geographic distance"), cross-latitude extent, voyage duration risk, and voyage path risk. The variable EnvSim contains the environmental distances between ecoprovince pair members (from Tzeng 2022, doi: 10.17608/k6.auckland.15184095), and environmental similarity risk. The metadata file EcoprovPair_final-data_metadata.xml (E.8) describes the data matrices in the ISO 19115 metadata standard, and EcoprovPair_final-data_Example.pdf has an example of the data format.

This README file, EcoprovPair_README.txt (F), was written by M.W. Tzeng and last modified on 30 November 2022.

References:

Spalding, M.D., Fox, H.E., Allen, G.R., Davidson, N., Ferdaña, Z.A., Finlayson, M., Halpern, B.S., Jorge, M.A., Lombana, A., Lourie, S.A., Martin, K.D., McManus, E., Molnar, J., Recchia, C.A., and Robertson, J. (2007). Marine Ecoregions of the World: a bioregionalization of coast and shelf areas. BioScience 57: 573-583. DOI: http://dx.doi.org/10.1641/B570707 

Tzeng, M.W. (2022). Environmental Distances Between Marine Ecosystems of the World (MEOW) Ecoregions and Ecoprovinces. Frontiers in Marine Science 9: 764771. DOI: http://dx.doi.org/10.3389/fmars.2022.764771