Cushenbury buckwheat - Species Distribution Model, DRECP

These data are statistical model outputs for Cushenbury buckwheat (Eriogonum ovalifolium var. vineum ) species distribution, completed by CBI. Predictions of habitat occupancy were generated from Maxent models for the DRECP.

This species distribution model was produced for a limited extent within the DRECP region, defined by the Carbonate Habitat Management Area extent (Todd G. Olson, Carbonate Habitat Management Strategy, 2003, http://www.dmg.gov/documents/WMP_Volumes/Appendix%20S%20-%20CHMS.pdf), at 270 m resolution with 194 detections points obtained in March 2013 from CNDDB (California Department of Fish and Wildlife, Biogeographic Data Branch) and Consortium of California Herbaria (http://ucjeps.berkeley.edu/consortium/).

The model was built with the following eight environmental predictors (provided to CBI by Frank Davis’ Biogeography Lab at UC Santa Barbara, created for the CA Energy Commission’s project “Cumulative Biological Impacts Framework for Solar Energy in the CA Desert”, 500-10-021; except for the carbonate habitat types, which was provided to CBI by Dudek) in order of importance:

Carbonate habitat types (for description, see http://www.dmg.gov/documents/WMP_Volumes/Appendix%20S%20-%20CHMS.pdf), categorical presence/absence, indicating the presence of critical, suitable, and occupied carbonate plant habitat types, each 270m pixel.  
Maximum temperature of warmest period (°C, x10);
Soil available water storage (cm) from 0-50cm, derived from SSURGO or STATSGO where SSURGO was unavailable.  The mapunit-area-weighted average of aws050wta in table muaggatt;
Soil water content at wilting point, produced by A. & L. Flint;
Soil thickness, produced by A. &. L. Flint;
Topographic relief in the 270m cell estimated as the standard deviation of  elevations from 30m digital elevation model;
Flow accumulation (ESRI Spatial Analyst Flow Accumulation), calculated from 90m HydroSHEDS flow direction rasters.  90m model data were log(x+1) transformed.  Maximum of the transformed values in each 270m pixel;
Precipitation of warmest quarter (mm)