Lane Mountain Milk-Vetch - Species Distribution Model, DRECP

These data are statistical model outputs for Lane Mountain milk-vetch (Astragalus jaegerianus ) 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 as a union of USDA ecoregion subsections with occurrences and 10km buffer of occurrences, at 270 m resolution with 211 detections points obtained 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 ten 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) in order of importance:

Precipitation of warmest quarter (mm);
Soil water content at wilting point, produced by A. & L. Flint;
Minimum temperature of coldest period (°C, x10);
Annual precipitation (mm);
Soil porosity, produced by A. and L. Flint;
Soil thickness, produced by A. &. L. Flint;
Soil pH (pH scale) from 0-50cm, derived from SSURGO or STATSGO where SSURGO was unavailable.  The mapunit area weighted average of the soil component percent area weighted average of the soil component horizon depth weighted average of ph1to1h2o_r in table chorizon;
Topographic relief in the 270m cell estimated as the standard deviation of elevations from 30m digital elevation model;
Integrated solar radiation (WH/m2, ESRI Spatial Analyst Area Solar Radiation).  Derived from the interior of 30m NED DEM tiles buffered to 300m.  Integrated from 2012-02-29 to 2012-05-30.  Average integrated value in each 270m pixel;
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.