These data are statistical model outputs for Owens Valley
checkerbloom (
Sidalcea covillei
) 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 73 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 9 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:
Temperature seasonality (C of V,
x100);
Soil water content at wilting
point, 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;
Maximum temperature of warmest period
(°C, x10);
Soil porosity, produced by A. and
L. Flint;
Soil thickness, produced by A.
&. L. Flint;
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).
This model has a 10-fold cross validated AUC score of 0.904
(standard deviation 0.041).
The binary layer depicting predicted suitable habitat was
derived using the maximum training sensitivity and specificity threshold (0.257).