ERP Related Publications Abstracts
A gap analysis
Frank W. Davis
and David M. Stoms
assesses the distribution of plant community types and vertebrate
species distributions among land classes defined by ownership and
levels of protection of biodiversity. Gap analysis helps to identify
which plant communities and species might be especially vulnerable
to different human activities that can lead to habitat conversion
presents a gap analysis of plant community types the Sierra Nevada
region, an area of 63,111 km2 (24,368 mi2).
Ownership of the region is 37% private, 47% national forests, 10%
national parks, 5% Bureau of Land Management, and less than 2% in
other public lands. Land ownership and land management patterns
contrast sharply between the northern Sierra Nevada versus the central
and southern subregions. Parks and reserve lands contribute less
than 2% of the northern region versus 27% of the central/southern.
We mapped eighty-eight
natural plant community types within the region. Sixty-seven types
were mapped over areas greater than 25 km2 (9.65 mi2.
The ownership profiles of Sierran plant communities systematically
reflect the concentration of private lands at lower elevations and
of national parks in the central and southern portion of the range.
Less than 1% of the foothill woodland zone of the Sierra Nevada
is in designated reserves or other areas managed primarily for native
biodiversity, and over 95% of the distribution of most foothill
community types is available for grazing. Low to middle elevation
Sierran forests are not well represented in designated reserves,
especially in the northern Sierra Nevada. However, large areas of
most of these forest types on U.S. Forest Service lands have been
administratively withdrawn from intensive timber management based
on current forest plans. Many high-elevation forest and shrubland
community types are well represented in parks and ungrazed wilderness
areas. Our analysis identifies thirty-two widespread community types
whose conservation status warrants concern and twelve types that
appear well protected based on their present distributions.