Vegetation cover data from line-intercept transects in the long-term Small Mammal Exclusion Study (SMES) at Jornada Basin LTER, 1995-2005

This package contains perennial vegetation cover data measured using
the line-intercept method from plots with various levels of herbivore
exclusion on Jornada Experimental Range (JER) and Chihuahuan Desert
Rangeland Research Center (CDRRC) lands. Study sites were established
in 1995; one in black grama grassland and the other in creosotebush
shrubland to compare the impact of herbivores on ecosystem processes
between these vegetation types. Parallel studies were established at
the Sevilleta LTER site (New Mexico, USA) and Mapimi Biosphere Reserve
(Durango, Mexico). Each study site is 1 km by 0.5 km in area. Four
replicate experimental blocks were randomly located at the grassland
study site to measure vegetation responses using exclusion treatments
including a) all mammalian herbivores, including cattle, lagomorphs,
and rodents, b) lagomorphs and cattle only, c) cattle only, and d)
control accessible to all herbivores. Because grazing cattle are
excluded from the entire creosote site, only three replicate
experimental blocks were randomly located there including a) all
mammalian herbivores, including lagomorphs, and rodents, b) lagomorphs
only, and c) control accessible to all herbivores. Thirty-six sampling
points were positioned at 5.8-meter intervals on a systematically
located 6 by 6 point grid within each plot. A permanent one-meter by
one-meter vegetation measurement quadrat is located at each of the 36
points. The vegetation line-intercept measurements in this data
package were made in fall 1995 and fall 2005 to coincide with
low-level aerial photography campaigns. Three 29-meter lines were
measured along three out of six rows of permanent vegetation quadrats.
Intercept locations for live, perennial plant cover and bare ground
were measured along each line at 10cm resolution, which is comparable
to the resolution of the aerial photos. Plants were identified to
species level where possible. The resulting cover data can used to
ground-truth cover estimates from aerial photography or for comparison
to annual measures of vegetation from 1 x 1 meter permanent vegetation
quadrats. This study is complete.