Leaf litter cover data on 1m x 1m plots from the long-term Small Mammal Exclusion Study (SMES) at Jornada Basin LTER, 1995-2020

This data package contains leaf litter cover data from plots with
various levels of herbivore exclusion on the Jornada Experimental
Range. 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. Each year in spring and fall from
1995-2005, the total percent cover of leaf litter in each quadrat
was estimated by summing the percent of each 10 cm square within a
quadrat (including 100 10-cm squares) containing leaf litter (See
methods for a detailed explanation). After 2005, sampling frequency
changed to every 5 years. This study is ongoing.