Background

There are four major biomes that converge in New Mexico: Colorado Plateau Shrub Steppe, Chihuahuan Desert, Great Plains Grassland, and Conifer Woodland (Figure 1). Each biome may contain multiple vegetation types (plant communities), and thus several vegetation types can coexist over very small spatial scales. The vegetation present in a given area at a given point in time is the result of an interaction between abiotic environmental drivers and certain biotic factors. Environmental factors that influence vegetation include temperature, precipitation, elevation, and soil type, while biotic factors may include physiological tolerances of individuals and species and plant interactions (competition, predation, mutualism, facilitation, etc.).

In the Chihuahuan Desert , there are two main vegetation types: black grama grassland (Figure 2) and creosote shrubland (Figure 3.). Although these two species can coexist, once creosote establishes in black grama grassland it is often able to out-compete black grama and mutually exclude it. This results in a shift from grassland to shrubland, and is associated with a decrease in plant species diversity, increased erosion, lower forage quality for herbivores, and altered biogeochemical cycles.

Objective

The purpose of this study was to look at the relationship between vegetation type (i.e., Creosote Shrubland and Black Grama Grassland) and environmental variables (i.e., temperature, precipitation, elevation, and soil type). The results of this study could have implications for predicting future patterns of vegetation change.