Document: DIA-3-40-34

An ecological description and comparison of the Chihuahuan Desert upland communities of the Diamond Y Springs Preserve of west Texas.

HART, A.D.* and O.W.VAN AUKEN

The University of Texas at San Antonio, San Antonio, TX 78249 USA ¹

Abstract:
Part of the Diamond Y Springs Preserve in Pecos county, Texas is a salt marsh located in the eastern part of the Chihuahuan desert. The drainage area of the spring supports several threatened and endangered species including Helianthus paradoxus (puzzle sunflower). Undescribed upland communities of woody plants exist on an apparent elevational gradient bordering the marsh. The quadrat method was used to describe these upland communities in terms of their total densities, individual species densities, canopy areas and frequencies. Soil samples were collected from each community examined. Soil depth, water content, water holding capacity, particle size, salinity and major anions and cations were also measured. There appear to be at least two distinct upland communities. Prosopis glandulosa (honey mesquite) communities were found on relatively deep soil. Chihuahuan desert shrub communities were found on shallower soil. In addition a series of transect lines were established from the marsh to the highest elevations. Using the line point method, the woody and herbaceous plants were identified along these transects. Elevation, distance from the marsh, soil depth and other soil factors were also measured along these transects. GIS and ordination techniques were used in the analysis of the relationships between these communities and various abiotic factors.

Keywords: Chihuahuan Desert

This abstract is being presented at: 3:30 PM in session:
Poster Session #17: Vegetative Analysis.