Vegetation of semi-stable rangeland dunes of the Navajo Nation, Southwestern USA

Arid Land Research and Management
By:  and 

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Abstract

Dune destabilization and increased mobility is a worldwide issue causing ecological, economic, and health problems for the inhabitants of areas with extensive dune fields. Dunes cover nearly a third of the Navajo Nation within the Colorado Plateau of southwestern USA. There, higher temperatures and prolonged drought beginning in 1996 have produced significant increases in dune mobility. Vegetation plays an important role in dune stabilization, but there are few studies of the plants of the aeolian surfaces of this region. We examined plant species and their attributes within a moderately vegetated dune field of the Navajo Nation to understand the types and characteristics of plants that stabilize rangeland dunes. These dunes supported a low cover of mixed grass-scrubland with fifty-two perennial and annual species including extensive occurrence of non-native annual Salsola spp. Perennial grass richness and shrub cover were positively associated with increased soil sand composition. Taprooted shrubs were more common on sandier substrates. Most dominant grasses had C4 photosynthesis, suggestive of higher water-use efficiencies and growth advantage in warm arid environments. Plant cover was commonly below the threshold of dune stabilization. Increasing sand movement with continued aridity will select for plants adapted to burial, deflation, and abrasion. The study indicates plants tolerant of increased sand mobility and burial but more investigation is needed to identify the plants adapted to establish and regenerate under these conditions. In addition, the role of Salsola spp. in promoting decline of perennial grasses and shrubs needs clarification.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Vegetation of semi-stable rangeland dunes of the Navajo Nation, Southwestern USA
Series title Arid Land Research and Management
DOI 10.1080/15324982.2016.1138157
Volume 30
Issue 4
Year Published 2016
Language English
Publisher Taylor and Francis
Contributing office(s) Southwest Biological Science Center
Description 12 p.
First page 400
Last page 411
Country United States
State Arizona, Colorado, New Mexico, Utah
Other Geospatial Navajo Nation
Online Only (Y/N) N
Additional Online Files (Y/N) N