Continental interior storm tracks, tritium deposition, and precipitation isotopes at the Great Basin-Rocky Mountain physiographic provinces transition zone, USA

We provide a preliminary nomenclatural proposal and a digital map of the Nearctic region, based on published regionalizations, especially Dice (1943), and applying the International Code of Area Nomenclature. The Nearctic region is comprised of three subregions (one of them with two dominions), one transition zone and 29 provinces. The Arctic subregion, in northern North America and Greenland, includes the Eskimoan, Hudsonian, Aleutian and Sitkan provinces. The Western subregion, in western North America, includes the Californian dominion, with the Californian and Oregonian provinces; and the Rocky Mountain dominion, including the Montanian, Saskatchewan, Palusian, Artemisian, Coloradan, Kansan, Mohavian, Navahonian, Sonoran, Chihuahuan, Comanche, and Baja California provinces. The Alleghany subregion, in eastern North America, includes the Illinoian, Canadian, Carolinian, Texan, Austroriparian, and Tamaulipan provinces. The Mexican Transition Zone, situated in the area of overlap with the Neotropical region, includes the Sierra Madre Occidental, Sierra Madre Oriental, Transmexican Volcanic Belt, Sierra Madre del Sur and Chiapas Highlands provinces.

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Erosion Potential of a Burn Site in the Mojave-Great Basin Transition Zone: Interim Summary of One Year of Measurements

10.2172/1010273 ◽

2010 ◽

Author(s):

V. Etyemezian ◽

D. Shafer ◽

J. Miller ◽

I. Kavouras ◽

S. Campbell ◽

...

Keyword(s):

Transition Zone ◽

Great Basin ◽

One Year

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Two New Late Pleistocene Avifaunas From New Mexico

The Condor ◽

10.1093/condor/108.3.721 ◽

2006 ◽

Vol 108 (3) ◽

pp. 721-730 ◽

Cited By ~ 1

Author(s):

Rebecka L. Brasso ◽

Steven D. Emslie

Keyword(s):

New Mexico ◽

Great Basin ◽

Late Pleistocene ◽

New Records ◽

Rocky Mountain ◽

Subalpine Forest ◽

Radiocarbon Dates ◽

Aegolius Funereus ◽

Boreal Owl ◽

Gymnogyps Californianus

Abstract We report two new late Pleistocene avifaunas from New Mexico, recovered from Sandia Cave during archaeological excavations by F. Hibben in the 1930s and the nearby Marmot Cave excavated in 2000. The fossil assemblage from Sandia Cave consists of at least 30 taxa, including seven extralimital and two extinct species, Coragyps occidentalis (extinct vulture) and Ectopistes migratorius (Passenger Pigeon). The avifauna from Marmot Cave is limited to eight taxa shared with Sandia Cave. Two new records of Gymnogyps californianus (California Condor) are reported from these sites, as well as new records of Lagopus sp. (ptarmigan), Aegolius funereus (Boreal Owl), and Micrathene whitneyi (Elf Owl) from New Mexico. Two new radiocarbon dates on fossil G. californianus from Sandia and Marmot cave are reported at 10 795 ± 50 and 25 090 ± 220 14C years before present (B.P.), respectively. These collections provide further evidence for mixed avian communities in New Mexico during the late Pleistocene and are similar to other cave avifaunas of comparable age from the Great Basin and Rocky Mountain regions. The birds from Sandia Cave that are shared with other fossil avifaunas include species currently found in arctic tundra, boreal, and steppe habitats, as well as open, xeric communities. This collection provides additional evidence for widespread steppe-tundra, shrub, and subalpine forest environments at lower elevations of western North America during the late Pleistocene.

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Western Margin of the Rocky Mountain Geosyncline in the Great Basin: ABSTRACT

AAPG Bulletin ◽

10.1306/5ceade0c-16bb-11d7-8645000102c1865d ◽

1953 ◽

Vol 37 ◽

Author(s):

Wm. Lee Stokes

Keyword(s):

Great Basin ◽

Rocky Mountain ◽

Western Margin

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Holocene Vegetation and Climate History of the Northern Bighorn Basin, Southern Montana

Quaternary Research ◽

10.1006/qres.2002.2342 ◽

2002 ◽

Vol 58 (2) ◽

pp. 171-181 ◽

Cited By ~ 24

Author(s):

Mark E. Lyford ◽

Julio L. Betancourt ◽

Stephen T. Jackson

Keyword(s):

Climate Change ◽

Great Basin ◽

Rocky Mountain ◽

Bighorn Basin ◽

Downward Movement ◽

Climate History ◽

Juniperus Osteosperma ◽

Rocky Mountain Region ◽

History Of ◽

Vegetation And Climate

AbstractRecords of Holocene vegetation and climate change at low elevations (<2000 m) are rare in the central Rocky Mountain region. We developed a record of Holocene vegetation and climate change from 55 14C-dated woodrat middens at two low-elevation sites (1275 to 1590 m), currently vegetated by Juniperus osteosperma woodlands, in the northern Bighorn Basin. Macrofossil and pollen analyses show that the early Holocene was cooler than today, with warming and drying in the middle Holocene. During the Holocene, boreal (Juniperus communis, J. horizontalis) and montane species (J. scopulorum) were replaced by a Great Basin species (J. osteosperma). J. osteosperma colonized the east side of the Pryor Mountains 4700 14C yr B.P. Downward movement of lower treeline indicates wetter conditions between 4400 and 2700 14C yr B.P. Increased aridity after 2700 14C yr B.P. initiated expansion of J. osteosperma from the east to west side of the Pryor Mountains.

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Diversity of Washoe pine and comparisons with allozymes of ponderosa pine races

Canadian Journal of Forest Research ◽

10.1139/x90-044 ◽

1990 ◽

Vol 20 (3) ◽

pp. 298-308 ◽

Cited By ~ 30

Author(s):

Charles R. Niebling ◽

M. Thompson Conkle

Keyword(s):

Genetic Distance ◽

Great Basin ◽

Ponderosa Pine ◽

Rocky Mountain ◽

Electrophoretic Analysis ◽

Allozyme Variation ◽

Genetic Distances ◽

Isolated Populations ◽

The North ◽

The Pacific

Washoe pine (Pinuswashoensis Mason and Stockwell), a narrow endemic native to mountains on the western rim of the Great Basin in northeastern California and northwestern Nevada, may be on the verge of extinction. Lowered genetic diversity and increased interpopulation differentiation are expected evolutionary consequences for small, isolated populations like those of Washoe pine. But the species has levels of allozyme variation (estimated average heterozygosity for 26 loci equals 0.148) similar to those for widespread geographic races of ponderosa pine (Pinusponderosa Laws.), which are likely to be its closest extant relatives. Heterozygosity in ponderosa pine was 0.144 in the Pacific race, 0.178 in the North Plateau race, and 0.164 in the Rocky Mountain race. Electrophoretic analysis of trees in the three well-documented populations of Washoe pine revealed only minor and nonsignificant population to population differentiation (98.4% of allozyme variation was among samples within populations). Pair-wise genetic distances between the Washoe populations and the three northern races of ponderosa pine indicated that its closest similarity was with the North Plateau race (Nei's unbiased genetic distance averaged 0.004); the next closest similarity was with samples of the Pacific race (genetic distance 0.013). Washoe pine and the Pacific and North Plateau races of ponderosa pine were all strongly differentiated from the Rocky Mountain race of ponderosa pine (genetic distances were 0.066, 0.082, and 0.060, respectively. The few remaining populations of Washoe pine may be a potentially valuable gene source for the yellow pines of North America.

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