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Title: Historical context and ecological impact of the 1950s drought in the American Southwest

Conference · · Bulletin of the Ecological Society of America; (United States)
OSTI ID:6146272
;  [1]
  1. Geological Survey, Tucson, AZ (United States)

In the American Southwest, the 1950s drought caused massive vegetation dieoffs from the lowland deserts well into conifer woodlands of the uplands, resetting demographic clocks and creating disequilibria in carbon and nutrient cycling. Climate reconstructions from tree rings indicate up to 500-year return periods for droughts of similar magnitude. Broadscale mortality of long-lived conifers yielded >100 m elevational shifts in ecotonal boundaries that had been stable for at least 2500 years, according to a high-resolution packrat midden record. The drought also may have accelerated recent invasion of shurblands into grasslands, and the northward and upward expansion of xerophytes such as Larrea tridentata. Long-term monitoring efforts in the Southwest, particularly those contemplated or initiated only recently (e.g., 1988 on the Sevilleta LTER, New Mexico), should consider the imprint of the 1950s drought on present and future vegetation dynamics.

OSTI ID:
6146272
Report Number(s):
CONF-930798-; CODEN: BECLAG
Journal Information:
Bulletin of the Ecological Society of America; (United States), Vol. 74:2; Conference: 78. annual Ecological Society of America (ESA) meeting, Madison, WI (United States), 31 Jul - 4 Aug 1993; ISSN 0012-9623
Country of Publication:
United States
Language:
English