Riparian plant succession in the dam-regulated Colorado River: Why is saltcedar losing

Conference · Tue Jun 01 00:00:00 EDT 1993 · Bulletin of the Ecological Society of America; (United States)

OSTI ID:6234478

Stevens, L ^[1]

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1. Northern Arizona Univ., Flagstaff (United States)

Three modes of plant succession (inhibition, facilitation and tolerance) were tested to explain the replacement of exotic saltcedar (Tamarix ramosissima) by naive phreatophytes in the Colorado River corridor in the Grand Canyon. Dam construction reduced flood frequency and sediment transport, interrupting the [open quotes]perpetual succession[close quotes] of the pre-dam riparian vegetation and initially allowing saltcedar to proliferate. Inhibition results from direct or indirect competition, but field measurements and experiments demonstrate limited evidence of competitive superiority by naive species over saltcedar in three life stages. Field observations and experiments on germination, physiological responses to gradients and comparative life history analyses demonstrate that saltcedar is a stress tolerant, disturbance specialist in an ecologically stabilized river corridor where safe germination sites are increasingly rare. Altered flood frequency, increased soil coarseness and differential herbivory contribute to succession in this system.

• OSTI ID: 6234478
• 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

Related Subjects

13 HYDRO ENERGY
COLORADO RIVER
ECOLOGICAL SUCCESSION
DAMS
BIOLOGICAL EFFECTS
TREES
POPULATION DYNAMICS
CONSTRUCTION
FLOOD CONTROL
HYDROELECTRIC POWER PLANTS
PLANTS
SOILS
SPECIES DIVERSITY
TERRESTRIAL ECOSYSTEMS
CONTROL
ECOSYSTEMS
POWER PLANTS
RIVERS
STREAMS
SURFACE WATERS
130600* - Hydro Energy- Environmental Aspects