Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Responses of the C[sub 4] grass Schizachyrium and grassland invader Prosopis over glacial to present CO[sub 2] concentrations

Conference · · Bulletin of the Ecological Society of America; (United States)
OSTI ID:6201846

The woody C[sub 3] Prosopis glandulosa and perennial C[sub 4] grass Schizachyrium scoparium were grown along a daytime gradient from 340 to 200 [mu]mol/mol CO[sub 2] to determine effects of the increase in atmospheric [CO[sub 2]] since glaciation on growth, resource use, and competitive interactions of a species from C[sub 4]-dominated grasslands in the US and the invasive legume P. glandulosa. Increasing [CO[sub 2]] stimulated N[sub 2]-fixation and elicited comparable relative increases in leaf photo- synthesis and water use efficiency in the shrub. Production and nitrogen use efficiency increased linearly with [CO[sub 2]] in P. glandulosa plants that were grown alone, but the CO[sub 2] effect was negated in plants grown with S. scoparium. There was no effect of [CO[sub 2]] on production or water use efficiency of the C[sub 4] grass. Rising [CO[sub 2]] may have contributed to the historical proliferation of P. glandulosa on C[sub 4] grasslands where the woody seedlings can rapidly escape competition with grasses.

OSTI ID:
6201846
Report Number(s):
CONF-930798--
Journal Information:
Bulletin of the Ecological Society of America; (United States), Journal Name: Bulletin of the Ecological Society of America; (United States) Vol. 74:2; ISSN BECLAG; ISSN 0012-9623
Country of Publication:
United States
Language:
English