Ozone and simulated acid rain effects on growth root hydraulic conductivity, and photosynthesis of red spruce

Conference · Wed Apr 01 04:00:00 EST 1987 · Plant Physiol., Suppl.; (United States)

OSTI ID:6060211

Lee, W S; Chevone, B I; Seiler, J R

Three-year-old red spruce seedlings were exposed to ozone (O/sub 3/) at 0.00 (control) or 0.10 ppm, 4 hr/d, 3 d/wk in combination with simulated rain (pH 3.0 or 5.6, 1 hr/d, 2 d/wk at 0.75 cm/hr) for 10 wks. All seedlings were submitted to two drought cycles after the 10-wk-treatment. O/sub 3/ significantly decreased root hydraulic conductivity (Lp) by 21% after 10 wks across all rain pHs. The reduction of Lp in seedlings treated with O/sub 3/ was enhanced by drought stress. Rain pH alone did not affect Lp during the 10-wks-exposure and drought cycles. However, the O/sub 3/ effect on Lp was more severe at pH 5.6 than at pH 3.0. Rain at pH 3.0 stimulated shoot height growth by 31% compared with pH 5.6 across all O/sub 3/ treatments. However, root, shoot, and total dry weight of seedlings were not changed by any treatments. Neither O/sub 3/ nor rain pH affected net photosynthetic (P/sub i/) response to branch water potential in plants subjected to one or two drought cycles. However, P/sub i/ was less sensitive to water potential after two drought cycles, indicating physiological adjustment to drought stress.

• Research Organization: Virginia Polytechnic Institute and State Univ., Blacksburg
• OSTI ID: 6060211
• Report Number(s): CONF-8707108-
• Conference Information: Journal Name: Plant Physiol., Suppl.; (United States) Journal Volume: 83:4
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ABSORPTION
ACID RAIN
ATMOSPHERIC PRECIPITATIONS
BIOLOGICAL ADAPTATION
BIOLOGICAL STRESS
CHEMICAL REACTIONS
CHRONIC EXPOSURE
HYDRAULIC CONDUCTIVITY
HYDROGEN COMPOUNDS
OXYGEN COMPOUNDS
OZONE
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANTS
RAIN
ROOT ABSORPTION
ROOTS
SEEDLINGS
SPRUCES
SYNERGISM
SYNTHESIS
TOXICITY
TREES
UPTAKE
WATER