Effects of acidic rain and ozone on nitrogen fixation and photosynthesis in the lichen lobaria pulmonaria (L. ) Hoffm

Technical Report · Tue Dec 31 23:00:00 EST 1985

OSTI ID:5881585

Sigal, L L; Johnston, J W

The lichen Lobaria pulmonaria was subjected to ozone fumigations at 118, 235 and 353 mcg/cu m and simulated acidic rain at pH levels of 2.6, 4.2 and 5.6 for 5 days (M,W,F,M,W) during a 10-day period. Acidic rain at pH 2.6 caused significant reduction in nitrogen fixation and gross photosynthesis of 100 and 90%, respectively, and thallus bleaching was apparent. There were no significant differences between the pH 5.6 and 4.2 treatments in either gross photosynthesis or nitrogen fixation, and the color of the lichen thalli was unchanged. The effect of ozone on nitrogen fixation and photosynthesis over the range of concentrations used was not significant, but there was a trend toward reduced nitrogen fixation with increasing O/sub 3/ concentration. There were no significant ozone-acidic rain interactions. The threshold for response to rain acidity for L. pulmonaria lies between pH 2.6 and 4.2, and the acidity of wet deposition in parts of the United States may fall in the range.

• Research Organization: Oak Ridge National Lab., TN (USA). Environmental Sciences Div.
• OSTI ID: 5881585
• Report Number(s): PB-88-104294/XAB
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
560300 -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACID RAIN
ACIDIFICATION
AIR QUALITY
ALGAE
ATMOSPHERIC PRECIPITATIONS
BIOLOGICAL EFFECTS
CHEMICAL REACTIONS
ENVIRONMENTAL IMPACTS
ENVIRONMENTAL QUALITY
FUNGI
LICHENS
NAPAP
NITROGEN FIXATION
OZONE
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANTS
PRECIPITATION SCAVENGING
RAIN
SEPARATION PROCESSES
SYNTHESIS
WASHOUT