Chemical inputs to fir trees from rain and clouds at Clingmans Peak, North Carolina

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6942990

Dasch, J M ^[1]

---

1. General Motors Research Lab., Warren, MI (US)

The forest decline that has recently been observed in the eastern United States is limited to high elevation, coniferous ecosystems. The decline may be related to stresses from atmospheric pollution, climate, pathogens, or possibly a combination of the above. The ecosystem receives atmospheric pollution in the form of dry deposited gases and particles or as wet deposition. If air pollution stresses are leading to high elevation forest decline, then dry-or wet-deposited chemical inputs must be greater at these high elevation sites than elsewhere. Dry- deposited chemical inputs are not expected to be a major factor because atmospheric concentrations are probably lower, rather than higher, at sites above the atmospheric mixing layer. One possible exception to this is ozone, which has been observed to increase with altitude. However, chemical inputs from wet deposition may be important, since high elevation sites receive more precipitation than low elevation sites, and may receive additional inputs from immersion in clouds. Cloud water interception is considered a major input at high elevations due to the large fraction of time with cloud immersion, the large interception potential caused by higher wind speeds above the surface, the surface area available for interception in a coniferous canopy and the high concentrations of chemical species present in cloud water. This paper discusses how all of these factors suggest that wet deposition inputs from cloud water interception may be a major stress at high elevation sites.

• OSTI ID: 6942990
• Report Number(s): CONF-880679--
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
560300 -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AIR POLLUTION
AIR POLLUTION MONITORING
AIR QUALITY
ATMOSPHERIC CHEMISTRY
ATMOSPHERIC PRECIPITATIONS
BIOLOGICAL EFFECTS
CHEMISTRY
CONIFERS
DEPOSITION
ECOSYSTEMS
ENVIRONMENTAL IMPACTS
ENVIRONMENTAL QUALITY
FEDERAL REGION IV
FORESTS
GROWTH
NORTH AMERICA
NORTH CAROLINA
OZONE
PARTICLES
PH VALUE
PINOPHYTA
PLANT GROWTH
PLANTS
POLLUTANTS
POLLUTION
SPRUCES
TERRESTRIAL ECOSYSTEMS
TOXICITY
TREES
USA