Projection of response of trees and forests to acidic deposition and associated pollutants

Technical Report · Sat Sep 01 00:00:00 EDT 1990

OSTI ID:6183039

Kiester, A R; Ford, E D; Avery, A; Gay, C; Droessler, T

In 1986 the National Acid Precipitation Assessment Program (NAPAP) established the Forest Response Program (FRP) to assess the effects of acidic deposition and associated pollutants on forests. Modeling studies were developed in parallel with both field studies on the pattern and trends of forest condition and physiological studies of seedlings, saplings, and branches of mature trees. The goals of the modeling effort were to simulate the dynamics of the processes by which acidic deposition and ozone affect tree physiological processes and therefore lead to changes in growth. Results from models of the physiological function of leaves, branches, roots, xylem, and canopies are presented here. These models illustrate three aspects of the dynamics of these processes. First, growth and the effects of pollutants are stochastic processes; that is, they vary randomly over time. The models help to account for the large amount of variability seen in normal field conditions. Second, some physiological processes can compensate for the effects of acidic deposition or ozone. Third, pollutants may have more than one effect on tree growth, and these effects may be synergistic. The potential nonlinearities and the variabilities demonstrated by these models lead to the conclusions that forest health effects may be developing that are not yet apparent; and for regulation of acidic deposition and associated pollutants to have a detectable effect, regulatory changes will probably have to be of substantial magnitude.

• Research Organization: NSI Technology Services Corp., Corvallis, OR (USA)
• OSTI ID: 6183039
• Report Number(s): PB-91-136572/XAB
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
01 COAL, LIGNITE, AND PEAT
ACID RAIN
TOXICITY
FORESTS
PRODUCTIVITY
OZONE
POLLUTANTS
EMISSION
ENVIRONMENTAL EFFECTS
TREES
SENSITIVITY
AIR POLLUTION
MATHEMATICAL MODELS
NAPAP
STOCHASTIC PROCESSES
SYNERGISM
ATMOSPHERIC PRECIPITATIONS
PLANTS
POLLUTION
RAIN
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)
560300 - Chemicals Metabolism & Toxicology
010900 - Coal
Lignite
& Peat- Environmental Aspects