A computer simulation of ecosystem processes in forests for application to air pollution, acid precipitation and global change
- Lawrence Livermore National Lab., CA (United States)
- California Univ., Berkeley, CA (United States). Dept. of Forestry and Resource Management
We have developed a simulation model, TREE, of the effects of gaseous air pollutants and acid precipitation on the forest ecosystem processes of tree productivity and growth. This model is based on an existing general model of forest ecosystem processes developed for regional application (FOREST-BGC) combined with an existing model of plant productivity and transpiration (BACROS). The former model uses daily and annual time-steps; BACROS uses hourly time-steps and computes gaseous pollutant (ozone) uptake. In FOREST-BGC, we model the effects of ozone by reducing productivity based on the cumulative uptake for each leaf age-class. The model computations convert this reduction in productivity to a reduction in growth. This version of the model restricts consideration of acid precipitation to possible effects on productivity due to foliar exposure. Basic model performance has been studied for ponderosa pine exposed to ozone at the USFS Chico Tree Improvement Center The model simulates observed phenomena such as draw down of soil water during summer months. For ozone levels for the Chico Field Site for the 1990 season, maximum daily ozone uptake occurred in August with peak of 2.2 {times} 10{sup {minus}5} kg m{sup {minus}2} d{sup 1}. Cumulative annual ozone uptake for current year needles was 3.2 {times} 10{sup {minus}2} kg m{sup {minus}2} producing a 12.6% reduction in productivity for current year needles and a 13.3% reduction in chlorophyll and effective leaf area. Total transpiration was 0.95 m. The model is now being used to develop a terrestrial ecosystem submodel for a global scale Earth System Model (ESM) that integrates interacting atmospheric, oceanic, and land system components. Algorithms from the forest model will support feedback calculation of the effect of forests on atmospheric physics and chemistry as well as calculate effects of climate- and C0{sub 2}-change on forest productivity.
- Research Organization:
- Lawrence Livermore National Lab., CA (United States)
- Sponsoring Organization:
- USDOE; USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 7288861
- Report Number(s):
- UCRL-JC-108957; CONF-920771-5; ON: DE92019616
- Resource Relation:
- Conference: 1992 summer computer simulation conference, Reno, NV (United States), 27-30 Jul 1992
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
POLLUTANTS
BIOLOGICAL EFFECTS
TREES
PLANT GROWTH
ACID RAIN
AIR POLLUTION
ATMOSPHERIC CHEMISTRY
CHLOROPHYLL
CLIMATE MODELS
COMPUTERIZED SIMULATION
FORESTS
OZONE
TERRESTRIAL ECOSYSTEMS
TRANSPIRATION
ATMOSPHERIC PRECIPITATIONS
CARBOXYLIC ACIDS
CHEMISTRY
ECOSYSTEMS
GROWTH
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
MATHEMATICAL MODELS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHYTOCHROMES
PIGMENTS
PLANTS
POLLUTION
PORPHYRINS
PROTEINS
RAIN
SIMULATION
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)
560300 - Chemicals Metabolism & Toxicology