Tuesday, November 14, 2006

Simulating Temporal and Spatial Variability of Forest Carbon Fuxes at Oyster River area, Vancouver Island, Canada.

Ziyu Wang and Robert Grant. Dept. of Renewable Resources, Univ. of Alberta, Edmonton, AB T6G 2E3, Canada

    The objective of this paper is to conduct landscape-level simulations of forest carbon fluxes at Oyster River area using the historic climate data from 1920 to 2004 and maps of soil types, vegetation, disturbance, and topography.  The hourly climatic data were generated from the daily data: (1) solar radiation: measured daily integral distributed over calculated daylength using sine wave; (2) air temperature: the maximum and minimum measured values distributed using sine waves from the minimum at dawn to the maximum at 3 hours after solar noon. (3) humidity: calculated from dewpoint temperature assumed equal to the minimum daily temperature from archives. (4) wind speed: daily measured values assumed constant within day; (5) precipitation: daily measured values assumed to fall from 3:00 to 4:00 pm. GIS input data layers of soil, vegetation, cut, fire and fertilization were georeferenced and converted to 100m×100m grids. The soils, topography, plant species, and disturbances in these 2500 grid cells have been resolved into 550 unique combinations of soils, topography and disturbances, each of which would be represented by one model run. To generate these combinations, soil types in each polygon were allocated to grid cells in the polygon according to their relative presence in the polygon. Slopes, tree species, and dates of harvests, fires and fertilization were taken from the digital disturbance map. Key model outputs include wood biomass for comparison with wood inventory measurements, and CO2 and energy fluxes for comparison with eddy covariance measurements in grid cells within the tower fetches.