ESTIMATING SHORT-ROTATION EUCALYPTUS-SALIGNA PRODUCTION IN HAWAII - AN INTEGRATED YIELD AND ECONOMIC-MODEL

Growth data of Eucalyptus saligna from plantation experiments in Hawai i and South Africa were analyzed to determined relationships between y ield and soil, climatic, and management variables. Detailed investigat ions were made of growing space, fertilization, and site conditions on tree diameter. The independent variables used were growth age, planti ng density, nitrogen fertilizer application, temperature, rainfall and solar radiation, soil nitrogen content and pH value, and site elevati on. The regression equation developed was used to estimate E. saligna yield of various short-rotation strategies and site-specific climate a nd soil conditions. By coupling these site-specific results with a geo graphical information system, yield was then predicted at all location s on the island of Kauai identified as available for biomass plantatio ns. The estimated total land area available and potential biomass are presented. Establishment costs for E. saligna plantations on Kauai ran ged from US $1207/ha to US $1655/ha for different planting densities a nd amounts of fertilizer applied.