Windthrow Hazard Mapping using GIS, Canadian Forest Products ...

Table A1-2. Map formulas used to calculate windthrow risk for WTT3010 modelwithout time since logging (timelog)MAPCALCULATION1( (180.AsGrid * 0.00697) - (7.5842.AsGrid) - ([Slp100] *0.034) + ([Ht] * 0.0507) + ([Mwspeed] * 0.1824) + ([Strmaxs]* 0.1918) - (5000.AsGrid * 0.00012) + (4.AsGrid * 0.3249))MAPCALCULATION (2.71828.AsGrid.Pow([Map Calculation 1]))2MAPCALCULATION ([Map Calculation 2] / ([Map Calculation 2]+1))3VARIABLES: a) [BRGP] held constant at 180b) [SCORE] held constant at 5000c) [DIREX] held constant at 4with time since logging (timelog)MAPCALCULATION1( (180.AsGrid * 0.00778) - (6.9186.AsGrid) - ([Slp100] *0.0264) + ([Ht] * 0.0494) + ([Mwspeed] * 0.0944) +([Strmaxs] * 0.1374) - (5000.AsGrid * 0.00008) + (4.AsGrid *0.3350) + (10.AsGrid * 0.0462))MAPCALCULATION (2.71828.AsGrid.Pow([Map Calculation 1]))2MAPCALCULATION ([Map Calculation 2] / ([Map Calculation 2]+1))3VARIABLES: d) [BRGP] held constant at 180e) [SCORE] held constant at 5000f) [DIREX] held constant at 4g) [TIMELOG] held constant at 1022