PREDICTING WATER FLUXES THROUGH FORESTS FROM MONTHLY PRECIPITATION AND MEAN MONTHLY AIR-TEMPERATURE RECORDS

A process-oriented computer model addressing all major water fluxes through forests is introduced. The model is driven by monthly mean air temperature, monthly precipitation, and mean snow fraction of that precipitation. Other data requirements are limited to latitude, proportions of coniferous and deciduous trees in the forest, thickness of each soil layer (forest floor, soil, and subsoil), and clay fraction (or texture) of each mineral soil layer. The number of parameters to be calibrated is kept at a minimum. Parameter calibration is applicable across sites without further modification unless warranted by outstanding physical differences. The model successfully reproduces available data on throughfall, snowpack, forest floor percolate, soil water content, and streamflow from a deciduous forest in Ontario (Turkey Lakes) and a coniferous forest in Quebec (Lake Laflamme).