To model estimates of PERs requires integration of: (1)climatic attribute data (2)Topographic attribute data (3)Substrate attribute data Climate and topography-two of the major influences on plants and animals Climate provides inputs to all PErs precipitation, evaporation, radiation, temperature Topography affects climate locally(slope, aspect, horizon-shading) and regionally ( orographic rain, temperature lapse rates) affects water flow and soil water availability and nutrient availability• To model estimates of PERs requires integration of: (1) Climatic attribute data (2) Topographic attribute data (3) Substrate attribute data • Climate and topography - two of the major influences on plants and animals • Climate provides inputs to all PERs - precipitation, evaporation, radiation, temperature • Topography affects climate locally (slope, aspect, horizon-shading) and regionally (orographic rain, temperature lapse rates) - affects water flow and soil water availability and nutrient availability