Forest health depends on intrinsic (intra- and interseasonal variation) and external (stress) factors. Any determination of external-disturbance-specific change threshold therefore neces- sitates a calibration for natural variability when sustainability is concerned. This research will evaluate leaf area index as quantitative indicator for vitality, plant-diversity and CO2 sink potential. Models will be established correlating detailed terrain measurements with remote-sensing-derived vegetation indices, incorporating landscape metrics as weight factors.