Fig. 2. Illustrative example of nonlinearities and thresholds in a Swiss mountain wooded pasture: impact of cattle activity on seedlings (< 1 year old), saplings (1-3 years), and browsed trees (4-8 years) relative to other survival and growth limiting factors. Trees were exposed to low (solid line) and high (dotted line) grazing pressures. Arrows indicate a higher (up) or lower (down) impact of cattle, which varies by deciduous (Acer pseudoplatanus, Fagus sylvatica) and coniferous species, (Picea abies and Abies alba). The impact of grazing increases with higher development stages and high grazing pressure. In contrast, low grazing pressure reduces the relative importance once the seedlings have developed to browsed trees. Deciduous species are generally more vulnerable to cattle activity, with the exception of the sapling stage when coniferous species are more sensitive. With changing management regimes, different tree species will show nonlinear survival and growth rates that may result in species shift under changing climatic conditions.

Fig. 2