Some models of catastrophic behavior in exploited forests

✍ Scribed by Gatto, Marino ;Rinaldi, Sergio

• Publisher: Springer-Verlag
• Year: 1987
• Tongue: English
• Weight: 678 KB
• Volume: 69
• Category: Article
• ISSN: 1573-5052
• DOI: 10.1007/bf00038703

✦ Synopsis

This paper presents some models which show that small variations of the human exploitation of a natural forest can give rise to dramatic changes in the forest biomass. Two simple mechanisms for catastrophes, already pointed out for other ecosystems, are briefly discussed at the beginning of the paper. A more interesting mechanism for catastrophes is then presented. It is based on a model of the dynamics of forest biomass and soil nutrients and on the fact that mortality may become very high when soil acidity exceeds a threshold. In particular, it is shown that an increase of the exploitation may give rise to a catastrophic collapse of the forest if the exogenous nutrient inflow, which brings about also acidic deposition, is sufficiently high. Moreover, such a catastrophe is irreversible, i.e., regeneration is not possible, if the nutrient inflow is too high.