proposal to extend the scope of application of the Holdridge's climatic classification

Abstract

Holdridge's Life Zone Model is as useful as simple and elegant. Nevertheless, when we try to apply this ecological classification to some regions of the world, like Argentinean Patagonia and Humid Pampa, by observing the natural vegetation and other important environmental characteristics we can not find a good correlation between the observed and the expected ones. Considering the importance and relevance of Holdridgeís classification, we suggest to modify slightly its basic parameter definitions without modifying the original idea, in order to extend the scope of its application. As Holdridge introduces the concept of "biotemperature", a similar criterion could be used to replace the mean annual precipitation by the alternative parameter "annual effective rain". Results obtained applying the suggested modification indicate that the performance of the model could be improved, with a better correlation between the actual physiognomic and taxonomic characteristics and those expected to be found in the specific life zone.