Ecological studies on the secondary vegetation of a tropical montane habitat in Mindanao

Abstract

Secondary vegetation may be defined as vegetation developed subsequent to human interference. Any human presence in an area almost invariably produces interference in some degree but the term is used here to describe only catastrophic human interference involving destruction of most or all of the above-ground living plant material. It is probable that even Paleolithic man, by the use of fire, was able to affect much of the earth' s natural vegetation in this catastrophic manner, producing extensive areas of secondary vegetation in regions of dry or seasonally dry climate (Sauer 1956). The advent of agriculture, bringing with it woodland clearance and grazing, must have extended the areas of secondary vegetation greatly particularly in the more humid climates which, until that time, had escaped severe interference. In this way man has been responsible for creating new vegetation types or at least for extending types formerly of minor importance , and it is probable , as Anderson (1956) has pointed out , that he has also precipitated the evolution of many new species which now occupy the unique habitats created by his disturbance.