Some aspects of island ecosystems analysis (a preliminary conceptual synthesis)

Abstract

The point is made that ecological principles generated from the study of continental ecosystems cannot be extrapolated to oceanic islands without reservations. Island ecosystems are not necessarily unique at the level of biome or formation structure, but they differ greatly at the level of life form and species structure, and as such, they differ also in their functional and dynamic relations. The greatest departure occurs in the area of species interaction .Examples of such departures are given in three areas of ecosystem analysis: (1) Spatial distribution of island biota, (2) Niche differentiation, and (3) Successional phenomena. The differences in ecological relationships of oceanic island ecosystems area direct reflection of their special biological evolution, caused by geographic isolation , small habitat size and recent geological age. Perhaps more so than elsewhere, ecosystem analysis is on islands cannot be meaningful without an appreciation of their special evolutionary relationships. However, to some extent this applies also when trying to extrapolate results of ecosystem analysis from one biogeographic region to another. It is suggested that the ecological consequences of different biological evolutions are best recognized by studying ecologically similar species within the context of their general niches and by relating these to the ecosystem as a whole.