ABSTRACT
Forest fragmentation is one of the main threats to global biodiversity. Considering artificial changes in ecosystems is essential to understand even natural ecological patterns and processes. A theory overview is performed, including the improvement of concepts and critical analysis, despite the lack of a unifying conceptual framework about forest fragmentation. We also discuss some theories about natural and artificial limits (i.e. boundaries) based on transformations over time and communities/ecosystems retraction and expansion. Ecological succession is briefly discussed using some aspects of Clement’s and Gleason’s conflicting viewpoints and pointing out the need for reviewing some succession models in order to understand some edge effects. About these effects we draft a concise historical perspective regarding the evolution of some concepts. Despite the relatively wide knowledge on edge effects we argue that it is very difficult to predict ecological processes pathways on edges as well as changes on natural patterns.
Key-words:
deforestation; extinction; succession; ecological theory; limits