Succession Process & Climax

Core Ontological Distinctions

Migration is merely the physical arrival of seeds or spores on a bare site. Ecesis is their actual germination, root establishment, and survival to reproductive maturity. Reaction is the autogenic modification of the soil and microclimate by those established organisms—which ironically makes the habitat unsuitable for themselves and paves the way for the next seral wave.

In Facilitation, pioneers actively improve the environment (adding nitrogen/humus) to help late species establish. In Tolerance, late species neither need nor are blocked by pioneers—they simply tolerate deeper shade and lower resources until they outgrow early species. In Inhibition, early occupants actively block all other species (via allelopathy or space monopoly) until a disturbance kills the incumbents.

Monoclimax (Clements) argues that every region has only one true climatic climax. Polyclimax (Tansley) argues that a region supports a mosaic of discrete climaxes governed by soil (edaphic), topography, or fire (pyric). Climax-Pattern (Whittaker) views climax communities as a continuous, intergrading spectrum along environmental gradients without sharp boundaries.