Landforms, Disturbance, and Ecotones

Ecotones are transition zones between adjacent vegetation communities (patches) that differ in composition and/or structure. Factors creating patterns in species distribution or vegetation structure within landscapes necessarily create ecotones. Forman and Godron (1986) distinguish environmental resource and disturbance patches, and we apply this concept to ecotones by distinguishing ecotones resulting from spatial variation in availability of resources from ecotones created by disturbance. In this chapter, disturbance refers to an ecotone-forming event of sufficient intensity and severity to create a patch (minimum area ca. 0.1 ha) that differs from preexisting and neighboring vegetation in structure and/or composition.