SCALE AND GENERAL LAWS OF VEGETATION DYNAMICS

In the recent theoretical proposal of S. T. A. Pickett and colleagues, a patch dynamic concept of secondary succession is used to develop ge neral laws of vegetational change. While this proposal is an important step in the formalization of vegetation theory, its basis in secondar y succession limits its applicability at larger spatial or temporal sc ales than those of single disturbance patches. We show that general th eory must incorporate a more inclusive concept of environmental constr aints on species behaviors than advanced in their proposal, as well as an expanded account of those behaviors. Our modifications of the orig inal proposal allow its unrestricted applicability at all scales relev ant to vegetation dynamics, and emphasize the fundamentally continuous , interactive nature of these dynamics.