Figure 1

Metapopulation Concept: Collections of local populations of different clones interact in a niche-matrix view of a microenvironment via dispersal of individuals among niches (large ovals). The niches are numbered from 1-5, starting in the upper left. Each niche can be empty, or inhabited by on or more clones i, represented by small shaded ovals. The clones are numbered 1-4 with #1 annotated with cross hatches, #2 with diagonal bricking, #3 with diagonal stripes and #4 with speckles. Arrows depict the movement of clones by migration, extinction and recolonization, as the case may be, within the microenvironment. Despite local extinctions the metapopulation may persist due to recolonization. Suitable niches can be occupied or unoccupied. Metapopulation models are based on niche occupancy over time. Distinct clones with fixed growth characteristics are in competition. Exogenous disturbances (D in Equation 2.1) which deplete specific clones may influence proportions of the surviving clones.