VALIDATION OF BRAIDED-STREAM MODELS - SPATIAL STATE-SPACE PLOTS, SELF-AFFINE SCALING, AND ISLAND SHAPES

We present a comprehensive approach for validating braided-stream mode ls and apply it to a specific cellular braided-stream model. The appro ach involves quantitative comparison of modeled and natural braided st reams in terms of mio main aspects: the sequential organization of the ir plan patterns studied using their state-space characteristics and t he hierarchical organization of their patterns studied in the framewor k of self-affine scaling. These two aspects of braided streams are com plementary to each other and taken together provide a sensitive test o f the validity of a model of braided streams. The simple model we exam ine produces patterns that are similar to those of natural braided riv ers in terms of both sequential organization and self-affine scaling. This finding supports the conclusion that the nonlinear interactions b etween water and sediment in the model are the primary mechanisms resp onsible for shaping braided rivers in nature.