Heterogeneity versus Mosaic and Disorder versus Order

Heterogeneity may be considered as a nonscalar image (far from the focus) of the environment, and when patterns emerge from heterogeneity, that emergence represents the focal point for that perception. In effect, heterogeneity per se is the status of the medium in which a species occurs, but we need to find the scaled dimension to perceive patterns. This means we must find patches and organization in a selected domain. In Fig. 3.4 a subset from a mountain pasture has been classified by using an automatic classifier. When the image is classified using 200 categories, the heterogeneity emerges. As we decrease the number of categories progressively, different patterns appear and a mosaic is represented (shrubs and fields). As stressed also by Wiens (2000), heterogeneity per se is not sufficient to describe a pattern; it is necessary to relate the heterogeneity with organisms.

Heterogeneity is a property of every matrix (medium), but without a scaling action such heterogeneity is simply a noise.

The human perception of heterogeneity can be associated with a disordered way to perceive the surroundings. Most of our surrounding is perceived as structures to which we can not attribute a precise function, and as a consequence these structures are objects without meaning that contribute to the background noise. The mosaic can be the result of disorder processes like fragmentation or conversely the result of a new order imparted to the system from outside drivers (Fig. 3.5).

Mosaic creation can be observed in different stages of evolution of a system: when a homogeneous system is heavily disturbed, like during fragmentation (sensu lato), and when a system evolves toward a more ordered system after a long undisturbed period. Shapes of these two types of mosaic could be very similar but the ecological processes are completely different. In the first case, we can call this mosaic far from order and, in the second case close to order.

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