Scaling the Mosaics by Species

It seems that three contexts are possible:

The first context is one in which the presence of an organism is conditioned by favorable conditions like water availability, soil fertility, and micro-climate. This seems quite a "passive" status in which an organism is enveloped. For a plant this could be the seed germination after dispersal from the mother plant; for an animal, the selection of a territory in which to reproduce.

A second step is represented by the direct interception of the species-specific eco-field in the context. This step depends greatly on the species considered. For a plant this could be the development of a root system or the shape of the canopy. Both are largely affected by availability of nutrients, by light tenure, by the fungi community in the soil, or by aerial competitors.

For an animal the second step can be represented by the availability of enough food, good reproductive sites, or low interindividual competition.

The third context, which represents the process mosaic, is again like the first one strongly dependent on the context and passively "accepted" by organisms. The economic mosaic can create patches in which timber logging assumes a particular importance for local populations and this in turn favors the reduction of old growth forests. It is not surprising that this process has dramatic effects on many species of animals and plants.

The application of such principles is not too far from the concept of the fundamental and realized niche, but differs by a more detailed analysis of causes and effects.

Two relatively passive contexts form the border to a more active mosaic in which the decision to stay or to move for animals and to reproduce agamically or by clonation is determined more by the interaction of the specific eco-field with that mosaic.

A comparative analysis conducted using such paradigms can be extremely useful to fill the gap between ecosystem ecology, community ecology, and landscape ecology.

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