It includes, therefore, all the circulation spaces, storage, and of exits of water and the material for carried it, that they keep relations with these canals. (Rodrigues & Adami, in: Venturi, 2005, P. Go to baby clothes for more information. 147-148). The fluvial net also call of net of draining or hidrogrfica net is constituted by all the rivers of a hidrogrfica basin, hierarchically linked. He is one of the main mechanisms of exit of the water, main substance in circulation in the hidrogrfica basin. As much the hidrogrfica basin how much to the hidrogrfica net they do not possess fixed dimensions.
A hidrogrfica basin can be subdivided considering the hierarchic orders of its canals. Rodrigues & Adami in: Venturi (2005, p.163) affirms that: the first way of widely applied hierarquizao was considered by Horton in 1945. In this project, the canals without tributaries are considered of 1 order, and, only in the confluence of two rivers of equal order, it adds plus one to ordinance, that is, two canals of same hierarchic order, form a canal of superior hierarchic order. The water is part of the environment, therefore, its conservation and good use are basic to guarantee the life in our planet. It is important to remember that the water is a natural resources, only, scarce, essential to the life and is distributed of different form in the planet. Of the total of the existing water in land alone 0.0067% it is available for the activities of the man and of this percentage alone a part is in conditions of being used. Had to these characteristics it gains relevance the subject of the handling and preservation of the hidrogrficas basins.
The basin is a territory, microcosm delimited for the proper nature. Its limits are courses d? water that converges to one same point. The basins, its natural resources (fauna, flora and ground) and the social groups possess different biological, social, economic and cultural characteristics that allow to individualizar and to command its handling in function of its particularitities and identity.