Aplicação do índice de sustentabilidade de bacias hidrográficas no rio Piranhas-Açu a partir dos métodos multicritério e multideciso.

Abstract

The issue of water resources in the world today and especially in semi-arid regions is a crucial issue in overcoming obstacles to sustainable development. The problem previously dealt with in a sector nowadays with the advancement of scientific thinking on the issue has pointed to an analysis focused on the whatershed as a unit of management in all its aspects and especially with regard to popular participation in the process of decision-making. As an alternative to this fact, we have sought the elaboration of indicators aimed at trying to measure sustainability and, besides the elaborated methodologies, it is perceived that there is a lack of methodologies that besides contemplating the whatershed make possible the public participation in the decision making. With the objective of presenting an alternative to this problem, the present research aimed to develop a methodology based on the indicators of the Watershed Sustainability Index (WSI) applied together with Multicriteria and Multidecisor analysis to contemplate a greater public participation in the Decision-making. The developed model was composed of fifteen indicators distributed in three dimensions (Pressure-State-Response), having an initial phase composed by the calculation of the indicators of the Watershed Sustainability Index, followed by the application of Multicriteria analysis (method PROMETHEE - Preference Ranking Organization Method For Enrichment Evaluation II) and Multidecisor (COPELAND method) based on the values of the indicators. The site of application was the Piranhas-Açu basin (more specifically, its eleven sub-basins), located entirely in the Brazilian semi-arid considered the most problematic in the world. The results demonstrate that the applicability of Watershed Sustainability Index indicators together with the Preference Ranking Organization Method For Enrichment Evaluation (II) method and the COPELAND method for the definition of an evaluation scale, or index, bring relevant results to This context. The ordering obtained through the method emphasizes that there is inequality between the sub-basins part of the Piranhas-Açu basin, highlighting the Pataxó sub-basin as less sustainable and the Média Piranhas Potiguar sub-basin as more sustainable. It should be noted that this scenario is still far from ideal in terms of water resources management even in sub-basins that present satisfactory levels.