Análise das intervenções antrópicas no manguezal do rio Cachoeira, Ilhéus, Bahia

Abstract

The mangrove of the Cachoeira River is larger one of the county of Ilhéus, Bahia, Brazil. It possesses in its limits, urban, agricultural and suburban spaces, which provoke a range of impacts of the most varied forms. Aiming to characterize this mangrove, we used geoprocessing techniques, identification of possible tensors and phytosociologic parameters, and we searched correlations with spatial dynamics, its structure and established structure and parameters, and its relations with the tensors of human origin. It was observed that, along a 21 years period (1987, 1994, 2001 and 2008), the urban mesh went in direction to the mangroves of the left margin of the Cachoeira River, well-known as the Teotônio Vilela district, suppressing some parts of this ecosystem. On the other hand the mangrove areas located on the right margin of the river did not suffer notable modifications of the space. The main impacts currently incident to the mangrove of the Cachoeira River are directly (negatively) linked to the Teotônio Vilela district, as earthworks, cuts, solid effluents; and (positively) to the agricultural zone, due firstly to the preservation of the Atlantic forest remnants and the cacao tree culture system. Although the offensive noticed, the mangrove vegetation showed a structural characteristic pattern of areas naturally environmentally stressed, as the type of sediment or distance to the sea. Remaining the alteration pattern that occurred in recent years, it is expected that the Cachoeira River will have each time less mangrove on its left edge and conserved on its right edge. The monitoring of this possible dynamics and the disturbs that currently occur in the mangrove, the estuary itself and the river basin where they are inserted, as well as of the penalty applications foreseen in the law to the responsible of environmental crimes, so that this scheme becomes mitigated. This problematic shows to be a social question, and its solution looks for this end. While nothing is done, the county gains space close to the urban center, while in the same time, it loses a valuable ecosystem, with possible social problems in a next future.