Utilização do sensoriamento remoto na avaliação das características limnológicas do reservatório de Itaparica, no sub-médio rio São Francisco

Abstract

The land inhabitants generally cause environmental impact on the marginal areas where they live in. For this reason, the evaluation of limnologic data of water bodies through remote sensing can bring information on environment aspects in a synoptic and periodic fashion. Taking into account this fact, the work aimed to study the limnologic characteristics of the Itaparica reservoir, São Francisco River, Bahia state, Brazil. Interpretation of orbital images was used to provide information on the local hydrologic characteristics. These satellite images were integrated with in loco data that posed optically active character. The results showed that urban organic loads (high values orthophosphate) and chemical fertilizers (high values ammonia) originating from soil runoff in irrigated areas, along with gallery forest degradation and soil erosion, were the main factors influencing the water’s physical and chemical characteristics. Such information was utilized to evaluate the environmental alterations that took place in the area. On the otherhand, the results also showed that remote sensing, with sensors Landsat series, has drawbacks regarding spectrometric studies on water. Therefore, further studies are needed to boost this research field.