Caracterização sazonal das propriedades ópticas inerentes nos reservatórios de Barra Bonita e Nova Avanhandava, São Paulo

In order to verify the effect of a cascade system in the water quality of two tropical reservoirs in Brazil, this work proposed to make use of the inherent optical properties (IOPs). From upstream to downstream, Barra Bonita (BB) is the first in a set of six reservoirs along Tietê River and Nova Avanhandava (Nav) is the fifth reservoir. BB is eutrophic whilst Nav is an oligo to mesotrophic environment. According to the IOP analysis, it was possible to observe that BB was organic matter dominated and Nav was inorganic matter dominated. The factors that control the nature of both water composition can be attributed to land use and land cover of the watershed as well as the type of operation system, type of soil, anthropogenic activities and so forth. These differences are noticeable in bio-optical modeling, therefore we must consider different approaches to retrieve water quality parameters in both sites, once, the models take into account the specific information about the IOP and their relation with the optically significant components (OSCs) concentration. In addition, the results of this research can provide comparable data to other water systems and improve the comprehension about the optical properties of complex water bodies.