A crescente atividade agrícola em áreas de mananciais tem causado preocupações quanto à contaminação por herbicidas em áreas agrícolas. O problema se torna mais importante quando a contaminação pode afetar a água para uso humano, como ocorre com a água do Rio Poxim, que abastece a cidade de Aracaju, capital do Estado de Sergipe. O objetivo do estudo foi avaliar o risco de contaminação de águas superficiais e subterrâneas por herbicidas no alto da Sub-bacia do Rio Poxim e detectar a presença dos princípios ativos Diuron e Ametrina, à montante das plantações de cana-de-açúcar. A análise de risco foi realizada mediante critérios da Environmental Protection Agency (EPA), índice de GUS e método de GOSS. Observou-se que vários princípios ativos sofrem risco de lixiviação, demonstrando a importância do monitoramento do rio para controle tanto da qualidade da água como da frequência e volume de herbicidas aplicado na região. A partir do resultado, foi realizado um monitoramento bimensal de julho de 2009 a julho de 2010, em dois pontos de amostragem. As amostras de água foram analisadas em laboratório, onde se, constatou a presença de Diuron e Ametrina. A qualidade da água na Sub-bacia do Rio Poxim está sendo influenciada pelo uso de herbicidas na região. Ocorreu um aumento nas concentrações dos herbicidas na água superficial, durante o período chuvoso, provocado possivelmente pelo escoamento superficial.Arquivo binário agfomento.txt coincide com o padrã

Contamination of water body by diffuse and point sources in springs has caused concerns mainly due to restrictions on its quality. The problem becomes more serious when contamination affects water for human consumption, as occurs in the river São Francisco, which supplies several municipalities of Sergipe. In this sense, the objective of the study was to evaluate water quality in eleven tributaries of the São Francisco river in its low course in the period from 2013 to 2014, in order to subsidize decision making by public management bodies operating in the region. For this purpose, it was used the Water Quality Index (WQI) and the Trophic State Index (TSI), as well the hierarchical grouping techniques associated to the samples to compare the different causes of contamination of each source. The lowest WQI values were observed in the rivers Betume and Jacaré and they were associated with high concentrations of coliforms related to the disposal of domestic effluents from the riverside cities. It was observed a tendency to eutrophication in the Jacaré stream, Santo Antônio, Pilões, Papagaio and Capivara rivers demonstrated by the high TSI in the rainy season. The results of the cluster analysis were close to their Euclidean distance, and showed that there were similarity relationships between the different water sources related to their parameters of water quality. In this piece of work, we also used the Factor Analysis resulted in the selection of five factors of water quality indicators which are mainly related to mineral content, organic matter, surface runoff and the level of pollution. Thus, it is concluded that the water quality of the São Francisco river tributaries is at a strong tendency towards contamination and that its tributaries need a constant monitoring for the environmental management decisions to be the most adequate for the sustainable survival of the riverside communities.

COMPARAÇÃO ENTRE MÉTODOS DE ESTIMATIVA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA (ETO) NO MUNICÍPIO DE RIO REAL-BA

The study of regeneration and maintenance of spring areas is fundamentally important for the conservation of water resources. Considering the need for restoration of the surrounding areas of the springs of the sub-basin of the Piauitinga River, in Lagarto-Sergipe, this study aimed to characterize the soils in their local environment which will serve as a benchmark for future comparisons between areas of springs already degraded and in the recovering process. The springs were classified according to their origin and their stage of preservation. For the study of the local soil, reforested areas of each spring were selected and grouped according to their position in the landscape. The soil classification of the study sites was performed based on local landscape observation, description of opened micro-trenches and analyses of soil samples. The soils were described and classified morphologically. It was observed that from 22 analyzed spring areas, only two (9%) were considered according to their origin as diffuse and the remaining twenty (91%) as punctual. Considering the preservation stage five spring areas (22%) were identified as disturbed and the other ones as degraded (88%). The sites around the springs’ headwaters of the upper course of the Piauitinga river basin are located in erosion spots, depressions and a single case in the foothills coastal tablelands. The most striking characteristics of local soils are the strong hydromorphic (Gleissolos and gleic Cambisols) and, or, the low level of development (Cambisols and Plinthosols, both with much skeletal material, many of them in eroded phase)

Avaliação do risco de contaminação hídrica por agrotóxicos no Perímetro Irrigado Betume no Baixo Rio São Francisco - DOI: 10.7127/rbai.v9n300301