%0 Journal Article
%T WATER AND SEDIMENT TOXICITY ASSESSMENT OF THE JABURU RESERVOIR (CEAR¨¢-BR) IN THE SEMI-ARID REGION = AVALIA  O DA TOXIDADE DA ¨¢GUA E SEDIMENTO DO A UDE JABURU (CEAR¨¢-BR) NA REGI O DO SEMI-¨¢RIDO
%A Priscila Maria Dellamatrice
%A Lilian da Silva Costa
%A Milena Viana de Sousa
%A Rinaldo dos Santos Ara¨²jo
%J Holos Environment
%D 2012
%I Universidade Estadual Paulista
%X The reservoirs are the only resource available to people supply in semi-arid region during the dry season. However, these reservoirs are also used for crop irrigation, which is done on the vicinity of the reservoir. Due to the continuous use of fertilizers and pesticides, these products are carried to the water polluting them. The Jaburu reservoir, located in northwestern of Cear¨¢¡¯ State, is used for supplying eight cities and eight villages and districts. Acute toxicity tests were done in this reservoir on water and sediment, using the organisms Daphnia magna, algae Pseudokirchneriella subcapitata and lettuce seeds, and also chronic toxicity test in the water with Daphnia magna. It was assessed three points in three different depths to determine the stratification effect, during the dry and rainy seasons. Acute toxicity was not detected in the water in the all sampled points. In the chronic test, toxicity was detected in both periods, dry and rainy, and it was more severe during the dry season. In the sediment, there was acute toxicity in water during the dry season for only D. magna, while for the other organisms no toxicity was detected. Results showed that the Jaburu reservoir was not severely impacted yet, but the chronic tests showed contamination of water by pollutants in low concentrations, causing long-term effect. Appropriate regulatory management should be done to prevent future impact on this ecosystem. = Os a udes s o o ¨²nico recurso dispon¨ªvel para abastecimento de ¨¢gua da popula  o na regi o semi-¨¢rida durante a esta  o seca. Esse recurso, por¨¦m, tamb¨¦m ¨¦ utilizado na agricultura desenvolvida no entorno do a ude, para irriga  o. Devido ao uso cont¨ªnuo de fertilizantes e pesticidas, esses produtos podem ser carreados para as ¨¢guas, poluindo-as. O A ude Jaburu, localizado na regi o noroeste do Estado do Cear¨¢, ¨¦ respons¨¢vel pelo abastecimento de oito cidades e oito vilas e distritos. Nele, foram realizados testes de toxicidade aguda na ¨¢gua e sedimento, utilizando os organismos Daphnia magna, a alga Pseudokirchneriella subcapitata e sementes de alface (Lactuca sativa). Foi tamb¨¦m realizado o teste cr nico na ¨¢gua com Daphnia magna. Foram analisados tr¨ºs pontos em tr¨ºs diferentes profundidades para verificar efeito da estratifica  o, nos per¨ªodos de seca e cheia. Toxicidade aguda da ¨¢gua n o foi detectada em nenhum dos pontos amostrados. No teste de toxicidade cr nica, foi detectada toxicidade nos dois per¨ªodos, seca e cheia, sendo mais pronunciado no primeiro. No sedimento, houve toxicidade aguda somente no per¨ªodo de seca para D. magna, en
%K Dam
%K Water
%K Sediment
%K Toxicity
%K Pesticide = A ude
%K ¨¢gua
%K Sedimento
%K Toxicidade
%K Pesticidas.
%U http://www.periodicos.rc.biblioteca.unesp.br/index.php/holos/article/view/5282/4937