63ª Reunião Anual da SBPC

C. Ciências Biológicas - 10. Microbiologia - 3. Microbiologia

BACTERIOLOGICAL DIAGNOSIS AND TEMPORAL PHYSICO-CHEMICAL VARIATION OF TWO LOTIC ENVIRONMENTS (BLACK AND CLEAR WATER) LOCATED IN THE CITY CANDEIAS DO JAMARI, RONDONIA.

Ivan Brito Feitosa 1,2 André Luiz Prestes 1 Vera Cruz Parada Vasques 2 Eleide Sampaio Froz 2 Maria Alves da Silva Bahia 2

1. Faculdade São Lucas 2. Companhia de Água e Esgotos do Estado de Rondônia

INTRODUÇÃO:

A significant feature of aquatic environments from the Amazon Region is the coloration. Considering the physicochemical characteristics from the amazon waters, they can be classificated as: white waters, clear waters and black waters. This study aimed to perform a bacteriological diagnosis and evaluate physical-chemical parameters from two lotic environment, Preto River (black water) and Candeias River ( clear water), as well compare the level of impacts between those ambient located in the city of Candeias do Jamari, Rondônia state. The area of this environments are situated: Preto River located at 20 Km from the city of Candeias, and Candeias river that cuts across the city area, whose name the city was named because of its surrounding river. The rivers mentioned above have economic importance for the city.

METODOLOGIA:

Collections were made in the months November and December 2010, January and February 2011 in georeferenced stations. In each lotic environment ware defined four sampling stations. The samples were collected with polyethylene weak of 500ml sterilized. In the laboratory were separate 100ml of the sample to perform the bacteria analysis of coliform group, using the card quanti-tray 2000 and a chromogenic substrate. The expression of results were estimated statistically in most probable number (MPN), and the samples were diluted to 10 - ². Also conducted reviews of pH, turbidity, electrical conductivity with potentiometer,turbidimeter and conductivimeter benchtop. Analysis of Chemical Oxygen Demand (COD) and Oxygen Consumed were performed following the methodology of CETESB (1987).

RESULTADOS:

The river of clear water showed values of total coliforms higher than 110% and thermotolerant higher than 103% compared to the black water river and considering all the sampling stations and sampling periods. The results confirm the proceedings of impacts in Candeias River resulting from poor sanitation, urban sewage, and had significant differences in quantities of bioindicators bacteria of water quality between environments. The pH ranged from acid to alkaline from 5.09 to 7.12, and the black water river was predominantly acid with the lowest values. The turbidity in the clear water river ranged from 22.9 to 32.7 NTU and the black water river ranged UNT from 3.03 to 8.33, the electrical conductivity ranged in the clear water river from 15.9 to 26.2 μS.cm -1 and the black water river ranged from 7.1 to 16.0 μS.cm -¹. The chemical demand of oxygen in the Candeias River ranged from 6.0 to 9.0 mgO2, already the consumed oxygen ranged from 2.32 to 3.68 mg / L and the COD in the Preto River ranged from 8.0 to 12.0 mgO2 and consumed oxygen from 4.8 to 6.24mg/L. Physicochemical variations occurred mainly by climatic influence. The months of January and February are the frequent rainfall, which led to less concentration on physical and chemical environments.

CONCLUSÃO:

The research was pioneer in the county Candeias, in relation to bacteriological diagnosis and temporal variation of physicochemical involving both environments simultaneously, and forming a comparative table. We highlight the physicochemical and biological uniqueness of each environment; however it was found the presence of coliform bacteria above the level allowed by the parameters of potabilidade for human use in the Candeias River with significant differences compared to the Preto River, which also has importance for the local population. The data generated and analyzed, especially for the Candeias River, are similar to other aquatic environments that are near cities and that suffer with results from sewage urban domestic effluent. The lack of preservation has brought harm to the economy, health and committed to aquatic biodiversity. For the maintenance and preservation of the quality of lotic environments studied in this work is necessary to carry out projects of basic sanitation and awareness programs for the local community.

Palavras-chave: Lotic environments, Coliform group, Brazilian Amazon.