Publications by authors named "Darcilio F Baptista"

Prompt assessment and management actions are required if we are to reduce the current rapid loss of habitat and biodiversity worldwide. Statistically valid quantification of the biota and habitat condition in water bodies are prerequisites for rigorous assessment of aquatic biodiversity and habitat. We assessed the ecological condition of streams in a southeastern Brazilian basin.

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An image analysis biomonitoring system was used to evaluate sublethal effects of pH on the mean swimming velocity of zebrafish. Responses to stress were tested comparing individual and group responses. Group analysis indicated no effect for all acid pH and for pH 9.

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The purpose of this study was to establish a subsampling procedure for benthic macroinvertebrates to aid in the development of a multimetric index to assess the biological condition of streams. Data from six streams that are considered minimally impaired were used. Subsampling was done using a device divided into 24 quadrats.

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The objective of this article is to present an analysis of the main bioindicators that are currently used to assess the environmental impact of pollution in water resources. The simple quantification of chemicals in the environment is not enough to reveal the real effects of contamination on ecosystems, making necessary the assessment of the biological effects that pollution causes at different hierarchical levels. The bioindicators used in this article on two case studies comprehend different hierarchical levels: in case study 1, three organization levels were utilized: individual, cellular and molecular, to detect the early effects of exposition to environmental pollutants in three hydrographic basins.

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We evaluated behavioral responses of zebrafish Danio rerio exposed to sublethal concentrations of sodium hypochlorite using an image analysis biomonitoring system (IABS). First, the limits of normal variation in swimming activity of zebrafish were determined by monitoring traveled distance of 40 control fishes using the IABS. An acute toxicity test was performed to determine the LC(50(24 h)) for D.

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Our objective is to evaluate the habitat preference of freshwater snails in relation to environmental factors and the presence of the competitor snail Melanoides tuberculatus. In the first phase, snails was collected at 12 sites. This sampling sites presented a degree of organic input.

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Biomonitoring is defined as the systematic use of biological responses to assess environmental changes, usually anthropogenic impacts. In this article we present the conceptual basis and a brief history of biomonitoring as an assessment tool for environmental health. Considering the drawbacks of physical and chemical parameters to assess environmental quality, we pinpoint the need to integrate these analyses with information provided by biological monitoring.

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