Repositório RCAAP

Universidade Federal de Minas Gerais

This paper had the objective of applying a methodology which is aimed at the Public School, more specifically to Fundamental Education, as a contribution to the implementation of Environmental Education programs. The target public for this study were fifth grades students attending the state public school Antônio Militão de Lima and their respective teachers. In order to achieve the proposed objectives, a pedagogical intervention which privileged the Theory of Social Representation was established, based on the methodology developed by the educator Marcos Reigota and an interdisciplinary program, whose aim was to arouse the elements involved towards the forming of citizenship and ecological awareness. The teachers were oriented to the importance of collective and interdisciplinary involvement through offering capacitating courses and interaction with local reality. The results obtained demonstrated the true difficulties faced today by the Public Scholl, and their development of program allowed us to conclude that: 1) capacitating courses for teachers could contribute to arousing a mere critical vision of reality in the educator; 2) the results brought a series of information (informal) through interviews as well as through classroom discussions regarding the children s learning. The Theory of Social Representation and methodology of image interpretation were efficient to motivation students, teachers and other involved.

Mussel culture is an important activity in the state of Santa Catarina, where is developed in almost all the bays and roadsteads. This activity places the state in evidence in Latin America s production. However, this development has been spread in a disorganized way, generating environmental impacts, mainly those arisen from bio deposition of organic material at cultivation areas. The main purpose of this research was to evaluate a roadstead under cultivating influences, determining changes in sediment and benthic macro invertebrate s communities. Three sampling points were chosen according to activity time and intensity. Therefore, the level of organic material in the sediment, the structure and composition of the benthic community were accessed. Results showed that sand was the main material in sediment and rough particles are predominant near the shore side. The carbonate, silt and gravel levels were high at intense cultivating areas. However, differences concerning organic materials were not observed between cultivated and non-cultivated areas. The fauna collected was represented by 65 species belonging to 7 phyla, being the ophiurans more frequently found in the samples. Even though there were no meaningful differences between time and place for picking up samples, higher density and abundance occurred during winter and fall within non-cultivated areas, where debris eater s mollusks are highlighted. Higher richness and diversity were detected during winter and summer time in intensively cultivated areas, with great participation of polychaeta species. Results showed that mussel cultures are not causing direct impacts once the wind action promotes a situation of high hydrodynamics in the region and is a determinative factor in sediment constitution and benthic fauna.

Universidade Federal de Minas Gerais

Financiadora de Estudos e Projetos

Financiadora de Estudos e Projetos

Universidade Federal de Sao Carlos

Universidade Federal de Sao Carlos

Universidade Federal de Sao Carlos

Universidade Federal de Minas Gerais

The influence of phytoplankton and their excreted materials in natural waters have been considered important issues among metal speciation studies. This work focused on the potential influence of the high molecular weight materials excreted by dominant phytoplankton species of Barra Bonita reservoir (Anabaena spiroides, Microcystis aeruginosa and Aulacoseira granulata) in the speciation and complexation of Cu and Cd. Therefore, this study comprised field and laboratory studies. Seasonal samplings were made during a period of two years in the reservoir. The total, ionic and organic concentrations of Cu and Cd were determined, as well as the complexation parameters with ligands present in the reservoir water. Also, the dissolved organic carbon and physico-chemical parameters of the water column were obtained. A speciation model was applied to metal complexation parameters and total metal concentrations obtained in field investigations. Laboratory cultures of the selected microalgae were made to obtain high molecular weight excreted materials. In a similar manner, the high molecular weight materials were isolated from the reservoir water. These materials were analysed for metal complexation with Cu and Cd, monosaccharide composition and elemental analysis (C, H, N and S). In the reservoir water, Cd speciation was dominated by ionic species, while Cu was mostly associated to the dissolved organic matter. Seasonal samplings presented Cu ligands with similar complexation parameters for the entire period studied. Cd complexation was not detected in the reservoir water. The speciation model resulted in similar Cu2+ concentration to the mean value obtained in field analyses, and indicated higher Cu association to the ligands of the reservoir water. Cu was complexed by all high molecular weight materials studied, while Cd was complexed solely by the cyanophyte materials. Higher proportions of acid monosaccharides in the high molecular weight materials corresponded to higher Cu and Cd complexation parameters, whereas no relation between C, H, N and S proportions and metal complexation properties of the high molecular weight materials was observed. The excreted materials of dominant microalgae from Barra Bonita reservoir had Cu ligands with intermediate to weak binding strength, as those present in the reservoir water. These results indicate the potential influence of such organic materials in metal speciation, bioavailability and mobility of metals with similar behaviour to that of Cu in the reservoir water.

Financiadora de Estudos e Projetos

Financiadora de Estudos e Projetos

Financiadora de Estudos e Projetos

Financiadora de Estudos e Projetos

The use of biomarkers can provide a great help in the evaluation of the damages caused by pesticides in aquatic organisms. The present study aimed to verify the toxicity of clomazone and ametryn for a tropical freshwater fish Prochilodus lineatus by using different parameters in fish exposed for 96h to clomazone (1, 5 and 10 mg.L-1) and to ametryn, as the commercial product GesapaxR500 or in its pure form, in the concentrations 2.5 and 5.0 mg.L-1, or only to water (CTR). The parameters used were: hematological; metabolic (concentration of glucose); osmoionic (osmolarity and plasmatic Cl-, Na+ e K+); biochemical and genotoxic (DNA damage). Clomazone caused hematological disturbances in P. lineatus as noted in the lowervalues of hematocrit (Hct) in 10 mg.L-1; hemoglobin (Hb), mean corpuscular hemoglobin (HCM) and mean corpuscular hemoglobin concentration (CHCM) in 5 and 10 mg.L-1, which, in general, may indicate anemia. The number of erythrocytes (RBC) presented increased values in the lowerconcentration tested for clomazone, which probable is related to the stress response, with the releasing of immature erythrocytes in the blood stream. Clomazone also activated the detoxification and antioxidant pathways of the tested animals, as shown by the increased activity of the hepatic biotransformation enzyme glutathione-S-transferase (GST) and the antioxidant enzyme catalase (CAT) in 5 and 10 mg.L-1. The reduced activity of glutathione peroxidase (GPx) observed in 5 and 10 mg.L-1 indicated efficient performance of CAT removing the H2O2, or even a competition with GST for the substratereduced glutathione (GSH). The activity of brain acetylcholinesterase (AChE) in P. lineatus was inhibited in the concentrations of 5 and 10 mg.L-1 of clomazone, showing that this herbicide has an anticholinesterasic effect on the studied fish species. Fish exposed to ametrynshowed hematological disturbances such as lower values of Hct in 2.5 and 5.0 mg.L-1 and of RBC in the concentration of 5.0 mg.L-1. The reduction of plasmatic K+ in the concentration of 2.5 mg.L-1, and the hematological alterations mentioned above, may indicate a rupture of the erythrocytes. Fish exposed both to pure ametrynand the formulated product, showed higher values of glucose as a stress response, in both concentrations tested. The two products also caused inhibition of the gill activity of Na+/K+ATPase in 5.0 mg.L-1. The concentration of 5.0 mg.L-1 caused significant decrease in the malondialdehyde (MDA) levels, leading to the conclusion that ametrynor its formulated product do not generate lipidic peroxidation. DNA damages in the erythrocytes of P. lineatus were x observed in the concentration of 5.0 mg.L-1 of ametryn and GesapaxR 500, showing the genotoxicity of ametryn, probably because it binds directly to the genetic material of the fish. The results presented here allow concluding that the pesticides ametryn and clomazone interfere in the functional parameters of P. lineatus and can compromise the health of these animals

Universidade Federal de Minas Gerais

The present study evolved floristic composition, structure and regeneration dynamic aspects of a restinga forest (pluvial sand coastal plain forest), at Ilha do Cardoso, in Cananéia region, São Paulo State, Brazil. Three portions of restinga forest with same physiognomic aspects were selected: restinga of Trilha para o Morro das Almas (MA), Trilha Interpretativa (TI) and Estrada para a Captação (EC). Five strata of forest were sampled in each portion: Tree, Tree/shrub, Shrub/herbaceous, Herbaceous and Lianas. Each portion was analyzed individually and subsequently were analyzed the entirely of the three portions and compared them. At Trilha para o Morro das Almas were sampled 73 species, at Trilha Interpretativa 72, at Estrada para a Captação 56 and totally sample 112, inside them 31 species were common to three portions and 46 restrict only one of them. The three portions of a forest were floristically similar, MA and TI had the highest Sørensen similarity (70,3%), and TI and EC had the less Sørensen similarity (55,5%). When compared the strata in general Tree/shrub and Shrub/herbaceous strata had the highest value of Sørensen similarity, and the Tree and Herbaceous strata had the less similarity. The highest diversity and equability were found in herbaceous strata, and the less in tree strata. The plants of the three portions had majority of species with geographic distribution in south and southeast Brazil regions, and the majority individuals and species were secondary-climax category. The portions of studied forest were in advanced stage of regeneration, and shade-tolerant species were favored. The differences between three portions of a forest were due to natural process common in tropical forests, where the substitution of one tree produce a mosaic of distinct regenerative phases at community that differ in structure and floristic composition. Differences in environment physical conditions, especially edaphic factors, and distinct anthropic interventions are responsible too.

Universidade Federal de Minas Gerais

This study aims to visualize the work performed by women in agriculture. Part assumption that live in a society patriarchal, activities in the life of reproduction are considered less important by do not generate direct income. It has the objective of presenting the reality of rural women workers and the importance of his work for food security and agroecology. Thus verifying, the context of agrarian issues experienced by them; identifying women's access to public policies; confirming the work performed by them; by viewing their forms of agricultural production; and ascertaining conception of agroecology and feminism by women. To analyze this context was used the method of qualitative research. Within the agricultural universe, was only researched women, aiming to evidence their looks over the reality. The research shows that women are being impacted by the agribusiness model and that still find difficult to advance in production in their territories by the difficult access to public policies. Women's work within the production is directed to the subsistence of the family, not being recognized as an indirect source of income; the same is based on an ecologically-based production, generating a diversity of products that ensures the family food security. It is concluded that there is a difference of reality between women that are inserted or not in social organizations; that still facing the limitations caused by the sexual division of labor; and that their work makes a significant contribution in ensuring food security and in the construction of agroecology.