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Efeitos espaço temporais da poluição pontual e não pontual em uma bacia hidrográfica subtropical : ecohidrologia como ferramenta de controle
(Universidade Federal de São Carlos, 2015-07-27) Gatti Junior, Pedro; Tundisi, José Galizia; https://lattes.cnpq.br/5730659239785432; https://lattes.cnpq.br/2791182967599526
Contaminants are introduced into aquatic ecosystems, both from point and diffuse sources and usually are deposited in the sediments of lakes and reservoirs. The input of diffuse pollutants in the environment is of difficult control and identification, while the control of point sources is more efficient because they are easily identified. However, the frequent discharges of effluents, althought undergoing treatment, may change the input of elements and substances in a given region. The aim of this study was to assess the spatial-temporal influence of point and non-point source pollution on the characteristics of surface water and sediment in a watershed with well-marked seasons. In addition, concepts and attempts at ecosystems restoration in different regions were reviewed in order to understand the main drivers of abiotic-biotic regulation among watersheds and aquatic ecosystems, based on the principles of Ecohydrology. For this purpose, the concentrations of Cd, Cr, Fe, Ni, Zn, Pb, Al, Cu, Mn, Hg, As, Se, total phosphorus, total nitrogen and ions in water and sediment were examined. Furthermore, levels of metals (Al, Fe, Mn, Cu, Zn, Hg and As) in the sediment profile of stations under of the influence of different impact were evaluated. This study showed that the point source pollution promote a high load of contaminants in sediment, regardless of the season. Furthermore, the point pollution sources seem to be spatially and temporally the main cause of reservoir sediment chemical composition due its frequent effluent release. This study also indicates that, despite several biogeographical differences, hydrology seems to be the main factor that controls the primary and secondary production and sustainability in rivers and lakes (reservoirs). In conclusion, the hydrology in the tropics seems to decrease the expected effects of a higher temperature. Therefore, to increase resilience in tropical freshwaters integrated actions according to hydrological stages are highly recommended.
Heteroptera aquáticos e semiaquáticos (Gerromorpha e Nepomorpha) do sudoeste da Amazônia
(Universidade Federal de São Carlos, 2015-07-27) Vilardi, Gabriel Cestari; Melo, Alan Lane de; https://lattes.cnpq.br/5549358735432795; Strixino, Susana Trivinho; https://lattes.cnpq.br/1804083229761186; https://lattes.cnpq.br/9911642960012466
This study aimed to develop a species list of aquatic and semi-aquatic Heteroptera, including distribution to the world and Brazil and new records, gather information on habitats and habits of genera, present sampling methods and preservation of samples, analyze the influence of environmental variables altitude, vegetation cover, presence within protected areas, environmental integrity (RCE) and preferred substrates on the fauna richness, abundance and composition. 2009 specimens were sampled, of which 1150 have been identified to species level. A list of 73 species of Heteroptera (Gerromorpha and Nepomorpha), distributed in 13 families and 33 genera has been prepared based on surveys carried out for this study and literature. In total there are 34 species of Gerromorpha and 39 Nepomorpha. Of these species, 32 are new records for RO, 13 for the Brazilian Amazon and one for Brazil. For fauna analyzes with environmental variables were analyzed 59 species in 30 genera and 13 families. The species accumulation curve has not reached asymptote, indicating that studied area has greater richness than sampled. The richness found in field accounted for 60% of Jacknife 2. Abundance was related to habitat integrity and water flow. Richness in lotic systems was associated with vegetation cover, solid bedrock and stream size. Habitat integrity and vegetation cover were related to the composition of the studied fauna. The identification keys have 39 genera (19 Gerromorpha and 20 Nepomorpha) arising from collections made for this study and literature review and includes genres not covered in previous studies for the Brazi lian Amazon.