971 resultados para Southern Brazilian shelf
Resumo:
The temporal and spatial variation of Paralonchurus brasiliensis density (fish per m(2)) in relation to environmental factors was studied on the coasts of Ubatuba and Caraguatatuba, south-eastern Brazil. The fish were collected by shrimp fishery trawl on a monthly basis from January to December, 2002. Seven depths were previously established and for each one the temperature, salinity, organic matter content and grain size of the sediment (phi) was measured. The seasonal analysis of temperature and salinity indicated the presence of the water masses South Atlantic Central Water (SACW) and Coastal Waters (CW) acting in the study area. A total of 29,808 fish were collected during the study period. The highest densities were registered during the summer and autumn indicating an association with CW. The fish population moved to shallow depths during the intrusion of the cold water mass, SACW. The highest densities were registered in depths where the sediment composition ranged from fine sand to silt-clay. Thus, the temperature and type of the sediment are the main environmental factors which affect the spatial-temporal variation of P. brasiliensis density in south-eastern Brazil.
Resumo:
Analyses of living foraminiferal and environmental parameters near an outfall at Mar Grosso Beach (Laguna, SC, Brazil) demonstrate its usefulness as indicators of domestic sewage pollution. The low species diversity may be due to sand accumulation in the central part. Higher diversity was noted closer to the mouth of Laguna estuarine system where reduced salinity and higher temperatures indicate freshwater influence, suggesting a relationship between increased diversity and greater availability of terrestrial food. On the basis of foraminiferal diversity and average coliform count the higher values are closer to the mouth of the estuarine system and under the influence of the outfall. Due to the effect of local hydrodynamics, the particulate organic waste derived from the outfall does not settle down locally, and thus, do not accumulate nearby. Our hypothesis is that the fine material derived from the outfall is accumulating on the southwestern and northwestern parts of the beach.
Resumo:
Abstract Background Physical attributes of the places in which people live, as well as their perceptions of them, may be important health determinants. The perception of place in which people dwell may impact on individual health and may be a more telling indicator for individual health than objective neighborhood characteristics. This paper aims to evaluate psychometric and ecometric properties of a scale on the perceptions of neighborhood problems in adults from Florianopolis, Southern Brazil. Methods Individual, census tract level (per capita monthly familiar income) and neighborhood problems perception (physical and social disorders) variables were investigated. Multilevel models (items nested within persons, persons nested within neighborhoods) were run to assess ecometric properties of variables assessing neighborhood problems. Results The response rate was 85.3%, (1,720 adults). Participants were distributed in 63 census tracts. Two scales were identified using 16 items: Physical Problems and Social Disorder. The ecometric properties of the scales satisfactory: 0.24 to 0.28 for the intra-class correlation and 0.94 to 0.96 for reliability. Higher values on the scales of problems in the physical and social domains were associated with younger age, more length of time residing in the same neighborhood and lower census tract income level. Conclusions The findings support the usefulness of these scales to measure physical and social disorder problems in neighborhoods.