Claudia Fernanda Almeida Teixeira

Relações intensidade-duração-frequência obtidas a partir de séries anual e de duração parcial para a localidade de Pelotas-RS

The intensity-duration-frequency occurrence ratio (IDF) is a tool commonly used for precipitation-runoff data transformation, which is established from observations of intense precipitations over a period sufficiently long as to allow the occurrence of extremes at the observation site. This study focused on verifying the existence or absence of new data, in terms of IDF ratio, by using partial duration records produced from data on maximum daily disaggregated rainfall for pre determined durations. The partial duration records considered a base value of 55 mm, totaling 279 values. After the rainfall series were established, their independence and seasonality were assessed. Using the Students t-test statistics, it was established that no new data, as IDF ratio, emerged from the analysis of the partial duration series with the recommended base value of precipitation, as compared to the historical records.

Runoff hydrogram resulting from the methodology employed to record precipitation.

Data of daily precipitation recorded by pluviometers are more easily found than those from pluviographic data. This often constitutes a limitation for hydrological applications such as the rainfall-runoff transformation, which needs to feed on short duration precipitation data. To overcome this constraint, the development of disaggregation models for daily precipitation has been sought for a long time. The aim of this study was to compare different runoff hydrograms resulting from hyetogram estimates from Intensity-Duration-Frequency (IDF) relationship between pluviometric and pluviographic data for the location of Pelotas, RS-Brazil. The relationship method was used to calculate daily precipitation disaggregation, while the runoff depth and its propagation were over a 7 km2 area and were determined through the methodology proposed by SCS (1972). The findings lead to the conclusion that the peak runoff values showed a difference of 12.6, -4.4, 21.8, 38.7, 54.3 and 58.2%, for return periods of 2, 5, 10, 20, 50 and 100 years, respectively, when calculated through the IDF ratio, as compared to the analytical equation.

Fornecimento de cálcio para plantas de eucalyptus saligna por meio de aplicação de resíduo industrial lama de cal

The industrial waste lime sludge originated from the production of bleached kraft paper from eucalyptus, contains considerable amount of calcium, which can help reduce the consumption of fertilizers in forest plantations. To evaluate the effect of lime sludge as a Ca source and its effects on nutrient availability and shoot dry matter production of eucalyptus trees, two greenhouse experiments were conducted in the research area of Klabin, in Parana. The soils were an Entisol quartzipsamments and an Alfisol paleudult. The treatments consisted of two Ca sources (dolomitic limestone and lime sludge), and a control, identified as: Entisol control, Entisol limestone, Entisol lime sludge and for the Alfisol: Alfisol control, Alfisol limestone, and Alfisol lime sludge. The experimental design was completely randomized with four replications. Seedlings of Eucalyptus saligna were grown for 126 days in pots. The dry matter production was quantified, shoot leaf analysis conducted and soil analyzed at harvest. The data revealed that both types of liming supplied the eucalyptus plants with Ca, increased by the residue application, compared with the treatment with dolomitic limestone, whereas the N, P, K and S contents remained similar. The foliar Mg contents of plants grown in the treatments Entisol control and Entisol lime sludge were below the range considered adequate. The addition of lime sludge increased soil pH and Ca and Na concentrations, reduced exchangeable Al and did not affect Mg availability; this latter fact can lead to Mg deficiency for plants in soils with low Mg levels, as observed in this study.