Ludmila Bardin

VARIAÇÃO ESTACIONAL DA RADIAÇÃO SOLAR EM AMBIENTE EXTERNO E NO INTERIOR DE FLORESTA SEMIDECÍDUA 1

Daily solar radiation measurements were taken below the canopy of a semideciduous forest and at an open site. The mean values obtained during the period of measurements (June, 2000 to January, 2001), were 1.1 and 19.3 MJ/m 2 /d, respectively. The transmission of solar radiation to the forest understory was influenced by the season of the year and varied from 3.3% in the summer to 8.2% in the winter. Regression equations were developed taking into account the differences among the seasons to estimate the solar radiation inside the forest as a function of the open site values.

Diferenças estacionais entre variáveis microclimáticas para ambientes de interior de mata, vinhedo e posto meteorológico em Jundiaí (SP)

Studies aiming the characterization of microclimatic variability are important for evaluating forest and vineyards management. Therefore microclimatic measurements of: air temperature, relative humidity and wind speed were taken, at Jundiai, State of Sao Paulo, Brazil. The following environments were evaluated: semideciduous forest interior, ´Niagara Rosada´ vineyard and standard weather station. Seazonal variation comparison was performed using daily data collected by automatic weather stations during the following months:August, 2000 (winter), October, 2000 (spring) and January, 2001 (summer). The internal microclimate was modified at semideciduous forest, with a decrease of maximum air temperature by 1.0 °C, 1.9 °C and 3.4 °C, respectively for winter, spring and summer; an increase of air relative humidity from 4-7%, and a reduction of wind speed in all evaluated seasons. The minimum air temperature inside the forest was 0.2 °C higher than at the standard weather station during summer, and 1.2 °C lower during winter. On the other hand, the vineyard lead to an increase of 0.5 °C to 1.0 °C on the maximum air temperature and to a decrease of 2% on the relative humidity when compared to standard weather station environment.