Microclimate changes caused by the conversion of a forest into grassland in an area of Brazilian Savanna

The political and social pressures for the brazilian economic development have intensified deforestation once economic activity is based on agribusiness. Natural ecosystems are rapidly being replaced by pastures and plantations, which modify the microclimate and functioning of these ecosystems. Thus, the aim was to evaluate microclimate changes caused by the conversion of a forest into grassland in an area of Brazilian savanna. The experiment was conducted in a forest and grassland from December 2011 to December 2012, in which solar radiation, air temperature, air relative humidity and wind speed were measured. Grassland showed higher values of solar radiation, average, maximum, and minimum temperature, and wind speed in both seasons than forest, except relative humidity. Solar radiation showed seasonality in the grassland with higher values in the dry season, but no seasonality in the forest which showed a slightly higher value in the dry season. Relative humidity showed a strong seasonality in both areas with higher values in the forest during the wet season. The mean air temperature showed no seasonality in both areas, but it was higher during the dry season in the grassland and higher during the wet season in the forest. The maximum air temperature showed seasonality in the grassland with higher values during dry season and it showed no seasonality in the forest with slightly higher value in the dry season. The minimum air temperature was lower in the dry season in both areas, but only forest showed seasonality. The speed wind was higher in the dry season in both areas, but only grassland showed seasonality. The analysis indicated significant microclimate changes, with a significant increase in 87% of solar radiation, 17.5% of mean temperature, 10% of maximum temperature, 23.5% of minimum temperature, and 95.2% of wind speed, and a decrease in 6.7% of relative humidity.