Changes in the structure due to strong winds in forest areas in the Pantanal, Brazil

Abstract

ABSTRACT:The Pantanal climate presents marked seasonality and eventually strong winds occur, especially in the beginning of the rainy season, which may last from September or October until April. A phytosociological study was conducted to evaluate the effects of a strong wind on the composition and structure of two forest formations in Pantanal wetland, a semideciduous forest (19º 15' 32''S and 55º 45' 23.7''W) and a forested savanna -"cerradão" (19° 17' 21''S and 55º 45' 8.9''W), with trees with diameter at breast height (DBH) ≥ 5 cm. After the strong wind, a reduction of 6% of the basal area and volume in the semideciduous forest was observed, mainly due to the uprooting of Xylopia aromatica trees. In the forested savanna, the basal area and volume reduction was even higher; an estimated 10%, representing 69 uprooted trees per hectare, mainly of Copaifera martii trees. In both areas it was observed that the uprooted trees presented an average height and diameter bigger than the trees that remained intact. Usually, the trees that were uprooted presented higher wood density and the species that had broken branches had a lower density.Key words: Basal area, natural disturbance, savanna forest, semideciduous forest. ALTERAÇÕES NA ESTRUTURA DE ÁREAS FLORESTADAS CAUSADAS POR VENTANIA FORTE NO PANTANAL, BRASIL

Indirect Methods to Determine the Risk of Damage to the Health of Firefighters and Children Due to Exposure to Smoke Emission from Burning Wood/Coal in a Controlled Environment

“…To characterize time and duration of exposure doses, in this study, we established EF as the exposure frequency (120 days year −1 ) and ED as the exposure duration (6 years for children and 24 years for adults). Here, the 120 days was considered, as it corresponds to the period of days that remains the dry season in which the highest number of fires occurs in Brazil, that is, between the months of July and October [ 34 , 37 , 38 ]. Therefore, the results can be considered “conservative estimates” due to lower than annual EF [ 39 ].…”