The Influence of Rainfall and Temperature on Radial Growth of Urban Trees Under the Impact of Steel Industry Pollution

The aim of this study was to analyze the growth rings and evaluate the effect of the urban environment on the growth of Terminalia catappa L. under intense industrial activity. At least two wood samples were obtained from each tree with an increment borer. The regions of Volta Redonda (Northwest and Southeast regions) and Resende (used as control) were established for the collection. The dendrochronological potential of T. catappa indicated sensitivity to precipitation and temperature in a more exposed urban and industrial steel pollution area because there were differences in growth when compared to an area less exposed to the same pollution. Thus, it was possible to conclude that this species has the potential to be used as a bioindicator of anthropogenic activities. In addition, the delimitation of the growth rings of the studied species contributes to the realization of future dendrochronological studies, expanding the understanding of the behavior of this species present in urban environments at different regional scales. This study reinforces the importance of rainfall and temperature in regulating radial growth in tropical forests

ANATOMICAL CHARACTERIZATION OF TENSION WOOD IN Hevea brasiliensis (Willd. ex A. Juss.) Mull. Arg.

ABSTRACT Tension wood is an important anatomical structure for its participation in the orientation of the trunk and the architecture of the branches as a function of structural reinforcement. However, its presence in large amounts significantly affects the technological properties of wood, just as in the rubber tree. Nevertheless, there is still demand for information about the origin, distribution and structural features in this species. Thus, this study aims to characterize the cellular structures in tension and opposite wood in Hevea brasiliensis (rubber tree), as well as its radial and longitudinal distribution. Discs at the base and the middle of the commercial logs were collected from three trees in a commercial plantation located in Tabapoã - SP. Tangential diameter of vessels, fiber length (gelatinous and non-gelatinous fibers), microfibril angle and proportionality of cellular elements (vessels, axial parenchyma, ray, gelatinous fibers and non-gelatinous fibers) were measured, and influence of gelatinous fiber presence in vessel diameter was observed. Gelatinous fibers were observed in the two types of wood and in the two trunk heights. Both types of wood were distinguished by gelatinous fiber length and the proportion of axial parenchyma. The tension wood in mid-trunk was the most different, with long gelatinous fibers and less abundant, larger vessel diameter and vessel proportion. Moreover, smaller vessel diameter was observed in the regions with a high proportion of gelatinous fibers, suggesting that the plant invests more support than in liquid transport