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Effects of local and landscape environmental variables on avifauna abundance in forest fragments of Atlantic Forest in southeastern Brazil
(Universidade Federal de São Carlos, 2018-06-06) Santos, Clarissa de Oliveira; Toppa, Rogério Hartung; https://lattes.cnpq.br/0673898572494729; Piratelli, Augusto João; https://lattes.cnpq.br/4747322084219058; https://lattes.cnpq.br/4625552320775478
Pristine Neotropical forests have been converted into agricultural lands. Shifts in the internal structure and external pressures on forest remnants affect bird assemblages that require specific resources for survival at different spatial scales. In this study, we verified the relative contribution of three spatial scales (local, immediate surroundings and landscape) on the abundance of birds in Atlantic forest fragments in south-eastern Brazil. We tested whether species that responded in a similar way to environmental variables are in the same foraging guild. We carried out this study through 44 fixed points in 18 fragments, in the buffer zone of a protected area. We sampled 15 environmental variables in three spatial scales; six site-specific, three at the immediate surrounds (buffer radius of 100m), and six at the landscape). We recorded 1724 individuals from 108 species between April 2017 and February 2018. We classified sampled species in 15 foraging groups. The unique fractions of local and landscape have affected bird abundance, but the exclusive immediate surroundings have not significantly influenced this variable. We have identified a pattern related to the effects of local scale only for insectivorous birds, but no pattern for the other foraging guilds linked to any other scales. Our study may support management practices in the studied sites, practices mainly improving the understory density and canopy height of the remaining patches of native forest.
Concretos refratários avançados contendo nano-óxidos produzidos pelo Método Pechini
(Universidade Federal de São Carlos, 2018-06-06) Alves Júnior, José Antonio; Baldo, João Baptista; https://lattes.cnpq.br/2410385643716370; Boschi, Anselmo Ortega; https://lattes.cnpq.br/3259846931278607; https://lattes.cnpq.br/7449451997419254
Recently there is a great effort to use the benefits of nanometric powders additions in the matrices of advanced refractory concretes of ; low (LC), ultra low (ULC) and no cement (NC) refractory concretes, in order to make their microstructures more resistant to corrosion and thermal shock damage. The common routes consist in the addition of nano-oxides of refractory phases of interest in the form of colloidal liquid or pre prepared powder. These during the firing of the concretes result in particles that are not really nanometric, but rather sub-micrometric or even micrometrics, which decreases their potential benefits. In this work, aiming the in situ development of nano oxide particles of Al, Mg and Cr, for better thermo mechanical properties, polymer resins produced by the Pechini Method, were added to advanced concretes (LC, ULC and NC) typical compositions, serving doubly as a kneading liquid for the refractory concretes and at the same time as a source of nano-oxides to the refractory concretes matrices. There is an important difference between this type of in situ development of nanoparticles and those derived from pre-prepared nanometric particles, considering that in the liquid resins the metals are in atomic condition, so that during the pyrolysis and oxidation of the same, the oxides will originate in nascent state, that is, in a truly nano scale, besides being highly reactive and more homogeneously distributed throughout the matrix. The results demonstrated that the inclusion of the liquid resins promoted a significant improvement in the thermomechanical properties of all the concretes when compared to those of no resin addition. Also for comparative grounds, it was prepared individually from each resin, its respective nano oxide powder. These were added to the mass of the refractory concretes in the same proportion of those obtained upon pyrolysis and oxidation of the resins. The results did not show any improvement in the thermomechanical properties comparatively to the in situ development of nano oxides by addition of the liquid resins.
Um estudo sobre plantadores de árvores e seu cuidado com as árvores em áreas urbanas públicas de Araras, SP, Brasil
(Universidade Federal de São Carlos, 2018-06-06) Ribeiro, André Lauand; Borges, Janice Rodrigues Placeres; https://lattes.cnpq.br/2373278362705384; https://lattes.cnpq.br/3877293039809446
The planter´s practice in public areas has not been special focus of academic studies in bibliography regarding urban arborization and greening. This dissertation proposes to narrow this academic gap, through a study about the contemporary tree-planter, as well as to discuss the role of man on caring for the local environment; considering two fundamental aspects: the rural origins of these tree planters and the caring aspect as vital to environment preservation and the return of direct contact of man with Nature in urban areas. The works were intitated with a search and initial observations in newspaper articles and visitation to the majority of the public spaces suit to planting in the municipality of Araras, SP, to come to this issue, that this phenomenon has been poorly studied, in face of a considerable number of planters observed in these areas. Later on, in loco visits, 121 areas of 350 were found (of 420 aproximattely in total) in which was observed practice of planting and caring by dwellers and 57 of them were identified as planters. Of these 57, 17 of them were chosen, in 7 areas, having planting and caring activity. In face of this, we opted to interview them, by means of a guide consisting of semi-structured interviews. The results point that all interviewees have ties with countryside/rural. Moreover, that caring for dwellers precedes maintenance. It emphasizes the tree planter´s role in taking care of Nature in the city. It also points to a renovation in the way of thinking about green areas. For example, inventory of tree planters also could be done (not just tree inventories), of those who engage in planting and taking care of them.