Distribuição natural de espécies arbóreas em áreas com diferentes níveis de antropização e relação com os atributos químicos do solo

With the emergence of areas degraded by human activities, the chemical soil properties and silvicultural characters became important in understanding the succession process of tree species and planning of landscape restoration. This study aimed to evaluate the distribution of tree species in areas with different levels of human disturbance, relating silvicultural aspects to the soil chemical properties and characterizing the type of vegetation, for integration of genetic conservation program in situ. The study was conducted in the area of Research and Extension Experimental Farm (FEPE) from UNESP, Ilha Solteira, in Selviria - MS. Through transect, 64 plots were marked 50 m equidistant with dimensions of 10 x 10 m, where: 29 plots were in an highly disturbed area (HDA), five in moderately disturbed area (MDA), 15 in lowly disturbed area (LDA), six in riparian stream of Vestia river (Riparian Forest) and nine in the legal reserve. Soil samples were collected at two depths (0.0 to 0.20 and 0.20 to 0.40 m) for the chemical analysis and the assessment of silvicultural characters, such as height, diameter at breast height (DBH) and shape. The study of the natural distribution of tree species and edaphic condition in the different evaluated areas showed that: the soil chemical properties associated with the level of human disturbance and conservation of the areas are influencing the natural occurrence, species diversity and development of the trees. Height, DBH and shape are good indicators to assess the growth of the tree community and relate them to soil chemical properties; LDA and legal reserve presented higher natural occurrence, number of individuals and number of species. In the riparian forest, basal area values, height, shape and chemical soil properties were higher. From the 97 species found, six have the potential to be used in a program of genetic conservation in situ. They are: Astronium fraxinifolium, Terminalia argentea, Curatella americana, Cupania vernalis, Qualea jundiahy and Andira cuyabensis.

Reinforcing and expanding the predictions of the disturbance vicariance hypothesis in Amazonian harlequin frogs: A molecular phylogenetic and climate envelope modelling approach

The disturbance vicariance hypothesis (DV) has been proposed to explain speciation in Amazonia, especially its edge regions, e. g. in eastern Guiana Shield harlequin frogs (Atelopus) which are suggested to have derived from a cool-adapted Andean ancestor. In concordance with DV predictions we studied that (i) these amphibians display a natural distribution gap in central Amazonia; (ii) east of this gap they constitute a monophyletic lineage which is nested within a pre-Andean/western clade; (iii) climate envelopes of Atelopus west and east of the distribution gap show some macroclimatic divergence due to a regional climate envelope shift; (iv) geographic distributions of climate envelopes of western and eastern Atelopus range into central Amazonia but with limited spatial overlap. We tested if presence and apparent absence data points of Atelopus were homogenously distributed with Ripley's K function. A molecular phylogeny (mitochondrial 16S rRNA gene) was reconstructed using Maximum Likelihood and Bayesian Inference to study if Guianan Atelopus constitute a clade nested within a larger genus phylogeny. We focused on climate envelope divergence and geographic distribution by computing climatic envelope models with MaxEnt based on macroscale bioclimatic parameters and testing them by using Schoener's index and modified Hellinger distance. We corroborated existing DV predictions and, for the first time, formulated new DV predictions aiming on species' climate envelope change. Our results suggest that cool-adapted Andean Atelopus ancestors had dispersed into the Amazon basin and further onto the eastern Guiana Shield where, under warm conditions, they were forced to change climate envelopes. © 2010 The Author(s).

Variabilidade genética de caracteres relacionados ao enraizamento de estacas de progênies e clones de guanandi (Calophyllum brasiliense Cambess

Pós-graduação em Ciência Florestal - FCA

Dependência espacial da estabilidade de agregados e matéria orgânica do solo em cambissolo sob cultivo de cana de açucar

The soil management system can modify the natural distribution of the soil attributes and, consequently, the variability of the soil aggregation and organic matter content. Thus, the aim of this work was to evaluate the aggregate stability and organic matter content spatial distribution on a Haplic Cambisol under sugar cane cultivation in the Southern Amazonas State, Brazil. A 70 x 70 m square mesh, with regular 10 meters intervals, was designed over the cultivation area, resulting in 64 sample points. Soil blocks with preserved structure were collected at 0.0-0.2 m depth in order to analyze the aggregate stability and organic matter content. The data were submitted to the descriptive and geostatistical analysis. The soil attributes presented a spatial dependence structure and the greater range was observed for the mean weighted diameter and aggregate class <1.00 mm. Also, there is a spatial relation among the mean geometric diameter, mean weighted diameter and aggregate classes (>2.00 and 2.00-1.00 mm).

Power-law distribution in a learning process: competition, learning and natural selection

In the present work, we propose a model for the statistical distribution of people versus number of steps acquired by them in a learning process, based on competition, learning and natural selection. We consider that learning ability is normally distributed. We found that the number of people versus step acquired by them in a learning process is given through a power law. As competition, learning and selection is also at the core of all economical and social systems, we consider that power-law scaling is a quantitative description of this process in social systems. This gives an alternative thinking in holistic properties of complex systems. (C) 2004 Elsevier B.V. All rights reserved.

Distribution of Xylella fastidiosa in citrus rootstocks and transmission of citrus variegated chlorosis between sweet orange plants through natural root grafts

To study translocation of Xylella fastidiosa to citrus rootstocks, budsticks from citrus variegated chlorosis (CVC)-affected cv. Pera sweet orange (Citrus sinenesis (L.) Osb.) were top grafted on 15 citrus rootstocks. Disease symptoms were conspicuous 3 months later on all 15 rootstocks tested. The presence of X. fastidiosa was confirmed by light microscopy, double-antibody sandwich enzyme-linked immunosorbent assays, and polymerase chain reaction in rootlets and main roots of CVC-symptomatic Pera sweet orange in 11 of the 15 rootstocks tested. These results suggest that bacterial translocation from the aerial plant parts to the root system occurs but is not essential for X. fastidiosa to induce symptoms in the aerial parts. Bacterial translocation to the roots was not correlated with CVC leaf-symptom severity in the Pera scion. To determine if CVC disease could be transmitted by natural root grafts, two matched seedlings of each of four sweet orange cultivars (Pera, Natal, Valencia, and Caipira) were transplanted into single pots. One seedling rootstock of each pair was inoculated by top grafting with a CVC-contaminated budstick while the other seedling rootstock was cut but not graft inoculated. Transmission of X. fastidiosa from an inoculated plant to a noninoculated plant sharing the same pot was observed in all four sweet orange cultivars tested. Transmission was confirmed by observation of natural roots grafts between the two plants, presence of X. fastidiosa in the root grafts, and disease development in the uninoculated plants. This is the first report of transmission of CVC disease through natural root grafts.

Stress distribution in ceramic restorations over natural tooth using finite element analysis. lithium disilicate x aluminum oxide material

Background: Data on stress distribution in tooth-restoration interface with different ceramic restorative materials are limited. The aim of this chapter was to assess the stress distribution in the interface of ceramic restorations with laminate veneer or full-coverage crown with two different materials (lithium dissilicate and densely sintered aluminum oxide) under different loading areas through finite element analysis. Materials and Methods: Six two-dimensional finite element models were fabricated with different restorations on natural tooth: laminate veneer (IPS Empress, IPS Empress Esthetic and Procera AllCeram) or full-coverage crown (IPS e.max Press and Procera AllCeram). Two different loading areas (L) (50N) were also determined: palatal surface at 45° in relation to the long axis of tooth (L1) and perpendicular to the incisal edge (L2). A model with higid natural tooth was used as control. von Mises equivalent stress (σ vM) and maximum principal stress (σ max) were obtained on Ansys software. Results: The presence of ceramic restoration increased σ vM and σ max in the adhesive interface, mainly for the aluminum oxide (Procera AllCeram system) restorations. The full-coverage crowns generated higher stress in the adhesive interface under L1 while the same result was observed for the laminate veneers under L2. Conclusions: Lithium dissilicate and densely sintered aluminum oxide restorations exhibit different behavior due to different mechanical properties and loading conditions. © 2011 Nova Science Publishers, Inc.

Lepidobatrachus asper Budgett,1899 (Amphibia: Anura: Ceratophryidae): New country record, distribution map and natural history notes

Lepidobatrachus asper is a large to medium frog known from the Chaco lowlands of Paraguay and Argentina. We provide the first species record for the Brazilian Chaco, which extends the species geographical distribution ca. 73 km northeast from Puerto Casado, Alto Paraguay Departament, Paraguay. We also provide a distribution map and information about the species habitat conditions and diet. The Brazilian Chaco is still poorly surveyed, and the rapid environmental degradation can lead to local extinctions of certain species. © 2013 Check List and Authors.

Diversity, natural history, and geographic distribution of snakes in the Caatinga, Northeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Advertisement call, colour variation, natural history, and geographic distribution of Proceratophrys caramaschii (Anura: Odontophrynidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Natural Host Relationships and Genetic Diversity of Rodent-Associated Hantaviruses in Southeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Survey for natural Neospora caninum infection in wild and captive birds

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bronze Bug Thaumastocoris Peregrinus Carpintero and Dellapé (Hemiptera: Thaumastocoridae) on Eucalyptus in Brazil and its Distribution

The bronze bug Thaumastocoris peregrinus Carpintero & Dellape (Hemiptera: Thaumastocoridae) was detected infesting Eucalyptus trees in Brazil in 2008, in the states of São Paulo, Rio Grande do Sul and Minas Gerais and in 2009 was found in the state of Espirito Santo, Mato Grosso do Sul, Rio de Janeiro and Parana. Details about geographical spread, means of introduction, impact in Eucalyptus plantations and natural enemies observed in the field are discussed.

Monitoramento e avaliação da borracha natural crua utilizando a técnica de análise térmica dinâmico-mecânica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Natural rubber latex used as drug delivery system in guided bone regeneration (GBR)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)