Espécies invasoras: Conceitos, modelose atributos

The distribution of species in ecosystems is influenced by several biotic and abiotic factors, and physical barriers operate as filters to dispersion. The ancient processes of human migration and settlement, and the recent globalization trends are the main responsible factors for the transposition of geographic barriers by organisms and species introduction in regions outside their original distribution range. In order to designate introduced species, the adopted terminology may eventually lead to a lack of operational definitions, misleading the interpretation of paradigms concerning the invasion process. According to the literature, the criteria i) biogeographic, ii) population growth, and iii) spreading in the invaded region, should be taken into account as a manner to avoid subjective interpretations. Most of the presented models are inserted in the same paradigms to explain the status of the invasion process (arrival, establishment and invasion), although each model has its own concepts. Many authors consider both characteristics of the invader species and of the invaded environments to explain species success and establishment. The use of clear concepts, well established and non subjective concepts of introduced and invading species as well as its derivatives is crucial to unify the paradigms of the invasion process.

Desempenho operacional de semeadora-adubadora em diferentes manejos da cobertura e da velocidade

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Meio de cultura e tipo de explante no estabelecimento in vitro de espécies de maracujazeiro

Brazil is one of the main centers of genetic variability dispersion of the Passiflora genera. Its self incompatibility as well as disease incidence in its leaves and root system and, deforestation and monocultivation, promote loss of genetic material. Considering the risk of genetic erosion, the conservation of the variability in germplasm banks, which is of great interest in plant breeding, is necessary. Studies regarding the type of expiant and concentration of the culture media are necessary in order to determine protocols of establishment and in vitro conservation of passion-fruit germplasm. The objective of the present work was to evaluate the influence of the salt and nutrient concentration in the MS culture medium and types of expiants in the establishment and growth of the Passion fruit species: Passiflora giberti N. E.Brown, P. edulis Sims and P. laurifolia L. Each Passiflora species presented its own characteristics regarding in vitro development. The complete MS medium and nodal segments the second axilliary bud promoted better development of the genotypes studied.

Protección social en América Latina: cobertura, fuentes de financiamiento y organización de los sistemas

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Modelagem em escala regional da erosão relacionada com a evolução da cobertura do solo: Um estudo de caso no sudeste do Brasil

Accelerated soil erosion is, at present, one of the most widespread environmental problems in the world. Geographic Information Systems (GIS) have become an essential tool in soil erosion studies and consequently in the development of appropriate soil conservation strategies. The objective of this paper was to assess the degree of soil erosion associated with land cover dynamics through GIS analysis and to validate the modeling with indicators of soil erosion. Universal Soil Loss Equation (USLE) model, GIS technology and ground-truth dataset (erosion indicators) were employed to elaborate the soil loss maps for four dates at Sorocaba Municipality (SP, Brazil). It was verified that, although the predicted soil loss rate is normally small along the study area, such rate is significantly greater than the soil formation rate. This shows a non-sustainable situation of soil and land cover management. Unplanned urban expansion seems be the main driving force that acts in increasing the erosion risk/occurrence along the study area.

Cobertura da cultura da soja pela calda fungicida em função, de pontas de pulverização e volumes de aplicação

The goal of this research was to evaluate two tips of spraying nozzles (hollow cone nozzle and two flat fan nozzle annexed to a nozzle body DUO) and three spray volumes (100, 150 and 200 dm3 ha-1), whose application was for the control of the Asian soybean rust. An area of 288 m 2 was used, with a randomized blocks design in a factorial 2×3 with 4 repetitions, total of 24 experimental parcels of 12 m2. For the spraying with hydraulical nozzles a costal spray of constant pressure kept by C02 compressed with bar of 2 m was used. The analysis of the covering percentage was carried through by means of the use of hidro-sensible paper, that was placed in three position of the plant what it represents, in height, the third superior, average and inferior of the canopy. For both the third no interaction between the evaluated factors, was found and meither difference statistics between the spraying tips and the volumes. In absolute values the twin flat fan nozzle DUO presented minimum difference of covering in relation to the hollow cone nozzle, and for the spray volume of 200 dm3 ha -1 presented greater covering percentage.

Produção de agaricus blazei ss. Heinemann (A. brasiliensis) em função de diferentes camadas de cobertura e substratos de cultivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Desenvolvimento vegetativo de quatro espécies de grama irrigadas com efluente doméstico

This research aimed to compare the development of four grasses species irrigated by dripping with an effluent from a domestic wastewater station treatment in a small rural community, and supply water from Sabesp. For this purpose, an experiment was conducted in a greenhouse at the FCA/UNESP (Botucatu - SP) for 12 months in a completely randomized 4 × 3 factorial design, with four replications, totalizing 48 parcels. Grass species used in this experiment were: Santo Agostinho (Stenotaphrum secandatum (Walt.) Kuntze); Bermudas (Cynodum dactylon); Esmeralda (Zoysia japônica) and São Carlos (Axnopus sp). The treatments were: T1- Irrigation with re-use; T2- Irrigation with re-use + chemical fertilization and T3- Irrigation with supply water from Sabesp + chemical fertilization (control). Data were submitted to comparison of means by Tukey's test at 5 %. The results showed that nitrogen in the wastewater was enough for the good development of the grass species. However, its use caused higher potassium loss.

Estrategias para la universalización de la cobertura del sistema de pensiones

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Nitrogênio em cobertura e molibdênio via foliar em feijoeiro de inverno no sistema plantio direto II - Características agronômicas e produtividade

Nitrogen is the nutrient most uptaken by common bean plant, and molybdenum besides its importance to N fixation process, it is associated to N metabolism. The objective of this work was to evaluate, on common bean crop Pérola cultivar, the effect of N levels application at side dressing (0, 30, 60, 90 and 120 kg ha-1) as well as the leaf application of Mo (0, 80 and 160 g ha-1) at development stadium V3 or V4 under no tillage system. The experimental design was the randomized blocks with 30 treatments and 4 replications. The research was conducted in Selviria-MS on soil previously cropped with corn. The application of nitrogen levels at side dressing provided increasing on dry mass weight, number of pod and seeds per plant and grain yield, in the 2004; the Mo application at V3 or V4 stadia did not effect the production components and grain yield; as well as different doses of Mo depended on the N application at side dressing, in the 2004.

Regeneração natural de espécies da Mata Atlǎntica em sub-bosque de Eucalyptus saligna Smith. em uma antiga unidade de produção forestal no Parque das Neblinas, Bertioga, SP

This study aimed at characterizing the potential for natural regeneration of native vegetation in the under-story of an earlier Eucalyptus saligna Smith production stand. The study was carried out at the Parque das Neblinas, Bertioga municipality, SP, in a 45 ha third rotation stand; which had been abandoned 15 years ago for natural regeneration to occur. The sampling was done in 24 plots of 20 × 40 m. The sampled area was of 19,200 m2, with inventory made of 100% of the eucalyptus trees. All regeneration trees with a height ≥ 1.30 m and DBH ≥ 5.0 cm were measured, as well as adult individuals with DBH ≥ 5.0 cm; surveyed in two size classes. 1,417 individuals of E. saligna were measured, with a density of 738,02 individuals/ha and a basal area of 22.69 m2/ha. Among 2,763 natural regeneration individuals, 111 species belonged to 66 genera and 34 botanical families. The species represented 43.7% of the tree richness of neighboring native forest fragments. The total estimated density and the basal area were respectively 1,052.6 individuals/ha and 6.4 m2/ha of autochthonous trees with DBH ≥ 5.0 cm (Class 1); while for regeneration there were 3,864.58 individuals/ha, and 2.76 m2/ha of individuals with a height ≥ 1.30 m and DBH < 5.0 cm (Class 2). Shannon diversity (H') was 2.83 and 3.68, respectively, for Classes 1 and 2, and the corrected species richness for a 1000-individual sample (R1000) were 75.6 and 87.29 (Fisher's a index) for the same classes. The majority of the species (34.84%) was typical from the understory of wet tropical forest and had zoochoric fruit dispersal (67.57%). The results indicate that, under these conditions, a eucalyptus forest is able to provide adequate regeneration niches for native vegetation, and may represent a sink habitat for local populations.

Mutagenicidade de duas espécies do gěnero Alchornea avaliadas através de ensaios com Salmonella microssomo e teste do micronúcleo

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

Massa seca e composição bromatológica de quatro espécies de braquiárias semeadas na linha ou a lanço, em consórcio com milho no sistema plantio direto na palha

The objective of this research was to evaluate the dry mass yield and chemical composition of four Brachiaria species in different options for sowing, exclusively or in intercrop with corn crop, under a no-tillage system. The experiment was carried out during the growing seasons of 2006 at FEPE (FE/Unesp, Ilha Solteira Campus) located in Selvíria, Mato Grosso do Sul State, Brazil. The soil of the experimental area was classified as distroferric Red Latosol (Oxisol). The experimental design was in randomized blocks, in a factorial scheme (4 × 4), with five replications. The treatments consisted of four Brachiaria species (Brachiaria brizantha cv. Marandu, Brachiaria decumbens, Brachiaria ruziziensis and Mulato II grass) grown in rows and spread on total area, exclusively or intercropped simultaneously with corn crop sowing. The study evaluated the dry mass yield and total digestible nutrients, crude protein, ash, neutral detergent fiber, acid detergent fiber, hemicelluloses, cellulose and lignin content of forage. The spread on total area intercrop of forages with corn crop proved to be viable by presenting similar dry mass yield to exclusive sowing arrangements, conversely to what happened with intercrop in row of corn crop, which decreased such yield. Brachiaria ruziziensis showed superior chemical composition and the intercrops increased energy and crude protein contents, and decreased cell wall components.

Opciones de financiamiento para universalizar la cobertura del sistema de pensiones de Costa Rica

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Cobertura previsional en Chile: lecciones y desafíos del sistema de pensiones administrado por el sector privado

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