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Item Green area and vegetation cover indexes for Parral city (Chile) using Photointerpretation and GISAutores: Mena, C.; Ormazabal, Y.; Morales, Y.; Santelices, R.; Gajardo, J.he importance of the green areas is increasing since they are an important factor in the health and welfare of urban population. Therefore, in Parral city, in Central Chile, it was quantified and analyzed the availability of green areas and vegetation cover, using aerial photographs scale 1: 10000 and Geographic Information Systems (GIS). In a first stage, urban street trees were quantified through a simple random sample of twenty-four units with field measurements combined with measurements on aerial photographs, from which it was obtained the surface provided. Subsequently, through the creation of GIS layers, the surface of existing green areas and available open spaces were obtained. In addition, through supervised digital classification, the surface covered by urban forestry in private spaces was calculated. Quantity indexes show that Parral city currently has 12.72 ha of green areas, equivalent to 4.82 m(2)/hab, which implies a green area frequency of 0.022 m(2)/m(2). These values could be improved, if the available open space are incorporated and thereby reach 12.06 m(2) per inhabitant. In relation with availability indexes it was established that the average of accessibility to a green area is 327.2 m. Moreover, assuming a buffer of 200 m around the green areas, it was determined that there are 5160 houses with the basic service (56.4%). By incorporating the available open spaces, these values decrease significantly obtaining an average of accessibility to a green area of 213.7 m and coverage of basic service of 79.2%. Finally, it was estimated that the existing vegetation within the urban blocks (urban forest in private spaces) represents an important resource 17.8 times larger than urban street trees, so it should be considered within the municipal plans and policies.Item Bayesian prediction of genetic parameters in Eucalyptus globulus CLONES UNDER WATER SUPPLY CONDITIONSAutores: Mora, F.; Rubilar, R.; Emhart, V.I.; Saavedra, J.A Bayesian analysis of genetic parameters for growth traits at twelve months after planting was carried out in twenty nine Eucalyptus globulus clones in southern Chile. Two different environmental conditions were considered: 1) Non-irrigation and; 2) Plants were irrigated with a localized irrigation system. The Bayesian approach was performed using Gibbs sampling algorithm in a clone-environment interaction model. Heritability values were high in the water supply condition (posterior mode: H2=0.41, 0.36 and 0.39 for height, diameter and sectional area, respectively), while in the environment without irrigation, the heritabilities were significantly lower, which was confirmed by the Bayesian credible intervals (95 % probability). The posterior mode of the genetic correlation between sites was positive and high for all traits (r=0.7, 0.65 and 0.8, for height, diameter and sectional area, respectively) and according to the credible interval, it was statistically different from zero, indicating a non-significant interaction.
