Se estudiaron las condiciones fisionómicas, ecológicas y fitosociológicas de las fitocenosis observadas en los dos tipos de pluvisilvas sobre ofiolitas presentes en el Parque Nacional Alejandro de Humboldt; ellas son las más desarrolladas, extensas, conservadas y típicas del archipiélago cubano. Algunas tienen tres estratos arbóreos y alcanzan hasta 45 m de altura. Se presentan desde cerca del nivel del mar hasta los 900 m, con precipitaciones de alrededor de 2000 mm a 3600 mm. Se describen por primera vez dos alianzas, cuatro asociaciones y siete subasociaciones, lo que fortalece los valores del parque como Patrimonio de la Humanidad.
This study attempts to analyze the relationship between two key psychological variables associated with performance in sports – Self-Determined Motivation and Competitive Anxiety – through Bayesian Networks (BN) analysis. We analyzed 674 university students that are athletes from 44 universities that competed at the University Games in Mexico, with an average age of 21 years (SD = 2.07) and with a mean of 8.61 years’ (SD = 5.15) experience in sports. Methods: Regarding the data analysis, firstly, classification using the CHAID algorithm was carried out to determine the dependence links between variables; Secondly, a BN was developed to reduce the uncertainty in the relationships between the two key psychological variables. The validation of the BN revealed AUC values ranging from 0.5 to 0.92. Subsequently, various instantiations were performed with hypothetical values applied to the “bottom” variables. Results showed two probability trees that have extrinsic motivation and amotivation at the top, while the anxiety/activation due to worries about performance was at the bottom of the probabilities. The instantiations carried out support the existence of these probabilistic relationships, demonstrating their scarce influence on anxiety about competition generated by the intrinsic motivation, and the complex probabilistic effect of introjected and identified regulation regarding the appearance of anxiety due to worry about performance.
Los líquenes epífitos que crecen en los árboles de la pluvisilva montana de la Gran Piedra (Cuba) muestran claramente una distribución vertical sobre los troncos. Se han establecido nueve cuadrados de 625 m 2 de cinco forófitos diferentes. Cada árbol se dividió en cuatro zonas desde la base hasta las ramas más altas. Se han encontrado 115 especies de las que hay 50 nuevas para Cuba. Las especies de biotipo crustáceo con reproducción sexual son las más frecuentes a lo largo de todo el árbol. La familia Thelotremataceae domina en la base de los troncos (zona I) mientras que Graphidaceae y Parmeliaceae son más abundantes en las ramas más altas. Las zonas II, III y IV poseen la mayor diversidad de especies.
Reyes, O.J. & Acosta Cantillo, F. Semi-deciduous forests sintaxa from Sierra Maestra, Eastern Cuba. Lazaroa 35: 37-53 (2014).Five associations from two classis, three orders and four alliances are described in low Sierra Maestra semideciduous forests. Two of microphill semideciduous forests are in soils from calcareous rocks, while the three from mesophill semideciduos forests grow up in soils developed over volcanic rocks from El Cobre group. In this work we have used the Zurich -Montpellier school methodology, which is easily used in the Cuban archipelago.
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