6 research outputs found

    Distribution patterns of endemic flora to define hotspots on Hispaniola

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    Nineteen areas on the island of Hispaniola (Haiti and the Dominican Republic) were studied with the aim of determining the distribution pattern of the endemic flora in these areas, and their variability with altitude. The main concentration of endemic species occurs in mountains with a medium altitude and in certain mountain sites (palaeo-islands), which coincide with hotspots; a lower number of endemics are found in low-lying areas (coldspots), due to the degradation of their habitats. A total of 1,582 endemic species were studied and were distributed in 19 areas. The whole island is of outstanding interest for its richness in endemics; it has 2,050 endemic species, representing 34.16% of its total flora. The territory in the study is home to 1,284 genera of which 31 are endemic to the island, including monotypical genera such as Tortuella abietifolia Urb. & Ekman, and endemic genera such as Hottea, containing seven endemic species. The sites with the highest rate of endemics are area A16 in the central range with a total of 440 endemic species, of which 278 are exclusive to the territory; and the Sierra de Bahoruco, la Selle, La Hotte and Tibur on in area A12, where we found 699 plants of which 482 are endemic and exclusive to the area; and A13 with 173 and 129 respectively. This work highlights the exceptional floristic diversity in endemic species and genera and analyses their distribution patterns as a tool for conservation in this area of the world, whose high endemicity rate makes it one of the most significant hotspots in the Caribbean

    Expansion of the Juniperus Genus due to Anthropic Activity

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    This work contains a study of Juniperus forests in the southern Iberian Peninsula and aims to determine their floristic composition and their biogeographical, ecological and bioclimatological distribution. The analysis of Juniperus formations revealed a series of different plant communities. The presence of endemic companions in these plant communities justifies the study of these islands: Echinospartum ibericum Rivas Mart., Sánchez Mata & Sancho, Adenocarpus argyrophyllus (Rivas Goday) Caball., Digitalis purpurea L. subsp. mariana (Boiss.) Rivas Goday, Sideritis lacaitae Font Quer, Coincya longirostra (Boiss) Greuter & Burdet, Cytisus scoparius (L.) Link subsp. bourgaei (Boiss.) Riv.-Mart., Cytisus striatus (Hill) Rothm. subsp. eriocarpus (autor), Genista polyanthos R. Roem. Ex Willk., Dianthus crassipes R. de Roemer, Dianthus lusitanus Brot. Digitalis thapsi L., Digitalis purpurea L. subsp. Heywoodii P. Silva & M. Silva, subsp. mariana (Boiss) Rivas Goday, Securinega tinctoria (L.) Rothm., Lavandula stoechas L. subsp. luisieri (Rozeira) Rozeira, lavandula stoechas subsp. sampaiana Rozeira, Genista hirsuta Vahl, Thymus mastichina (L.) L., Thymus grantensis Boiss. subps. micranthus (Willk.) O. Boòs & Vigo, Thymus zygis Loefl ex L. subsp. gracillis (Boiss.) Boiss., Antirrhinum graniticum Roth. subsp. onubensis (Fernández Casas) Valdés. The territories in the study are of community interest (SCI) due to the presence of habitats such as Habitat 8220, which includes the plant associations Digitali thapsi-Dianthetum lusitani Rivas-Martínez ex Fuente 1986, Jasiono marianae-Dianthetum lusitani Rivas Goday (1955) 1964, Coincyo longirostraae-Dianthetum lusitani Melendo in Cano, Melendo & F. Valle 1997, and is the motive for the need to conserve these areas. However the dominant species in these environments is Juniperus oxycedrus L. subsp. lagunae (Pau ex C. Vicioso) Rivas Mart., and all the other –mainly endemic– species are located within its vicinity. These zones can thus be classified as hotspots with particular interest for conservation. Areas dominated by Juniperus are currently becoming more widespread due to the greater prevalence of rock beds, which increase every year in response to deforestation and forest fires. This phenomenon leads to the extension of edaphoxerophilous zones and a decrease in climatophilous zones, and creates more potential areas that can potentially act as a refuge for endemic species

    New Method for Increasing Sustainable Agricultural Yield

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    The main objective of this study is to look for a new method, to obtain the maximum production, and the minimum economic and environmental cost. Scientific advances in bioclimatology have brought a greater understanding of the functioning of plant individuals, populations and communities, and the study and interpretation of bioclimatic indices reveals the close relationship between the values of these indices and crop yields. In cases where insufficient meteorological data are available to allow the various formulas to be applied, thermoclimatic and ombroclimatic bioindicators must be used, some of which have been collected by us in previous works. This paper contains a bioclimatic study of the southern Iberian Peninsula in relation to the main olive varieties grown in these territories. We establish the values of some key indices for cultivation: continentality index (Ic), which determines the annual thermal range and allows us to establish the period of vegetative activity (PAV); the ombrothermic index (Io), which measures the ombrotype in the different sites; and the thermicity and compensated thermicity index, which denote the thermotype in the territory (It/Itc). In the relationship between the value of the bioclimatic indices and olive production, good fits are obtained in the regression analysis with R2> 0.90, and is very positive influence of the different parameters used. In conclusion the greatest influence on the production of Ic is between 18.5-19.5, Io 3.5-4.5 and It / Itc 320-350. This allows to obtain areas of maximum production with a lower economic cost

    Indicative value of the dominant plant species for a rapid evaluation of the nutritional value of soils

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    A study was conducted on 14 grassland communities located in the south of the Iberian Peninsula and their edaphology, which is identified as specific plant associations. The edaphic study of each association allows a rapid evaluation of the nutrient content in the soil without the need for laboratory edaphic analysis. For each phytosociological relevé and soil, samplings were carried out. The field data were subjected to various statistical analysis—canonical correspondence analysis (CCA), Bayesian networks, and decision trees—to establish nutrient content. When the abundance value of the species is 9 in the Van der Maarel scale, there is an increase in the values of several soil parameters. In the case of Hordeum leporinum, when the Van der Maarel index is 9, the Kc (exchangeable potassium in cmol/kg) undergoes the greatest variation, to a value of up to 0.729 cmol/kg. The application of the decision tree to this species reveals that the soil attributes with the greatest influence in the classification are conductivity, %_si (silt texture), pH, and pF 15 atm (pressure at 15 atmospheres (water retention capacity) in %). Indeed, this interlaced edaphic and phytosociological study provides us with a high-value tool to obtain quick information on the content of nutrients in the soil.info:eu-repo/semantics/publishedVersio

    Indicative Value of the Dominant Plant Species for a Rapid Evaluation of the Nutritional Value of Soils

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    A study was conducted on 14 grassland communities located in the south of the Iberian Peninsula and their edaphology, which is identified as specific plant associations. The edaphic study of each association allows a rapid evaluation of the nutrient content in the soil without the need for laboratory edaphic analysis. For each phytosociological relevé and soil, samplings were carried out. The field data were subjected to various statistical analysis—canonical correspondence analysis (CCA), Bayesian networks, and decision trees—to establish nutrient content. When the abundance value of the species is 9 in the Van der Maarel scale, there is an increase in the values of several soil parameters. In the case of Hordeum leporinum, when the Van der Maarel index is 9, the Kc (exchangeable potassium in cmol/kg) undergoes the greatest variation, to a value of up to 0.729 cmol/kg. The application of the decision tree to this species reveals that the soil attributes with the greatest influence in the classification are conductivity, %_si (silt texture), pH, and pF 15 atm (pressure at 15 atmospheres (water retention capacity) in %). Indeed, this interlaced edaphic and phytosociological study provides us with a high-value tool to obtain quick information on the content of nutrients in the soil.Depto. de Didáctica de las Ciencias Experimentales , Sociales y MatemáticasFac. de EducaciónTRUEpu

    La formación del educador deportivo en baloncesto : bloque específico nivel I

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    Esta obra tiene un segundo volumen con el mismo título, y con el subtítulo: Bloque específico nivel IILa formación de los entrenadores de baloncesto ha experimentado una evolución constante en los últimos años debido a diversas causas, entre las que destaca el cambio legislativo debido a la ley del deporte. Dicha ley regula el proceso de formación de los técnicos y amplía considerablemente el volumen de horas de duración, así como las exigencias para el alumnado. Esta obra recoge tanto conocimiento científico, como sentido práctico. Así, es recomendable no solo a quienes participen en cursos de formación, sino a todos los que se sienten atraídos por la tarea de enseñar baloncesto.AndalucíaBiblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín 5 -3 Planta; 28014 Madrid; Tel. +34917748000; [email protected]
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