Estructura poblacional de Tabebuia lepidophylla en el bosque de pinos sobre arenas cuarcíticas en Los Pretiles, Pinar del Río, Cuba /Population structure of Tabebuia lepidophylla in the pine forest on quartz sand of Los Pretiles, Pinar del Río, Cuba
Bibliographic record
Abstract
RESUMEN\nLas áreas caracterizadas por suelos derivados de rocas de cuarzo se encuentran entre las que más han favorecido el endemismo de la flora cubana. En el occidente cubano los suelos arenosos-cuarcíticos se encuentran restringidos a pocos afloramientos sobre los que se desarrollan bosques de pinos. Tabebuia lepidophylla es una especie endémica de esta formación vegetal, tanto en llanuras como en alturas de pizarra. Particularmente en los primeros, las condiciones impuestas por el sustrato pobre en nutrientes son críticas en el desarrollo de las poblaciones. En el presente estudio se caracterizó la estructura de la población de T. lepidophylla en el bosque de pinos sobre arenas cuarcíticas de la Reserva Ecológica Los Pretiles. Se establecieron 20 parcelas de 25 m2, 10 paralelas a la línea de costa y 10 hacia el interior del pinar, para evaluar la influencia de dicho gradiente en la estructura de la población. La población es estable con predominio de individuos en las dos primeras clases de altura, con frecuencias menores en las clases superiores. Dicha estructura constituye un indicador del óptimo estado de conservación de la población y de la capacidad de automantenerse. Los valores de densidad variaron entre zonas, con valores más altos en la zona lejana a la costa. El patrón de arreglo espacial resultó agregado, tanto a nivel poblacional como entre zonas. La distancia a la línea de costa condiciona e influye en la estructura de los individuos.\n\n\nPalabras claves: arreglo espacial, arenas blancas, densidad, gradiente, pinares\n\n\nABSTRACT\nThe areas characterized by soils derived from quartz rocks are among those that have contributed the most to the endemism of the Cuban flora. In western Cuba sandy-quartzite soils are restricted to few outcrops that support pine forests. Tabebuia lepidophylla is an endemic species of this vegetation, both in plains and heights slate. Particularly in the first, the conditions imposed by the nutrient-poor substrate are critical in the development of populations. In the present study, the population structure of T. lepidophylla in the pine forest on quartzite sands of the Ecological Reserve Los Pretiles is characterized. Twenty plots of 25 m2 were established, 10 parallel to the coastline and 10 were set into the pine forest, to assess the influence of the gradient in the structure of the population. The population is stable with a predominance of individuals in the first two height classes, with lower frequencies to the higher. This structure is an indicator of the optimal condition of the population and of its capacity to sustain itself. The density values varied between areas, with higher values far to the coast. The spatial distribution pattern of the population was clustered both at the population level and between areas. The distance to shore conditions and influences the structure of the individuals of the population.\n\nKeywords: spatial arrangement, white sands, density, gradient, pine forests\n\n\nRecibido: diciembre 2015 Aceptado: febrero 2016\n\nPublicado: 28 de abril de 2016
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".