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Los efectos de escala y el impacto humano en los gradientes de riqueza de especies de elevación
D Nogués-Bravo1, M B Araújo, T Romdal
1Department of Biodiversity and Evolutionary Biology, National Museum of Natural Sciences, CSIC, C/ José Gutiérrez Abascal, 2, 28006 Madrid, Spain. davidnogues@mncn.csic.es
Nature
|May 10, 2008
Resumen
Los patrones de riqueza de especies dependen de la escala del análisis. La variación de la escala de estudio puede crear patrones conflictivos, lo que dificulta la búsqueda de gradientes universales de biodiversidad.
Área de la Ciencia:
- Ecología Ecología Ecología.
- Biodiversidad Ciencia La ciencia de la biodiversidad.
- La biogeografía es la biogeografía.
Sus antecedentes:
- Los gradientes ambientales, en particular los de altitud, son cruciales para comprender los patrones de riqueza de especies.
- Las investigaciones anteriores asumieron patrones universales, pero el consenso sigue siendo difícil de alcanzar.
- Los gradientes altitudinales son modelos clave para probar las hipótesis de diversidad.
Objetivo del estudio:
- Para investigar cómo la escala de análisis afecta a los patrones de riqueza de especies observadas a lo largo de gradientes altitudinales.
- Para determinar si los efectos de escala pueden explicar los patrones de diversidad contradictorios informados en la literatura.
- Evaluar el impacto de la escala en el apoyo a diferentes hipótesis de diversidad.
Principales métodos:
- Nuevo muestreo de un gran conjunto de datos (400.000 registros, 3.046 especies) de los gradientes florísticos pirenaicos.
- Analizar patrones de riqueza de especies en diferentes escalas ajustando el tamaño del grano y la extensión del gradiente.
- Evaluación estadística del apoyo a las hipótesis de diversidad competitivas basadas en patrones dependientes de la escala.
Principales resultados:
- Los patrones de riqueza de especies pasaron de ser en forma de joroba a ser monótonos a medida que disminuía la escala de análisis.
- Los efectos de escala por sí solos generaron patrones contradictorios previamente reportados en la literatura.
- Los efectos de escala influyeron significativamente en el apoyo estadístico de varias hipótesis de diversidad.
Conclusiones:
- Los patrones de riqueza de especies observadas son altamente dependientes de la escala.
- Los efectos de escala pueden explicar discrepancias en estudios previos y dificultar la identificación de gradientes universales de diversidad.
- Los impactos humanos en los ecosistemas montañosos pueden exacerbar los efectos de escala, lo que complica la investigación de la biodiversidad.
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