Enfoques en el estudio de la reproducción sexual de las plantas en ambientes alterados: limitaciones y perspectivas

  • Marcelo A. Aizen Laboratorio Ecotono-CRUB, Universidad Nacional del Comahue, Bariloche, Río Negro, Argentina.
Palabras clave: disturbios antrópicos, ecología del paisaje, interacciones planta-polinizador, éxito reproductivo, enfoques, modelos conceptuales, polinización

Resumen

Las interacciones planta-polinizador son susceptibles a diferentes tipos de perturbaciones de origen antrópico. Aunque se supone que las distintas actividades humanas tienen impactos disruptivos o negativos sobre estas interacciones, el signo y la magnitud de los mismos dependen de una serie de variables ambientales y atributos biológicos cuya modificación puede tener efectos de signo contrario sobre distintos componentes de estos mutualismos. En consecuencia, el impacto de las perturbaciones antrópicas sobre la polinización y éxito reproductivo de las plantas no es fácilmente predecible a priori, dependiendo también de la intensidad, escala espacial y frecuencia del disturbio. El enfoque empleado mayormente en esta clase de estudios es de tipo comparativo y reduccionista. Esto resulta en una falta en la comprensión de los factores mediatos e inmediatos involucrados en la respuesta reproductiva de las plantas a las perturbaciones, y a interpretaciones erróneas, o a lo sumo incompletas, asociadas a repuestas curvilíneas y a una replicación reducida. En este trabajo reviso distintos tipos de limitaciones relacionados a este enfoque y propongo uno alternativo, que si bien es de naturaleza correlativa, permite una comprensión más mecanicista y la puesta a prueba de hipótesis de causalidad. El enfoque propuesto también permite asimilar, en forma más natural, al diseño de muestreo los patrones de perturbación que usualmente se encuentran en el campo, mejor reflejados por gradientes que por clases discretas. Esta aproximación también implica una mayor integración entre las áreas de la ecología reproductiva de plantas y la del paisaje.

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Publicado
2007-06-01
Sección
Sección Especial