Herbívoros introducidos y el efecto Allee en plantas polinizadas por animales

  • Diego P. Vázquez Instituto Argentino de Investigaciones de las Zonas Áridas, Centro Regional de Investigaciones Científicas y Tecnológicas, CONICET, Mendoza, Argentina
Palabras clave: abundancia, efecto Allee, densodependencia, herbíviros introducidos, mutualismo, reproducción de plantas, polinización, especialización y generalización de polinizadores, dinámica poblacional


Las interacciones interespecíficas pueden ser moduladas por el contexto comunitario en el que ocurren. Este artículo estudia las interacciones planta-polinizador y su modulación por herbívoros introducidos mediante cambios en la densidad poblacional de las plantas. En primer lugar desarrollo un modelo matemático que relaciona la densidad poblacional de una planta polinizada por animales con la frecuencia de visitas por polinizadores, la polinización, la reproducción y la tasa per capita de crecimiento poblacional. Este modelo me permite investigar la influencia de varios parámetros relacionados con la polinización—incluyendo la abundancia relativa de la especie focal, la especialización de los polinizadores, la cantidad y la calidad de la polinización y la limitación por polen de la reproducción—sobre la relación entre la tasa per capita de crecimiento y la densidad poblacional. Luego utilizo este marco teórico para discutir dos estudios de caso que han evaluado los efectos mediados por la densidad de los herbívoros introducidos sobre la reproducción de las plantas. Este ejercicio me permite señalar algunas limitaciones de los estudios previos y sugerir direcciones para investigaciones futuras.


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