Actas de congresos
Linking geographic demography and niche theory to predict suitable habitats for Eschscholzia californica, an invasive plant of Central Chile
Fecha
2016Institución
Resumen
One important hypothesis, in relation to the abundance of species, across geographical distributions,
assumes that there are optimal sites (center of distribution) and sub-optimal sites (periphery) for survival
and reproduction. This pattern has been difficult to prove because environmental gradients not always
correlate with geographic distance to optimal places. These relationships could be more clearly observed
in the niche space (N-dimensional hypervolume), assuming that “central populations” are at the niche
centroid and they “peripheral populations” move off to the niche edges. We have studied population
dynamics and climatic niche of 17 populations of Eschscholzia californica, an invasive plant of Central
Chile. We evaluated the relationships between some demographic parameters: finite growth rate, plant
recruitment and abundance with the distance of each population to the niche centroid (using Mahalanobis
distance). We found a positive correlation between latitude (S) and distance to centroid of ecological niche;
the three demographic parameters declined significantly with increasing distance to the centroid. If the
climatic niche is conserved, we have a framework to make predictions about the success or failure of an
invasion of plants, since we could know if the invaded places are near or far from the optimal (centroid of
the niche). Thus, combining demography, niche theory and biogeography we have a tool to understand
invasive processes as well as to manageand anticipate the plant invasion.