Saguaro recruitment data obtained by inverse-growth modelling
Larios, Eugenio; Felix-Burruel, Ricardo Efren; Gonzalez, Edgar J.; Burquez, Alberto (2021), Saguaro recruitment data obtained by inverse-growth modelling, Dryad, Dataset, https://doi.org/10.5061/dryad.rn8pk0p99
Each year, an individual mature large saguaro cactus produces about one million seeds in attractive juicy fruits that lure seed predators and seed dispersers in a three-month feast. From the million seeds produced, however, only a few will persist into mature saguaros. A century of research on saguaro population dynamics has led to the conclusion that saguaro recruitment is an episodic event that depends on the convergence of suitable conditions for survival during the critical early stages. Because most data have been collected in Arizona, particularly in the surroundings of Tucson, most research has relied on a limited amount of environmental variation. In this study, we upscaled this knowledge on saguaro recruitment to a regional scale with a new method that used the inverse-growth modeling of 1,487 saguaros belonging to 13 populations in a latitudinal gradient ranging from arid desert to tropical thornscrub forest in Sonora, Mexico. Using generalized linear and additive mixed models, we created two 110-year-long saguaro recruitment curves: one driven only by previous size, and the second driven by size, drought, and soil structure. We found evidence that saguaro recruitment is indeed episodic with periodicities of 20–30 years possibly related to strong El Niño Southern Oscillation events. Our results suggest that saguaros rely on multidecadal periodic pulses of good beneficial years to incorporate new individuals into their populations. Inverse-growth modelling can be used in a wide variety of plant species to study their recruitment dynamics.
Size and SizeNext variables are related to the transition from time at t (Size) to time at t+1 (SizeNext). They are saguaro heights of the main stem measured in cm.
Sites are abbreviated in the dataset while not in the manuscript.
SWS is the abbreviation of "soil water content at saturation" and is a proportion per individual per site.
PDSI_Anual is the mean monthly "Palmer drought severity index" extracted for each site and each year.
Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, Gobierno de México, Award: ES008
UNAM, Award: IN213814
UNAM, Award: IN213814