Potential changes in the distribution of Carnegiea gigantea under future scenarios

Abstract

Over the last decades several studies have identified that the directional changes in climate induced by anthropogenic emissions of greenhouse gases are affecting the ecology of desert ecosystems. In the Southwest United States, the impacts of climate change to plant abundance and distribution have already been reported, including in the Sonoran Desert ecosystem, home of the iconic Saguaro (Carnegiea gigantea). Hence, there is an urgent need to assess the potential impacts of climate change on the saguaro. The goals of this study are to provide a map of actual habitat suitability (1), describe the relationships between abiotic predictors and the saguaro distribution at regional extents (2), and describe the potential effect of climate change on the spatial distribution of the saguaro (3). Species Distribution Modeling (SDM) was used to investigate the relationships between abiotic variables and the Saguaro distribution. SDMs were calibrated using presence records, 2,000 randomly-generated pseudo absences, and ten abiotic variables. Of these, annual precipitation and max temperature of the warmest month was found to have the greatest relative influence on saguaro distribution. SDMs indicated that 6.9% and 8.1% of the current suitable habitat is predicted to be lost by 2050 and 2070, respectively. Therefore, predicted changes in climate may result in a substantial contraction of the suitable habitat for saguaro over the next century. By identifying the drivers of saguaro distribution and assessing potential changes in habitat suitability due to climate change, this study will help practitioners to design more comprehensive strategies to conserve the saguaro in the face of climate change.

Nonlinear modeling of saguaro growth rates reveals the importance of temperature for size‐dependent growth

“…In this sense, our results closely agree with those of Albuquerque et al. () showing that annual precipitation and maximum temperature in the warmest month are the major factors influencing saguaro distribution.…”

“…As highlighted by Albuquerque et al. (), climate change will likely modify the distribution of emblematic species like the saguaro cactus. The IPCC climate models (IPCC, ) project a 3° to 5°C increase in average annual temperature and increased interannual precipitation variability in the next 100 years for the Sonoran Desert.…”

Regionalización biogeográfica y evolución biótica de México: encrucijada de la biodiversidad del Nuevo Mundo

“…La provincia de Sonora se halla amenazada por la irrigación, los ranchos ganaderos, la extracción de leña, la explotación de la vida silvestre, la caza excesiva y el uso intensivo con fines turísticos (Dinerstein et al, 1995). Un análisis reciente de modelado de nicho ecológico de Carnegeia gigantea a escenarios de incremento de temperatura (Albuquerque et al, 2018) estimó que la distribución geográfica de este cacto podría contraerse de continuar las tendencias actuales de cambio climático. En esta provincia se incluyen varias áreas naturales protegidas (Conanp, 2018):…”

Projected climate change threatens significant range contraction of Cochemiea halei (Cactaceae), an island endemic, serpentine‐adapted plant species at risk of extinction

“…In particular, climate projections under all representative concentration pathways (RCPs) of atmospheric "greenhouse gasses" and particulates show increased mean temperatures ranging from 1.5°C to 4.5°C globally and increased aridification of existing deserts due to larger areas subject to lower amounts of annual rainfall (Collins et al, 2013). Specifically concerning Cactaceae, prior to 2019, there were very few studies of habitat suitability and the potential effects of climate change on habitat suitability or distribution (Albuquerque et al, 2018;Butler et al, 2012;Martorell & Peters, 2005;Téllez-Valdés & Dávila-Aranda, 2003).…”

“…Although cacti are adapted to arid conditions, prior studies have shown that they are nevertheless vulnerable to projected changes in both temperature and precipitation under climate change scenarios (Albuquerque et al, 2018;Butler et al, 2012;Martorell & Peters, 2005;Téllez-Valdés & Dávila-Aranda, 2003). The effect of climate change on the future suitable habitat of C. halei is unknown.…”