Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change |
| |
Authors: | Kevin E. McCluney Jayne Belnap Scott L. Collins Angélica L. González Elizabeth M. Hagen J. Nathaniel Holland Burt P. Kotler Fernando T. Maestre Stanley D. Smith Blair O. Wolf |
| |
Affiliation: | 1. School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA;2. US Geological Survey, Southwest Biological Science Center, Moab, UT 84532, USA;3. Department of Biology, MSC03‐2020, University of New Mexico, Albuquerque, NM 87131, USA;4. Center for Advanced Studies in Ecology and Biodiversity (CASEB) & Departamento de Ecología, Pontificia Universidad Católica de Chile, Santiago, Chile;5. Institute of Ecology and Biodiversity (IEB), Casilla 653, Santiago, Chile;6. Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204, USA;7. Mitrani Department of Desert Ecology, Jacob Blaustein Institute for Desert Research, Ben‐Gurion University of Negev, Sede Boqer Campus, Midreshet Ben‐Gurion 84990, Israel;8. área de Biodiversidad y Conservación, Departamento de Biología y Geología, ESCET, Universidad Rey Juan Carlos, 28933 Móstoles, Spain;9. School of Life Sciences, University of Nevada, Las Vegas, NV 89154‐4004, USA |
| |
Abstract: | Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is expected to greatly alter the distribution of this critical resource. While previous studies have documented strong effects of global environmental change on species interactions in general, responses can vary from region to region. Dryland ecosystems occupy more than one‐third of the Earth's land mass, are greatly affected by changes in water availability, and are predicted to be hotspots of climate change. Thus, it is imperative to understand the effects of environmental change on these globally significant ecosystems. Here, we review studies of the responses of population‐level plant‐plant, plant‐herbivore, and predator‐prey interactions to changes in water availability in dryland environments in order to develop new hypotheses and predictions to guide future research. To help explain patterns of interaction outcomes, we developed a conceptual model that views interaction outcomes as shifting between (1) competition and facilitation (plant‐plant), (2) herbivory, neutralism, or mutualism (plant‐herbivore), or (3) neutralism and predation (predator‐prey), as water availability crosses physiological, behavioural, or population‐density thresholds. We link our conceptual model to hypothetical scenarios of current and future water availability to make testable predictions about the influence of changes in water availability on species interactions. We also examine potential implications of our conceptual model for the relative importance of top‐down effects and the linearity of patterns of change in trophic biomass with changes in water availability. Finally, we highlight key research needs and some possible broader impacts of our findings. Overall, we hope to stimulate and guide future research that links changes in water availability to patterns of species interactions and the dynamics of populations and communities in dryland ecosystems. |
| |
Keywords: | climate change precipitation drought moisture water availability species interactions competition mutualism herbivory predation top‐down trophic biomass |
|
|