10.5061/DRYAD.Q41M844
Bimler, Malyon D.
University of Queensland
Stouffer, Daniel B.
University of Canterbury
Lai, Hao Ran
National University of Singapore
Yale-NUS College
Mayfield, Margaret M.
University of Queensland
Data from: Accurate predictions of coexistence in natural systems require
the inclusion of facilitative interactions and environmental dependency
Dryad
dataset
2019
Trachymene cyanopetala
Hypochaeris glabra
Waitzia acuminata
coexistence
Arctotheca calendula
niche
annual plants
fitness differences
Competitive outcomes
2019-05-24T00:00:00Z
2019-05-24T00:00:00Z
en
https://doi.org/10.1111/1365-2745.13030
97841 bytes
2
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
1. Coexistence between plant species is well known to depend on the
outcomes of species interactions within an environmental context. The
incorporation of environmental variation into empirical studies of
coexistence are rare, however, due to the complex experiments needed to do
so and the lack of feasible modelling approaches for determining how
environmental factors alter specific coexistence mechanisms. 2. In this
paper, we present a simple modelling framework for assessing how variation
in species interactions across environmental gradients impact on niche
overlap and fitness differences, two core determinants of coexistence. We
use a novel formulation of an annual plant population dynamics model that
allows for competitive and facilitative species interactions, and for
variation in the strength and direction of these interactions across
environmental gradients. Using this framework, we examine outcomes of
plant-plant interactions between four commonly co-occurring annual plant
species from Western Australian woodlands. We then determine how niche
overlap and fitness differences between these species vary across three
environmental gradients previously identified as important for structuring
diversity patterns in this system: soil phosphorus, shade and water. 3. We
found facilitation to be a wide-spread phenomenon and that interactions
between most species pairs shift between competitive and facilitative
across multiple environmental gradients. Environmental conditions also
altered the strength, direction and relative variation of both niche
overlap and fitness differences in non-linear and unpredictable ways.
Synthesis We provide a simple framework for incorporating environmental
heterogeneity into explorations of coexistence mechanisms. Our findings
highlight the importance of the environment in determining the outcome of
species interactions and the potential for pairwise coexistence between
species. The prevalence of facilitation in our system indicates a need to
improve current theoretical frameworks of coexistence to include
non-competitive interactions, and ways of translating these effects into
explicit predictions of coexistence. Our study also suggests a need for
further research into determining which factors result in consistent
responses of niche overlap and fitness differences to environmental
variation. Such information will improve our ability to predict outcomes
of coexistence, invasion events and responses of whole communities to
future environmental change.
Seed rate dataseed_rates.csvFecundity datafecundity_data.csv
SW Western Australia