TY  - JOUR
A1  - Seifan, Merav
A1  - Seifan, Tal
A1  - Schiffers, Katja
A1  - Jeltsch, Florian
A1  - Tielboerger, Katja
T1  - Beyond the competition-colonization trade-off - linking multiple trait response to disturbance characteristics
JF  - The American naturalist : a bi-monthly journal devoted to the advancement and correlation of the biological sciences
N2  - Disturbances' role in shaping communities is well documented but highly disputed. We suggest replacing the overused two-trait trade-off approach with a functional group scheme, constructed from combinations of four key traits that represent four classes of species' responses to disturbances. Using model results and field observations from sites affected by two highly different disturbances, we demonstrated that popular dichotomous trade-offs are not sufficient to explain community dynamics, even if some emerge under certain conditions. Without disturbances, competition was only sufficient to predict species survival but not relative success, which required some escape mechanism (e.g., long-term dormancy). With highly predictable and large-scale disturbances, successful species showed a combination of high individual tolerance to disturbance and, more surprisingly, high competitive ability. When disturbances were less predictable, high individual tolerance and long-term seed dormancy were favored, due to higher environmental uncertainty. Our study demonstrates that theories relying on a small number of predefined trade-offs among traits (e.g., competition-colonization trade-off) may lead to unrealistic results. We suggest that the understanding of disturbance-community relationships can be significantly improved by employing sets of relevant trait assemblies instead of the currently common approach in which trade-offs are assumed in advance.
KW  - competition resistance trade-off
KW  - functional types
KW  - intermediate disturbance hypothesis
KW  - plant communities
KW  - species assemblies
Y1  - 2013
U6  - https://doi.org/10.1086/668844
SN  - 0003-0147
VL  - 181
IS  - 2
SP  - 151
EP  - 160
PB  - Univ. of Chicago Press
CY  - Chicago
ER  - 
TY  - JOUR
A1  - Seifan, Merav
A1  - Seifan, Tal
A1  - Jeltsch, Florian
A1  - Tielboerger, Katja
T1  - Combined disturbances and the role of their spatial and temporal properties in shaping community structure
JF  - Perspectives in plant ecology, evolution and systematics
N2  - Disturbances are characteristic for many ecosystems. However, we still lack generalizations concerning their role in shaping communities, particularly when disturbances co-occur. To study such effects, we used a novel modeling approach that is unrestricted by a priori tradeoffs among specific plant traits, except for those generated by allocation principles. Thus, trait combinations were emergent properties associated with biotic and abiotic constraints. Specifically, we asked which traits dominate under specific disturbance regimes, whether single and combined disturbance regimes promote similar trait tradeoffs and how complex disturbance regimes affect species richness and functional diversity. Overall, disturbances' temporal properties governed the outcome of combined disturbances and were a stronger assortative force than spatial disturbance properties: low temporal predictability decreased seed-dispersability and dormancy, but increased competitive ability and disturbance tolerance. Evidence for tradeoffs between different colonization modes and between dormancy and disturbance tolerance were found, while surprisingly, the widely accepted colonization-competition tradeoff was not generated. Diversity was highest at intermediate disturbance intensity, but decreased monotonically with increasing unpredictability. In accordance with our results, future models should avoid restrictive assumptions about tradeoffs to generate robust and more general predictions about the role of disturbances for community dynamics.
KW  - Intermediate disturbance hypothesis
KW  - Coexistence
KW  - Environmental heterogeneity
KW  - Competition-colonization
KW  - Plant community
KW  - Individual-based model
Y1  - 2012
U6  - https://doi.org/10.1016/j.ppees.2011.11.003
SN  - 1433-8319
VL  - 14
IS  - 3
SP  - 217
EP  - 229
PB  - Elsevier
CY  - Jena
ER  -