Embed Size (px)
Citation preview
Travel & Training grant provided by the BES
The Hydroniche project is funded by the DFG Priority Program 1374
Effect of water fluctuation on the composition and diversity Effect of water fluctuation on the composition and diversity of terrestrial plant communities – of terrestrial plant communities – a reviewa reviewFrederic Clement, Carsten F. Dormann. [email protected] Department of Biometry and Environmental System Analysis, University of Freiburg, Germany
Hours
Days
Seasons
Years
Observational evidence
Experimental manipulation
TEMPORAL VARIABILITY SCALE
Day
Season
Year
Richness - Diversity Mesic grassland
DiversityNeo tropical wet forest
Diversity - Composition Limestone
Coexistence mechanismsMesic prairie
Diversity - Composition Limestone
Diversity - Composition Semiarid prairie
Composition Semiarid understorey
CompositionMulti-system
Composition Mesic pineland
CompositionMediterranean systems
Diversity - CompositionWetland
(Hours)
Wat
er A
vaila
bilit
y
Mesic
Dry
Wet
Perspectives
Extract per scale variation with frequencydomain analysis
(eg. wavelet decomposition)
No scale comparisons and use of restricted tools to quantify the fluctuations
Current limitations
Experiments are logistically expensiveNo experiments on forest ?
New technologies are reducing the cost
Limited quantification of coexistence mechanisms
With increased heterogeneity:●composition shift towards more xeric systems
●diversity increase in experiments but decrease in most of the natural observation.
Response depends on scale and system
Preliminary conclusions
What to expect from water fluctuation ?
Composition
Hierarchy of response to resource pulse.Fluctuation as a dimension of the plant's niche→ Shift to a more adapted community
Diversity
Potential stabilizing or equalizing effect on competition
→ Enable coexistence and increase richness
Moisture gradient
Growth
Time
Germination
Moisture gradient
WetXeric
Fluctuation
Recent evidences suggest that additionally to the average water availability, the temporal distribution of water has significant impact the ecology of plant communities.
At the same time, temporal distribution is expected to increase under present Climate Change scenarios. This projection strengthen the necessity to integrate temporal variability for insight into future
The present work is intended to report and to synthesize currently available evidence by the mean of systematical review of the literature.
Introduction
