Resource fluctuations and niche separation in plant communities: Can land-use effects on soil moisture explain observed patterns in plant diversity?

 

Scientific investigators:

Prof. Dr. Carsten F. Dormann

(University of Freiburg)

JunProf. Dr. Anke Hildebrandt

(University of Jena)

 

Goal

Evaluate the importance of fluctuations in soil water content for plant species diversity

 

Hypotheses

H1.    Plant species trade-off in their ability to tolerate drought and water logging (as proposed by Silvertown et al. (1999).

H2.    Fluctuating soil moisture, not adaptation to local conditions, is driving diversity.
Fluctuations shift optimal conditions between species, allowing coexistence (“storage effect”) and thus higher diversity.

 

Methods

Statistical analysis of the trade-off idea using vegetation and soil moisture data from the Biodiversity Exploratories (grassland and forest) and randomization test-based analysis.
Additionally, we shall carry out a mesocosm experiment as a proof of principle: Manipulations of water level fluctuations will lead to differences in composition and diversity.