TY  - JOUR
A1  - Weiss, Lina
A1  - Schalow, Linda
A1  - Jeltsch, Florian
A1  - Geissler, Katja
T1  - Experimental evidence for root competition effects on community evenness in one of two phytometer species
JF  - Journal of plant ecology
N2  - Aims Plant-plant interactions, being positive or negative, are recognized to be key factors in structuring plant communities. However, it is thought that root competition may be less important than shoot competition due to greater size symmetry belowground. Because direct experimental tests on the importance of root competition are scarce, we aim at elucidating whether root competition may have direct or indirect effects on community structure. Indirect effects may occur by altering the overall size asymmetry of competition through root-shoot competitive interactions. Methods We used a phytometer approach to examine the effects of root, shoot and total competition intensity and importance on evenness of experimental plant communities. Thereby two different phytometer species, Festuca brevipila and Dianthus carthusianorum, were grown in small communities of six grassland species over three levels of light and water availability, interacting with neighbouring shoots, roots, both or not at all. Important Findings We found variation in community evenness to be best explained if root and shoot (but not total) competition were considered. However, the effects were species specific: in Dianthus communities increasing root competition increased plant community evenness, while in Festuca communities shoot competition was the driving force of this evenness response. Competition intensities were influenced by environmental conditions in Dianthus, but not in Festuca phytometer plants. While we found no evidence for root-shoot interactions for neither phytometer species root competition in Dianthus communities led to increased allocation to shoots, thereby increasing the potential ability to perform in size-asymmetric competition for light. Our experiment demonstrates the potential role of root competition in structuring plant communities.
KW  - plant-plant interactions
KW  - root and shoot competition
KW  - intensity vs
KW  - importance
KW  - experimental plant communities
KW  - asymmetry of competition
Y1  - 2018
U6  - https://doi.org/10.1093/jpe/rty021
SN  - 1752-9921
SN  - 1752-993X
VL  - 12
IS  - 2
SP  - 281
EP  - 291
PB  - Oxford Univ. Press
CY  - Oxford
ER  -