Chara can outcompete Myriophyllum under low phosphorus supply |
| |
| Authors: | Doreen Richter Elisabeth M Gross |
| |
| Institution: | 1. Limnological Institute, University of Konstanz, Mainaustra?e 252, 78464, Konstanz, Germany
2. Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) UMR 7360 CNRS, Université de Lorraine, Campus Bridoux, 8, Rue du Général Delestraint, 57070, Metz, France
|
| |
| Abstract: | In the course of re-oligotrophication in Lower Lake Constance, Germany, the tall-growing angiosperm Myriophyllum spicatum has been almost replaced by dense and lower-growing charophytes. We hypothesise that Chara globularis negatively affects the performance of M. spicatum due to density competition and nutrient interference. Intra- and interspecific competition was assessed using a response surface experimental design with different densities of both species in mono and mixed stands in an outdoor mesocosm experiment. After 8 weeks, we measured the growth and various functional traits of both species, including stoichiometry, ash-free dry mass and dry-matter content, and for M. spicatum, additionally chlorophyll content, leaf-mass fraction, formation of autofragments, and root/shoot ratio. With increasing density, C. globularis reduced the growth of M. spicatum much more strongly than that of conspecifics. Increasing density of C. globularis led to a lower chlorophyll a to b ratio and lower nitrogen content based on ash-free dry mass in M. spicatum as well as reduced autofragmentation. Established C. globularis meadows can negatively affect tall-growing angiosperms such as M. spicatum when the environmental conditions, such as low phosphorus availability and high water-clarity, are appropriate. These findings have implications for the management of lakes, specifically those where a nuisance growth of tall macrophytes occurs, e.g. in systems where M. spicatum is invasive. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
