Occurrence of non-mycorrhizal plant species in south Swedish rocky habitats is related to exchangeable soil phosphate
Article first published online: 16 SEP 2004
Journal of Ecology
Volume 92, Issue 5, pages 808–815, October 2004
How to Cite
OLSSON, P. A. and TYLER, G. (2004), Occurrence of non-mycorrhizal plant species in south Swedish rocky habitats is related to exchangeable soil phosphate. Journal of Ecology, 92: 808–815. doi: 10.1111/j.0022-0477.2004.00912.x
- Issue published online: 16 SEP 2004
- Article first published online: 16 SEP 2004
- Received 30 October 2003 revision accepted 26 April 2004; Handling Editor: Ian Sanders
- arbuscular mycorrhiza;
- plant coexistence;
- plant strategies;
- soil acidity;
- species richness;
- stress tolerance
- 1Plant species that do not typically form mycorrhiza are most likely to be successful under conditions where mycorrhizal fungi are not important for plant coexistence or where the costs of symbiosis outweigh the benefits. The relative occurrence of non-mycorrhizal species was investigated in relationship to exchangeable soil P in herbaceous vegetation, where arbuscular mycorrhizal (AM) associations are generally common. We investigated a total of 439 sites in rocky habitats with sparse vegetation and 110 meadows with dense vegetation.
- 2In both rocky habitats and meadows, soil pH was inversely related to exchangeable P. In rocky habitats plant species richness increased greatly between pH 3 and 5 and was also inversely related to P.
- 3Plant communities in rocky habitats contained a relatively larger proportion of non-mycorrhizal species than those in meadows. More non-mycorrhizal species occurred at high soil P in the rocky habitats, but no such relation was found in meadows.
- 4Non-mycorrhizal species in rocky habitats were most common at low soil pH (high P availability). Plant species that thrived at extreme soil pH were often non-mycorrhizal.
- 5The occurrence of fewer non-mycorrhizal plants in meadows than in rocky habitats supports the hypothesis that AM associations are more important in ecosystems with intense competition among plants. In rocky habitats, where abiotic stress may restrict photosynthesis more than nutrient limitation does, it is adaptive for plant species to utilize strategies other than mycorrhiza, particularly at low pH sites where P availability is likely to be adequate.