Competitive abilities and related strategies in four aquatic plant species from an intermediately disturbed habitat

• Published in: Freshwater Biology
• Main Authors: Greulich, S., Bornette, G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1999
• Subjects: Rhone; Groenlandia
• Online Access: http://dx.doi.org/10.1046/j.1365-2427.1999.00395.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2427.1999.00395.x; https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2427.1999.00395.x

Summary 1. High species richness in disturbed habitats is commonly attributed to the coexistence of species with diverse competitive abilities and, more generally, to the coexistence of different plant strategies sensu Grime (1977, 1979). The present study tests this assumption for the case of intermediately disturbed, species‐rich macrophyte habitats. 2. Four species, Sparganium emersum , Hippuris vulgaris , Groenlandia densa and Luronium natans that coexist solely in one flood‐disturbed, cut‐off channel of the Upper Rhone River (France) were selected for this study. Apart from this common, disturbed habitat, they presented different distribution patterns within the floodplain. The present study aimed to establish both a hierarchical ranking of their competitive abilities and their respective strategies according to the C‐S‐R‐model. 3. The study was carried out during one growth season in a de Wit experimental design with supplementary monitoring of growth characteristics. Whereas a clear ranking of species competitiveness could not be established, the experiment revealed differences in their traits and strategies. 4. S. emersum possesses the traits of a competitor, whereas the other species present intermediate secondary strategies, with a C‐R‐strategy in G. densa , a C‐S‐strategy in H. vulgaris , and a C‐S‐R or S‐R‐strategy in L. natans . These strategies are well matched to the distribution of the species within the floodplain, since the distribution of S. emersum reaches far into weakly disturbed and undisturbed, and supposedly competition intensive sites, whereas Luronium occupies a habitat that is both disturbed and relatively nutrient‐poor. Only the presence of Hippuris in disturbed habitats seems not to correspond to the established strategy, but this might be explained by its need for only moderately intensive competition and by particularities of its regeneration strategy. The revealed differences in strategy may also make it possible to interpret the patchy pattern in vegetation cover within ...