Macrophyte presence and growth form influence macroinvertebrate community structure

Multivariate analysis demonstrated that macroinvertebrate assemblages of macrophyte-dominated sub-habitats within a small eutrophic pond differed markedly from those of Bottom substrate and Open water habitats. Certain habitats (e.g. Nymphaea and Phragmites) appeared to be quite similar in their macroinvertebrate communities, whereas others appeared to be very distinct in terms of the species composition (e.g. Open water habitat). Analysis of functional feeding groups also revealed differences between habitats in terms of the community structure. Again, the Open water habitat exhibiting the most marked difference. Macrophyte growth form does not cause significant differences in macroinvertebrate species richness and diversity but it has a significant effect on macroinvertebrate abundance. Habitats consisting of highly branched and dissected macrophyte growth forms provide more food resources and microhabitats supporting larger numbers of macroinvertebrates than macrophytes with firm undissected stalks and leaves. This study highlights the importance of maintaining the ecological quality of small freshwater habitats in order to promote macrophyte growth and thus maintain a high level of species richness within such ecosystems