The influence of biotope and sampling method on the assessment of the invertebrate community structure in endorheic reed pans in South Africa

Abstract

Reed pans in the Mpumalanga Lakes District, South Africa, support an abundant diversity and richness of aquatic macroinvertebrates in a variety of different biotopes which, in the case of depressional wetlands such as reed pans, are not well studied. This study was undertaken from 2008 to 2009 and focused on determining the diversity and richness of aquatic macroinvertebrates supported by various biotopes, as well as identifying a sampling method which is able to retrieve a representative sample of macroinvertebrates from reed pans. Aquatic macroinvertebrates were collected using an aquatic light trap, benthic grab sampler, emergence trap, plankton net, sweep net and terrestrial light trap. Marginal and emergent vegetation were found to have the highest diversity and richness of aquatic macroinvertebrates. A sweep net proved to be the most efficient method for sampling aquatic macroinvertebrate communities in reed pans. By sampling marginal and emergent vegetation with a sweep net, variability between sites and seasons was minimised.

Keywords: biomonitoring, biotopes, diversity, Mpumalanga, richness, sweep net, wetlands

African Journal of Aquatic Science 2011, 36(1): 67–74