Macroinvertebrate diversity within pan wetlands in relation to geological type and hydroperiod in a protected subtropical Austral national park

Abstract

Despite their small size, wetland pan systems play a crucial role as habitats for diverse aquatic biota. Macroinvertebrate diversity across 12 pan wetlands in relation to geological type (i.e. sandstone, granite, basalt and rhyolite) and hydroperiod (i.e. high, low) in a protected subtropical national park in South Africa was studied. Water temperature, pH, TDS, conductivity, phosphates and salinity showed significant differences among hydroperiods, with significant differences among geological types being observed for water temperature and ammonium. Most of the sediment variables were found to be significant across hydroperiods and geological types. 5145 macroinvertebrate individuals belonging to 41 genera and 9 orders were identified. Macroinvertebrates were diverse during the high hydroperiod and abundant during the low hydroperiod. The canonical correspondence analysis explained 35.8% of the fitted cumulative variation in the macroinvertebrate community structure and environmental variables across different hydroperiods and geological types. This study aimed to provide a better understanding of how they are influenced by a pan geological type and hydroperiod, and this information is crucial as it aids in providing management options for refuge aquatic taxa in a protected area and for the protection of these wetlands