Assessing the Ecological Status of the Seekoeivlei Wetland, South Africa: a Nematode Community Case Study

The nematofauna of the Seekoeivlei Wetland in the north-eastern Free State province of South Africa was studied in order to determine its ecological status. Nematodes were collected in three different surveys, in October 2011, and in February and May 2012. Samples were taken from three sites within the reserve, each representing a different habitat. A total of 37 genera belonging to 21 nematode families were identified. The highest nematode diversity was observed during the summer sampling survey. All trophic groups were represented in only two sites in February. Maturity index was lowest in February (MI2-5 = 1.99) and highest in May (MI2-5 = 3.25). Non-metric multidimensional scaling analysis showed separation of seasons with winter and spring being most different from each other, which was supported by ANOSIM (R = 0.704; p < 0.001). The nematode faunal analysis profile of most of the soil food webs per locality per survey clustered into quadrat C, demonstrating that overall the Seekoeivlei Wetland was undisturbed with moderate enrichment and represented by fungal decomposition pathways. This study was the first to use nematode community data solely to determine the ecological status of a wetland in South Africa, which may henceforth be used for reference purposes.