Trophic structure of free-living nematodes in the Saigon River, Vietnam

Abstract

Sub-tidal free-living nematodes in 12 stations along the Saigon River were investigated in both dry and rainy seasons during 2014 and 2015. In total, 157 nematode genera were found to belong to 59 families, and 11 orders of two classes of Enoplea and Chromadorea were identified. The trophic structure of free-living nematode communities was analysed spanning the overall seasons to see that deposit-feeders developed dominantly in the Saigon River indicating their association with food types including particles, bacteria, diatom, etc.. The dominance of deposit-feeders was contributed to a high abundance of genera in each station, including Theristus, Teschellingia, Monhystera, Thalassomonhystera, Paraplectonema, Daptonema, Aphanonchus, Sphaerotheristus, and Geomonhystera. Epistrate-feeder types were found as the second most abundant group. The remaining feeding types, such as chewers and suction-feeders, were in rather low proportion at most stations.