The distribution and controlling factors of meiofaunal community in Prydz Bay, Antarctica

Abstract

Meiofauna are important components of marine benthic communities. However, knowledge of meiofauna in Antarctica is limited, especially in East Antarctica. Samples of meiofauna from sixteen stations were collected in Prydz Bay and its neighboring area from February to March 2013, and could be divided into three regions by depth: Bay area (BA), continental Shelf area (SA), and Deep-sea area (DA). Up to twelve taxa were identified. Nematodes were the dominant taxon, accounting for 97% of the abundance. The average abundance of meiofauna were 1181 ± 1137 ind·10 cm−2 and decreased with increasing distance from coast, as did the number of meiofauna taxa. More than a half of meiofauna individuals occupied the upper 2 cm of sediments. Many individuals (41.5%) were 65–125 μm, but there were differences among the four dominant taxa. Cluster analysis at the taxon level showed that the sixteen stations could be separated into three clusters, which were nearly strongly associated with geographic location. Large differences in abundance were found in the three regions, and environmental factors such as food availability, grain size of surface sediments, and depth greatly shaped the distribution. It was unusual that abundance of meiofauna was significantly and positively correlated with depth in Prydz Bay, which was likely resulted from food supply, topography and circulation, as well as relatively suitable sediment size and reduced disturbance from icebergs.