Abundance of Bitectatodinium spongium in surface sediments

We present an emended diagnosis of Bitectatodinium spongium (Zonneveld, 1997) Zonneveld et Jurkschat, comb. nov. previously described as ?Algidasphaeridium spongium. New data from surface samples of the Pakistan shelf are combined with information from sediment traps off Somalia and Arabian Sea surface sediments to elucidate the taxonomy, ecological affinity and preservation of B. spongium. A pronounced relationship is detected between high concentrations of B. spongium and well-mixed, nutrient-rich surface waters, as observed in upwelling regions and in the vicinity of the Indus River outlet. High concentrations of this species are also found in coastal regions and regions with tropical sea surface temperature conditions. No relationship is observed between its distribution and differences in sea-surface salinity nor evidence for decay of B. spongium in relation to oxygen availability in bottom sediments.

我们针对原被暂定为？Algidasphaeridium spongium的Bitectatodinium spongium（Zonneveld, 1997）Zonneveld et Jurkschat新组合（comb. nov.）作出修订后的分类鉴定。本研究整合了巴基斯坦陆架表层沉积物样品的全新数据，以及索马里近海沉积物捕获器与阿拉伯海表层沉积物的相关资料，用以阐明B. spongium的分类学特征、生态亲和性与保存特性。研究发现，B. spongium的高丰度与充分混合的富营养表层水体存在显著关联，该现象在上升流区及印度河入海口附近均有观测到。该物种的高丰度同样见于沿海区域与具有热带海表温度特征的海域。本研究未观测到其分布与海表盐度差异存在关联，也未发现B. spongium的降解过程与底沉积物中氧气可获得性相关的证据。