Dispersal and Dynamics of Planktonic Organisms in Hydrothermal Vent Plumes

深海热液喷口特有群落的发现引发了这样一个问题：这些物种如何能够在与世隔绝的短暂喷口生境中持续进化一段时间。一种可能性是，底栖无脊椎动物的幼体和早期幼体被卷进从喷口发出的漂浮热液羽流中，并被运送到位于海底数百米上方的侧向羽流中的偏远喷口栖息地。穆利诺博士及其同事将通过对热液羽流中幼虫的分布进行采样，并使用流体动力学模型来预测幼虫的扩散动力学，来检验这一假说。热液羽流还可能将还原的底物(如锰、铁、甲烷)、微生物和栖息在喷口的浮游动物向上输送到海底数百米以上的浮游生物群落。这些科学家将通过表征浮游动物的碳和氮同位素组成，以及检查其肠道中是否存在来自喷口的矿物沉淀物，来调查浮游动物是否同化了化学合成来源的资源。如果向水柱中注入化学合成的固定碳丰富了横向羽流水平上的食物资源，那么他们应该会找到浮游动物生物量上升和羽流中物种组成发生变化的证据。

The discovery of endemic communities at deep-sea hydrothermal vents has promoted the question of how these species are able to persist over evolutionary time in isolated, ephemeral vent habitats. One possibility is that larvae and early juveniles of benthic invertebrates are entrained into the buoyant hydrothermal plumes emanating from vents, and are transported to remote vent habitats in lateral plumes, several hundreds of meters above the seafloor. Dr. Mullineaux and associates will examine this hypothesis by sampling larval distributions in hydrothermal plumes and by using hydrodynamic models to predict larval dispersal dynamics. Hydrothermal plumes may also transport reduced substrates (e.g. manganese, iron, methane), microbes, and vent-dwelling zooplankton up into planktonic communities several hundred meters above the seafloor. These scientists will investigate whether zooplankton assimilate chemosynthetically-derived resources, by characterizing their carbon and nitrogen isotopic composition, and by examining their guts for presence of vent-derived mineral precipitates. If the injection of chemosynthetically-fixed carbon into the water column enriches the food resources at level of the lateral plume, then they should find evidence of elevated zooplankton biomass and altered species composition in the plume.