Ice, Ice, Babies! The role of periodic and catastrophic ice loss on species connectivity in polar systems.

利用冰-海模式预测未来变暖情景下幼虫扩散的变化。Griffiths等人（2021）在距离开阔水域260公里的Filchner-Ronne冰架（FRIS）下的一块巨石上发现了海绵组合，标志着首次在冰架空腔内观察到硬基质固着生命。目前还无法对FRIS巨石上的生物进行物种水平的鉴定，我们也不知道这一组合的年龄或起源。我以前对这个主题的研究仅仅是基于确定FRIS下的海绵组合和威德尔海大陆架上的海绵种群之间是否存在连通性，以及埃克斯特龙大陆架上更远的海绵种群。这项研究是在开发了一个生物学上精确的海绵生命周期模型之后进行的，该模型包括浮游幼虫阶段和成虫无柄阶段--其他扩散模型出版物只关注幼虫阶段。这项研究的初始阶段将包括一个主题审查，重点是冷水和深海海绵的生殖动力学，以及威德尔海和FRIS区域内的基本海洋学条件。还将进一步完善现有的扩散模型，在模型中引入潮汐和更准确的海绵繁殖、生长和死亡时间尺度。威德尔海是一个不断变化的生态系统，其中季节性海冰变化直接影响FRIS下方和威德尔海大陆架上的海洋学条件。人为气候变化导致的冰盖变化将导致进一步的海洋变化，本项目将利用水动力扩散模型评估这种变化如何影响以下气候情景下的幼虫连接：i）海冰覆盖率低的季节ii）威德尔海中的Polynya存在iii）冰山崩解事件siv）冰架崩塌这些扩散模拟的结果可以在考虑威德尔海内无柄底栖种群的管理策略时使用，但除此之外，这一建模框架有可能应用于冷水珊瑚或冰鱼等其他生物的幼虫扩散建模。或者，改变建立模型所依据的海洋学数据意味着，操作域可能会转移到罗斯海或北极地区，以便在未来变暖情景下在这些地区进行建模应用。

Using ice-ocean models to predict changes in larval dispersal under future warming scenarios. The discovery of a sponge assemblage on a boulder beneath the Filchner-Ronne Ice Shelf (FRIS), 260km from open water, by Griffiths et al. (2021) marked the first ever observation of hard substrate sessile life within an ice shelf cavity. No species level identification for the organisms present on the FRIS boulder has been possible, nor do we know the age or origin of this assemblage. My previous research into this topic was solely based upon identifying whether connectivity existed between the sponge assemblage beneath the FRIS and those sponge populations present on the Weddell Sea continental shelf, and sponge populations further afield at the Eckström Shelf. This was carried out following the development of a biologically-accurate sponge life cycle model, which includes both the planktonic larval stage and the adult sessile stage - other dispersal modelling publications focus solely on the larval stage.The initial stages of this research will be composed of a subject review focused on reproductive dynamics of cold-water and deep-sea sponges, and the underlying oceanographic conditions within the Weddell Sea and FRIS region. Further refinement of the existing dispersal model will also occur, to introduce tides and more accurate reproduction, growth and mortality timescales for the sponges within the model. The Weddell Sea is a changing ecosystem in which seasonal sea ice variations directly impact oceanographic conditions both beneath the FRIS and on the Weddell Sea continental shelf. Changes in ice cover as a result of anthropogenic climate change will lead to further oceanographic variation, and this project will utilise a hydrodynamic dispersal model to assess how this variation will impact larval connectivity under the following climatic scenarios:i) Seasons of low sea ice coverii) Polynya presence in the Weddell Seaiii) Iceberg calving eventsiv) Ice shelf collapse The results of these dispersal simulations may be utilised when considering management strategies for sessile, benthic populations within the Weddell Sea however in addition to this, this modelling framework has potential applications for larval dispersal modelling for other organisms such as cold-water corals or icefish. Alternatively, changing the oceanographic data on which the model is built means that the operating domain may be transferred to the Ross Sea or areas within the Arctic, for modelling applications in those regions under future warming scenarios.